Why wind power works in Denmark
Posted by Super G on August 31, 2006 - 7:40pm
[editor's note, by Super G] The following is a guest post from Cry Wolf.
This post is based on an excellent report titled "Why Wind Power Works in Denmark" by Hugh Sharman, which can be found here.
The main problem with most oceanic and climatic forms of renewable energy—wind, tidal, wave and ocean currents—is that electricity generation is sporadic and may not be linked to the times that power is needed. Hydroelectric power alone provides a means of storing this oceanic/climatic renewable energy for use when it is most needed making Hydro an invaluable source of electricity.
The current absence of a means of storing wind energy leaves electricity grids at the mercy of the weather and critics have long since pointed out that wind energy cannot provide a grid base-load. Furthermore, it cannot be relied upon to provide peak electricity production. So what is the point in having wind energy? It has seemed to me that wind's primary purpose has been to provide politicians with a feel good factor and grounds for claiming green credentials.
Sharman reports wind energy production data for Denmark for the whole of 2003 and shows how shockingly unreliable wind energy production is. But he also shows how the Danes and their Scandinavian neighbours have made wind energy work productively by balancing Danish wind energy output against Norwegian and Swedish Hydro generation and here in lies the main message of this post. But first, a summary of the findings.
Denmark
Denmark lies on the eastern margin of the North Sea where it is quite windy. The population is around 5.5 million and the country produces the highest per capita amount of wind energy in the World. There is 0.88kW installed wind capacity per capita in Denmark compared with 0.18 kW per capita in Germany and 0.01 kW per capita in the UK. Wind supplies 16% of Denmark's electricity.
The Danish wind carpet
Denmark has 5500 wind turbines including two large off-shore wind farms. A total capacity of 2374 MW was installed by the end of 2003. The Danish grid is split in two (there are some large islands) and Sharman's report deals only with the west Danish grid, representing 80% of the total. Crucially, the west Danish grid was already connected to Norwegian, Swedish and German grids before the wind carpet was built.
A fine day at Horns Rev, the World's largest offshore wind farm
Load factor
The load factor of the Danish wind carpet is only 20%. In other words, for every 5 MW of installed capacity the wind carpet on average produced 1 MW during 2003. Information on the cost of installing wind power is given here.
On average 1kW of installed wind power costs $1000. Therefore, to get 1 MW return, 5 MW costing $5million needs to be installed.
Highly variable output
There were 9 occasions in 2003 when the wind carpet produced at > 2000 MW (>85% of installed capacity) but these periods of high output were short lived (Sharman, Figure 8). The output suffers from extreme high amplitude high frequency variance - in other words it is very spiky. "Sometimes the Danish wind carpet produces maximum output when there is little demand. On other occasions it delivers no energy when demand is high". On one day during 2003, the wind carpet actually consumed more energy than it produced.
I find the high variance in output surprising as I'd always assumed that wind in one location would compensate for no wind at another and this should result in some smoothing of output. In Denmark it seems that the wind blows everywhere at once and this may be due to the flat topography and relatively small area. In larger, topographically more variable countries it might be expected that greater smoothing of output will occur.
How the Danish grid is balanced
The west Danish grid is connected to the Norwegian, Swedish and German grids. The inter connectors were built as export lines of Norwegian and Swedish hydroelectric power to Germany but have found a new use in helping to balance the highly variable wind output from Denmark.
Figure 13 (Sharman) shows the hourly output from the Danish wind carpet in December compared with energy exchange over the interconnectors. This shows quite amazingly that essentially all Danish wind power is exported to Norway and Sweden. These countries dynamically balance the interconnected grid using their extensive hydroelectric generating capacity that can be adjusted rapidly to compensate for the highly variable input from Danish wind. In essence, water is conserved in Norway and Sweden when the wind blows in Denmark. This conserved water can be used to produce power when it is needed. This to my mind is a brilliant scheme that essentially provides a means of storing wind power through conserving hydro power.
Energy sinks
Sharman also points out that some of the variance in Danish wind energy output gets sunk into the massive German grid that lies to the South. The variance in the Danish wind supply is only a problem for Denmark because wind energy represents a significant proportion of the total grid supply—16%. Any country wanting to rival the Danish wind model will have to either develop a grid balancing system or develop energy sinks within the grid or both.
A few weeks back some TOD engineers were throwing around ideas about using the batteries of electric cars as sinks for wind energy. This sounded a great idea. Would it also be possible to develop water-heating systems in public buildings to store heat when the wind blows? Would it be possible to use wind energy to actually pump water back into hydro dams using existing pump storage schemes?
Conclusion
Denmark has no indigenous hydroelectric power but has managed to negotiate a power balancing agreement with Scandinavian cousins to make their wind carpet work. Larger countries such as the US and the UK that have extensive hydroelectric capacity must surely manage to engineer a power balancing act between their wind and hydro generators.
Cry Wolf
AKA Euan Mearns
euan dot mearns at btinternet dot com
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The concept is called Vehicle to Grid or V2G and several summeries on the concept can be found here:
http://www.udel.edu/V2G/
http://www.vehicletogrid.com/
Also there is a promising Australian invention - Vanadium batteries. However in the usual nature of Australian innovation it is completely ignored here until the inventor finally moves offshore where it is enthusiastically embraced and marketed.
http://tyler.blogware.com/blog/_archives/2006/8/30/2280046.html#comments
http://www.vrbpower.com/
But I don't actually see how it helps at all as a wind sink. You need to charge your car to go to work tomorrow, whether the wind is blowing or not.
Might conceivably be useful for a set of spare batteries?
You'll be charging all night, probably plug back in once you get to work.. so for a great majority of the day, your PHEV's batteries will be working with the system. Be interesting to see if the 'Park and Ride' concept would grow to include plug-in's at the train station parking spaces instead of parking meters, and your net electricity usage is charged or credited accordingly.. Could the parked cars (and electric bikes/mopeds) actually be helping to power the train that takes you on the next step?
If the system was modular, there would be the potential for some truly massive battery systems to be connected together. During non-workday hours, there would be a complementary need to recharge many of them, allowing for a lot of 'sponging', and also a balancing of the disproportionately high daytime demand.
e.g. 50% more than I actually need for my daily commute.
... so if there's a windy night, my battery gets a full charge. And if there's a week without wind, my battery only charges to 50% every night. And I need an override button to charge it to 100% (at a higher price), because I've got a longer trip tomorrow.
Something like that.
This would smooth out demand during the 12 or so hours at night that the car was available for charging, as well as eventually during the day at work, when charging stations were installed in parking garages and at meters, like in Minnesota and Canada for engine heaters.
As battery size grows, the period of time for which the battery can provide smoothing would grow from the daily cycle, to a weekly cycle and more.
Thxs for this post. It has many good ideas. My suggestion is that wind power could also be harnessed to pump seawater behind seaside dams built along the mountainous seashore. Not sure of the environmental effects, but it might be a good way to store energy in areas where there is insufficient freshwater runoff to justify a hydrodam.
Bob Shaw in Phx,Az Are Humans Smarter than Yeast?
However, tide power is intermittent, though predictable... so the pumped-storage aspect would need to be big enough to mask the tidal variation, otherwise you're creating another imbalance problem.
Paradoxical.
The integration of wind power is high on the agenda in Europe. Here you can find the Wind energy industry views. They indicate that in the European grid some 20 % wind can be integrated "without problems" in the EU. Industry wiewpoints, but better than speculation.
http://www.ewea.org/index.php?id=60&no_cache=1&tx_ttnews[tt_news]=43&tx_ttnews[backPid]=1&cHash=f7f7678089
At the bottom links to the main reports
http://www.ewea.org/fileadmin/ewea_documents/documents/publications/grid/051215_Grid_report.pdf
A lot of talk- but also useful technical info.
Regards And1 from Denmark :-)
http://www.dom.com/about/stations/hydro/bath.jsp
Pumped air is limited to ~60% efficiency due to adiabatic heating/coolling.
Wind & hydro are a VERY good match. Hydro can be dam (run-of-river not so good) or pumped storage (ideal).
New Zealand can accept "at least" 35% wind energy because they are half hydro. Once they get close to 35%, they will study the issue more.
An interesting note. Hydro is twice as variable as wind on an annual basis (per speaker at HydroVision). "Wind droughts" are rare.
Except in the form of reduced water consumption in the dams, of course.
New Zealand can accept "at least" 35% wind energy because they are half hydro. Once they get close to 35%, they will study the issue more.
Does that mean that with a wind-hydro balancing system that you can install up to 70% of your hydro capacity as wind?
Note your point about droughts - its just that here in Scotland we've never had any direct experience of drought. Though in Norway, lesser snow falls in recent winters have left many magazines half empty - skiing across those in winter can be interesting with massive tangles of ice blocks along the shores.
Sounds plausible to me. You would also need good transmission linking the whole system.
Regards,
Thomas O. Gray
American Wind Energy Association
www.awea.org
www.ifnotwind.org
Regards,
Thomas O. Gray
American Wind Energy Association
www.awea.org
www.ifnotwind.org
Recently a TOD poster suggested that we need to move from nature's stocks (fossil fuels and uranium) to nature's flows (wind, solar, geothermal).
The challenge is that the current business model of the investor-owned, coop and muni utlities doesn't necessarily lend itself well to a free market. The non-generating utilities (generally smaller munis and coops) need to recover their T&D costs. The large investor owned utilities have an inherent bias towards large, centralized plants and feel threatened by distributed small hydro, wind and other DG technologies so charge high interconnect fees, pay avoided costs rather than time-of-day, market rate pricing and increase the hassle factor for small and medium sized self-generators and independent power producers.
The requirement for ISOs (Independent System Operators) where transmission and distribution is decoupled from generation has been helpful in some markets though the big players are still quite effective in most places in limiting competition.
At this point a market restructuring is needed but the rolling black-outs and sharp price hikes in California has arrested interest in market reform (despite the subsequent disclosures on how much that the disarray was market manipulation by Enron and others).
On a seperate but related note in July 2006 the US DOE and EPA released a comprehensive report "National Action Plan for Energy Efficiency" (see http://www.epa.gov/cleanenergy/actionplan/eeactionplan.htm) that highlights the challenges of utilities planning for and investing in energy efficiency as an alternative to building additional capacity.
http://www.aip.org/tip/INPHFA/vol-9/iss-5/p8.html
Interconnects might be risks from the standpoint of cascading blackouts ... but that looks like a big system in place already for north american electricity trading.
Odd article. The claim is that the grid needs to be managed as a 'single machine".
The Center for Smart Energy (http://www.centerforsmartenergy.com) has several research reports which suggest that the difficulty with the grid is that it is still primarily electro-mechanical in nature which makes it quite difficult to manage. Power plants, substations, transfomers, and other physical components of the "system" lack the industry standard communication, command and control protocols that would make it much simpler and cost-effective to manage a distributed, heterogenous network rather than the "physical grid" the author emphasizes. The US DOE (particularly the Pacific Northwest National Lab) and others are defining what a 21st Smart Grid might look like.
This is not to say that there may be physical constraints and challenges in the T&D grid. It is to suggest that the grid is not a network without standard protocols, sensors, and digital controls that can more effectively manage and map system resources and improve siting and system expansion decisions. Such a Smart Grid would make it easier to monitor and manage a wide range of centralized and decentralized generating assets without requiring a single entity to control generation, T&D and billing to end-users i.e. it would effectively allow the movement from monopoly to market by decoupling generating, transporting and billing for electrons.
What significant maintainance and upgrade work is being done in the north east USA and what major new gridlines are in the pipeline to be built after the 2003 breakdown? Your breakdown were worse then ours and it should have resulted in emergency investments and not the slow ones to be completed 6-9 years after the need became apparant done here.
They are. In those jurisdictions where the networks are privately held note the use of 'eminent domain' to secure rights of way, as well as extensive regulation.
The daily deals are brokered on:
http://www.nordpool.com/
The benefit for hydro power is that you get paid better for day power during weekdays then night power wich means that you close the gates during nighttime and run full power during daytime.
I do not know about the Norwegian hydro power but most hydro power in Sweden were originally state owned, municipiality owned and corporate owned with origin from the pre electrical power use of the water falls. Unfortunately a generation of not so bright economists and CEO:s decided that powerplants were not core business and manny heavy industry corporations and municipialities sold hydro powerplants and shares in nuclear powerplants. In hindsight they sold them very cheap. They buyers were in the end mostly Finlands Fortum and the German E-On and the Swedish state owned Vattenfall.
There is now a cooperation of heavy industries where manny of them sold their powrplants who now are pooling resources to import electricity and build new powerplants they own.
Some is owned by local municipalities and counties, some by the heavy industries (smelters) and the rest by the state-owned power producer Statkraft.
There has been some debate during the recent years over ownership structure:
Many people are accusing Statkraft of Enron-like market manipulations. Statkraft hasn't shut down power plants for maintainance at the worst possible moments, but they have sold off power in the summer such that they cause prices to spike in the winter. The fact that they control something like half the Norwegian electricity production through it's subsidiaries and ownerships in community owned power producers, is viewed as negative for the power market. In 2005 the government ordered it to shed one of its subsidiaries; Trondheim Energiverk. Of course, during the summer of 2005 it became clear that Statkraft was receiving heavy bids from european power companies for this polished gem, which they had acquired on the cheap from the city of Trondheim during the 90s when many communities preferred to invest in the stock market or pay back bonds. The fear that some foreign company like E-ON or Vattenfall should have the highest bid instead of the county-owned Norwegian NTE, caused the new leftwing government to shortstop the deal in the autumn of 2005.
In Norway we also have a special law that says ownership of a hydro-power plant will revert to the state after 100 years. As many power plants are approaching this age, there have been complaints of lack of investment in old power plants.
One company which owns many of these plants, Norsk Hydro, is also the second largest power producer of Norway. Hydro may be a public company, but it's owned 43.8% by the Norwegian state.
As mentioned above, many local communities chose, during the 90s, to sell their stocks in power companies, mainly to Statkraft. Those communities that chose to put their money in the stock markets instead, are trying to put up a brave face as power companies are now raking in profits.
The balancing of wind with hydro is a bit complicated. Since the power bourse (Nordpool) only accepts bids a day in advance, I guess the wind power plants just have to dump their power on the grid and let the grid system operator deal with it. Of course, if a company owns both hydro and wind, they can sell power equal to their wind capacity and crank up their hydro power to replace the wind power that fails to materialize. Special deals between hydro and wind producers could serve the same purpose.
For more information on the Norwegian/Nordic electricity market, the norwegian system operator has more.
As an aside note - use of electric clothers dryers is not allowed in Switzerland during the day.
As I recall, the Swiss generally have drying rooms in the basements of apartment buildings. So a night-only system is pretty easy to set up, and can monitored by vigilant citizens... Even in individual houses, the Swiss are disciplined enough to respect such a restriction.
Hard to imagine it working in any other country, without financial incentives.
Also noted that at an average of 20% of maximum output, you need $1000 worth of installed capacity to produce an average of 200W of power ($1000 per kW of max. capacity). Even without cost allowance for maintainance, this works out at $5 billion per GW - about the size of a large "conventional" coal-fired station. Even though you don't need any fuel thereafter, it makes it look unattractive as long as there is coal to be burnt which is at a reasonable price.
Those also serve who only stand and wait as Milton said.
There is an hierarchy of reserves depending on how fast they can come on line. Steam turbines take the longest to start up from cold, gas turbines are faster and for the fastest response from conventional plant some of the reserve is keep with the turbines turning but not generation power , the `spinning reserve'. This is the most expensive as it consumes some fuel. Dinorwig's outstanding characteristic is that it can go from 0 to 1300MW in 15 seconds from cold. It earns a steady profit standing ready to do this around the clock but only on a few occasions actually doing so.
In the US capacity factor is about 30%.
phil said,
" energy loss problem, think it's something like 5% per 1,000 kilometres, not insubstantial. Maybe this is something that will improve with time though?"
It is already improving and is one of the giant "quite revolutions" underway in the energy industry. The trick is to and power in distrubuted, decentralized, and diversified ways throughout the grid, and make the grid a "live smart grid" instead of "dumb terminal" type grid, as it has historically been. this is the goal of DG or Distributed Generation, sometimes called distributed energy:
www.distributedenergy.com/de.html
By having a network of semil self supporting but still grid connected power generators of all sized mixed into a "smart grid" and networks of "mini-grids" then a variety of power production types (natural gas generators, propane generators, waste gas to methane powered generators, Diesel generators, wind generators, solar and photovoltaic generators, mini-hydropower units, on and on, can be mixed in various sized into the grid making it "super flexible" and diversified in the types of power coming in and the variety of sources they are coming from. This would mean that no kilowatt in particular would have to travel very far before finding it's customer, and the further along the path, the variety of distributed generators would put the power on the grid to service the customers at greater distance. The larger centralized power stations would still be there to do the "baseline" support, and peaking activity, but as more and more distributed unites handle their own peak, the peak loads could come down considerable, to the point that at some future time, the day/night and month to month line would be almost flat with very small "bumps" instead of "peaks".
The other shoe to fall is electric storage. Batteries are improving but still expensive...CAES (Compressed Air Energy Storage) is viable but again, not cheap...flywheel systems may make their breakthrough here, as may fuel cells (both much, much better in a stationary setting than in transportation, where I don't think they will ever find a market, despite the high hopes of the auto fuel cell and flywhell proponents, they have been tried for 30 years in transport and still not delivered).
Some have mentioned the "pumped hydro option:
This is not cheap, but has the advantage of providing water catching areas for irrigation, recreational and nature enhancing lakes, and provisioning drinking water for populations, not a bad trade when you add in the energy storage function as well. Pumped hydro can be integrated to wind as well as using off peak electric grid power to pump the water up, and even further enhance the efficiency.
http://www.electricitystorage.org/tech/technologies_technologies_pumpedhydro.htm
http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity
http://www.publications.parliament.uk/pa/ld200304/ldselect/ldsctech/126/12624.htm
however, if we want to build many of them, we need to do so "pre peak". The cost of fossil fuel (Diesel for machines) in construction is already higher than it would have been a few years ago, and the cost of concrete construction due to the natural gas cost, while off the post Katrina peak, is still considerably higher than it would have been a few years ago.
I and some associates once looked at the possibilty of putting 12 to 16 medium sized pumped storage sites down the Ohio River Valley, From Pennsylvania to just above St. Louis MO/Cairo IL, which would have flattened the day to night peak for a fair market area in PA, IL, OH, IN, KY and reduced greenhouse gas emission over years by Billions of tons, plus provided wetlands for wildlife, waterfowl and fish, and irrigation drinking water reserve. But flattening the day night peak would have been the jewel in the crown.
Of course, this is coal country. Do you think anyone would invest in saving a few million tons of coal, as givaway cheap as it has always been. :-(
As Bertold Brecht said, "Such is life."
Folks, I tell you again, the technical problems are NOT the problems.
Roger Conner known to you as ThatsItImout
The Swedish grid were mostly built to transfer cheap hydro power from north to south, interconnect large powerplants, provide for power trading with our neighbours and then there are additional links for redundancy. The main incentive for new investments is to keep the margins large enough for the power trading and increase the redundancy.
The new thing as I see it is small generation units becomming economical to run and better smarts to disconnect parts of or subdivide a grid if there are major faults in it.
Pump storage hydro schemes will surely be expensive, but if this infrastructure already exists, I just wonder if their use could be modified to store wind energy - to at least smooth out some of the short time scale fluctuations.
In the UK, the renewables debate normally revolves around reducing CO2 production. No one is thinking about the possibility that there may not be enough gas to fire the power stations by 2020. At some point national governments will need to exert more influence over the generating and transmission infrastructure companies to ensure that the non-technical problems to which you refer are overcome.
I've been thinking about a storage mechanism which is essentially scalable, but probably not logistically (or ferrously) feasible. But it's dead-simple, probably durable, and the essential components (height and mass) are in ready supply.. so, Instead of pumping liquids up to a height, I was wondering about the efficiency of simply raising and dropping dead weights. Lots of them, of course. After the build, the economics would hang principally on the efficiency of electric motors for lifting, and the subsequent efficiency of generators for recapturing it in descent. But unlike batts or hydrogen, there's no 'leaking or self-discharge'.. gravity is a constant.. and unlike hydro, you avoid the costly friction, adhesion and turbulence losses found with fluid dynamics.
Could be a good use finally for all those heavy SUV's..
Of course, you've got to use a bunch of steel, maybe a track system, or a convenient cliff-site to access as much drop as you can. Choose whether cables or chains, etc..
Simple thought from basic physics.. but everything has the potential to look ugly when blown up to a global, industrial scale.. even the Stay-Puf marshmallow man.
Bob Fiske
You meant 'amusements', right? I think Letterman would do it.
Actually, I think this has a much lower engineering challenge than flywheels, which need extremely exacting bearings, balancing and I guess often vacuum enclosures, to prevent airflow-induced losses. The investment is high, maintenance by specialists, catastrophic failure always possible. Lofting heavy weights with cables up steep or vertical rails, on cables or chains is far simpler. There is a fraction of the amount of movement involved, hence engineering, friction losses, calibrations, wear.. A total failure is a straight drop, not an explosion, so burying it is not necessary, just maybe a warning bell for the picnickers below.. even so, it's easy to implement locks to catch breakaways..
Please do the design and the math, you will have surprises...
A total failure is a straight drop, not an explosion,
Which releases EXACTLY THE TOTAL STORED ENERGY just like the flywheels, a man made earthquake, have to compute that too.
I'm happy to hear your thoughts on how flywheels might have an advantage, and they certainly might.. but as far as the aspects that I mentioned, the potential energy of simply holding mass up against gravity is both a technically simple and an extremely flexible and scalable means of storing energy. Needs a good amount structural materials, cables and motor/generators. And a bunch of sand, or etc.
There are numerous ways to mitigate the forces in case of system failure. Surely, the same amount of force is expelled if the weight manages to fall the full distance, assuming the cables and braking systems all failed, but it could impact a pool of water and divert most of that energy into spray, for example.. the system could (should) consist of multiple, independent weight-runs, so the failure of one of them produces a limited 'thud' and not a catastrophe, and full shutdown. (Of course the same paralleling is available to either technology)
It just seems to me that the running costs of an essentially static, Low-Tech system has some inherent advantages over a complex one that relies on constant, high-speed rotation, where a serious failure might additionally render much of the system unusable, and where skilled maintenance and specialized part-replacements would detract from your overall yield. I like flywheels.. but I like simplifying problems, too. What do you see as the weak links in 'Project Sisyfus'??
Bob Fiske
If you try to handle the whole mass as a single chunk the "unit constraints" are not likely to be manageable.
If you split the mass into manageable pieces you get into a MESS of "structural materials, cables and motor/generators", costly and unreliable, need to shape up each individual chunks etc...
Try a very large hydraulic jack may be, and DO THE MATH!
I am not going to do that for you. :-)
I keep picturing the "catastrophic failure" of Zorba's "log transporting device" in the movie "Zorba the Greek". If you could make it that funny, it would be worth it! :-)
Roger Conner known to you as ThatsItImout
OK. I forgot the Irish. The Irish are pretty frickin funny.
http://www.consumersenergy.com/content/hiermenugrid.aspx?id=31
This seems to me to be the perfect companion to solar/wind power. Too bad we haven't built more of them.
Bokken
In Scotland, the wind blows in the north and the population lives in the south - so I'm keen to know how much of the 20% load factor actually makes it to market. Transmission distance from wind farm to city is around 300km.
European wind power tends to run at low capacity factors, because their electricity is more expensive and they have less domestic energy, so they are willing to exploit lower quality wind sites.
In the US capacity factor is about 30%.
If the wind sites in Scotland are high quality, you could get 30%+.
It seems to me that if alternate energy sources are connected to an extensive grid system, along with ways of storing unused power in times of low need--heat sinks, storage as future kinetic energy, etc--the future of such energy sources is brighter than the critics complain.
It might also be possible to store energy at the local level, aside from batteries. Kinetic energy can be stored using pulleys and weights, to be released in time of need. The initial cost may be high, but the benefits are easily recouped over time.
We keep thinking in terms of large projects; what is needed is the actual large connecting grid so that one person's excess compensates for another person's lack. That grid will encompass enormous areas.
I can imagine a system whereby energy is produced not only at the local, individual level--solar, small windmills, small hydro (one tiny waterfall in Canada powers a gigantic paper mill--as well as larger scale projects.
Critics attack each alternative energy source for its failure to supply total needs--the oil/coal paradign. We need to think of a far more complicated paradign based on a wide variety of inputs.
weather covers large areas. These are not independent variables. if your windmill isn't working, then chances are, neither is your neighbors, so connecting to him won't help.
That's at the household scale, which is tough. Institutional use of such technology should be much easier.
Consider how bad the vast majority of people are with remote controls / such ...
But, the idea of having as much distributed storage (plus generation ... other issue) with people being able to bid in the price they are willing to buy to store makes a tremendous amount of sense.
Home storage could include:
- Increased ice sections of all new refrigerators that freeze ice when power is cheap to then cool when power is expensive
- Ice units for air conditioners to do the same thing (this is already happening commercially with larger units http://www.happynews.com/news/8122006/some-in-calif-seek-ice-to-ease-crunch.htm) and will be coming for residential untis)
- Heat sinks for storing heating power in the winter (associated with heat pumps in reverse of the air conditioning requirement??? -- thus a combo icing unit for summer and boiling water for winter???)
- Plug-in hybrids with some storage capacity
- If affordable to develop, stored power through small water pumping (attic storage unit???), fly wheel, air pressure
- Current technology is battery storage (which, for example, GridPoint looks like the current best 'ready-made' power management/storage system out there ... www.gridpoint.com)
Some thoughts.This is probaby where this thing is goine. It would require government intervention to straighten out the internet connections, gas, water, and electrical connections though.
They'd have to make your electric and gas meters, and internet edge router all effectively the same gizmo, not something these companies would be clamoring for, but a huge win for efficiency if it was done.
Eventually, but will take a lot of sorting out first.
A few years back many of us were watching US natural gas storage with interest, where natural gas is stored in salt caverns, aquifers and depleted wells in the summer for winter need. Is it possible to have large scale hydrogen storage in such underground structures for load balancing for wind or solar electricity generation? Or is the hydrogen molecule smaller then methane to the point where it leaks out? It seems like we could have a number of depleted wells in the future to store hydrogen for load balancing.
Thanks in advance.
and
http://tonto.eia.doe.gov/oog/info/ngs/ngs.html
is the kind of thing I am thinking about
http://www.ihec2005.org/abstract/ORALPDF/AN%20INVESTIGATION%20INTO%20LARGE.pdf
http://www.praxair.com/praxair.nsf/AllContent/977AD7AAF855A6248525715A00718205?OpenDocument
I am not sure about the time response such a system would have compared to the variation in wind, but perhaps the daily variation in sunlight that solar collectors in the desert might get?
I'd also like to see a more reassuring explanation of vehicle-to-grid. Suppose for example if all the PHEV commuters are having breakfast and a power station on the grid goes down. Does that mean the batteries are 'sucked dry' just as they are about to leave for work? Perhaps a demonstration project is needed using an all electric car suburb.
If the vehicles are PHEV's and not EV's, it's a complete non-event: some drivers have their engines come on when they'd normally not run them at all, and some others have their engines come on a bit sooner.
A large and well-integrated fleet of PHEV's could smooth over load shocks which would otherwise cause huge blackouts (200 million vehicles * 5 kWh/vehicle = 1 billion kWH, or enough storage to absorb - or supply - the full nameplate power of every generator on the US grid for an hour.) Talk about turning things into non-events!
The first stage of PHEV/EV support for wind is demand management: charging more when wind is available (G2V). The second stage is V2G, where the vehicle sends power to the grid.
You don't use that carbon when you don't use the backup. Only a bit, if you need to keep it "spinning".
Same is true for the "off peak" power that the PHEV promoters say we can charge them with. Yes, that can fit into the existing grid, but it means burning more coal and gas in the power stations than is done now when the electric demand drops at night. That's hardly emissions-free.
But, PHEVs should not be the only storage devices. IMHO, there are NO silver bullets ... even if I think PHEVs (actually, I am more ready for plug-in, hybrid turbo bio diesel vehichles) have the potential to revolutionize the US (and global) energy situation.
I could be wrong about that though, I have noticed my local district heating system keeps gas boilers for peak loads rather than trying cut the peaks with hot water reservoirs. But it may be that they just haven't been invented on a grand scale yet.
I would work it so that you would sign your car up to a V2G utility company that sells spinning reserve, peak power or contracts to do grid stabilisation. When you sign up you would designate the most that can be extracted from your battery and how many times per week it could be done. You would have a SIMM card and an account much like a mobile phone. When you plug your car in it would log onto the network like a mobile phone and the utility would know exactly how many cars are online.
In this way your battery would not be drawn beyond what is needed for your daily commute. At the end of each month the utility would pay you for the power drawn from your battery at "spinning reserve" rates which are double the normal tariffs.
The V2G utility company would, in half hour intervals, poll the cars it has signed up and logged in and then communicate to the grid what will be available for the next half hour to avoid overcomitting its available resources.
I also see various V2G companies competing for your car as well. They would offer varying plans to get you to sign up with them rather than the competition. I guess you could also sign up to radical plans if your car is parked most of the time or mild plans where your car is used often. The radical plans could make the most money however shorten battery life and the mild plans would prolong battery life and range however make less money. It would all be up to you.
The generating and marketing were forcibly separated when the market was deregulated. Kenny Boy Lay was whispering in George Bush's ear when he was governor of Texas., and Enron was big in wind generation and deregulated electricity. But, sometimes people do good incidentally. The marketers are forced to buy from ERCOT who opperates the grid and they can't discriminate.
Green Mountain Energy sells electric accounts to individuals and companies partially generated fro wind at a premium. So do most of the Utilities. Its a great sign, people are willing to pay to be green even here in Texas! By the way, both ERCOT and Green Mountain have wesites. You can seee price comparison data at www.powertochoose. TXU is the biggest utility in Texas, and also has the most wind farms, but tax shelter promoters are building them too.
As far as salt dome cavities for hydrogen storage, it ought to work. And most salt domes are on the coast, near the petrochemical refineries which use a lot of hydrogen in cracking in refineries. They mostly use natural gas, and manufacture hydrogen from methane onsite. So the hydrogen has a nearby place to sell the gas. Since this is the process they use to refine heavy oil, and also use it to take the sulfur out of crude and gas, the market for hydrogen can only increase.
I've often wondered why we couldn't use the intermittent flow spikes to do other useful work, like desalinizatin. With tanks and dams the water can be stored, or pumped into aquifers. And West Texas sits on an ocean of salt water
I can't figure it out either unless they consider direct mechanical connection from the turbine shaft to the pump.
I don't think that's going to work. Practical wind turbines do sophisticated management of load and forces via electrical feedback.
It's much more practical to transmit the energy as electricity, I think.
2.You can do it using those dinky little windmills, but their efficiency is low and the vacuum desalinators you would use cost too much and have to be overbuilt, like the dinky little windmills, and are noisy, like the dinky little windmills.
3. You have to dump the salt brine left over from the desalination plant someplace.
here, wind energy is combined with hydroelectric energy. Aren't there any "power plants" which press air in the underground which can then be released by generating power? I don't know the english name for this kind of energy storage. But it would be applicable as well in flat areas. If there is a suitable geologic condition of course.
I know there are as well underground energy storages with pressurized air in the USA. There is one in north Germany.
Just a idea. Using renewables means diversification of energy sources.
That is compressed air energy storage, mentioned above by Roger Connor. I wrote an essay on it a few months ago:
Compressed Air Energy Storage
Seems to be a very good idea, but you have to have a place to store the compressed air.
The major problem is that you need a cavern in which you can store the compressed air - and it needs to be big - as much as a mile long, and half a mile wide and hundreds of feet deep.
The other disadvanatge is that you have to have a ready supply of natural gas, in order to release your stored energy.
Depleted natural gas reserviors (or rock that could have held NG if there had been a source) seem the only likely pumpeed air reserviors. Excavacted old mines/quarries might work as well in special cases.
There just isn't that much spare cash lying around now and there will be even less in the future. Unless the cost can come way way down. Realistically the future looks like coal and nuclear with a minor assist from renewables.
The same thing would work with (for insance) gas or coal. Wind + nuclear (as much as it pains me to say this) works less well than wind + fossil, as nuclear plants have a lot of thermal and (more importantly) radiological inertia, and cannot be adjusted terribly quickly. The same things that make them safe (unable to spike quickly) also makes them unable to adjust terribly quickly (say, on the order of tens of minutes, though someone working at one of these facilities would know more accurately).
Generation capacity can be built in most cases for around $1/W, maybe more in some cases (I think the nuclear numbers throw around are generally about $2/W), and wind is also built for $1/W. However, with wind only getting 20% usage, on average it would cost more like $5/W, and require backup generation (hydro, as in Denmark, or coal and gas in the states) that would seriously increase the total cost.
Anyway, a big weathersystem can cover about half of the US, so I think even large countries wouldn't have vastly smoother wind output than denmark. Even if they do, moving electricity from Oregon to Florida when the weather demands it is no small task.
Wind can work as maybe 10-30% of capacity, but what about the rest? What would work well would be nuclear that can use the excess electricity to produce hydrogen. That would be useful primarily for things like fertilizer generation, and oil refining (I'm not a big believer in the hydrogen car, I think we'll get electrical cars first), and may reduce pressure on natural gas. This would work as the reactors could be run at 100% all the time, and when the wind blows, produce hydrogen, when it doesn't, cover the power demans.
It wouldn't work to just have wind and have it produce hydrogen when there's excess, as there would be times when wind output would drop effectively to zero, so other generation means must be able to supply essentially the whole electrical demand, and just use the extra power provided by wind for industrial applications that can be put off til later when needed. Hydrogen production, steel smelting, aluminum production, phosphorus production, etc...
If we simply accept the generation production cost you cite, then wind looks like a lousy option for $5 per actually watt of generation as opposed to coal at $1 or so. But, this totally discounts critical issues:
No it is not like that at all. PHEVs and BEVs will hopefully be the normal car that you buy. AC motor controllers like the ones from AC propulsion already come with V2G built in. The peak power requirement of your house would not exceed 10kW so a 80kW car motor controller would not even break into a sweat supplying your house. Also the cars would communicate over the mains electricity lines and not need a seperate connector. Even if this did not work out a GSM module in the car would not be very expensive.
Grid Tie solar panels are becoming more common and cheaper. Hopefully this will all become mainstream and cheaper as volumes build.
slaphappy - "Wind can work as maybe 10-30% of capacity, but what about the rest? What would work well would be nuclear that can use the excess electricity to produce hydrogen."
Wind/solar/tidal/wave in combination can supply far more than this. Wind alone would not be considered for the future power supply. You are right that we can make hydrogen with surplus energy however it is more efficient just to store it in Vanandium batteries as less is lost. Also we can still use fossil fuels just at a much lower level.
I guess all those coal fired power stations get switched on and off a lot despite the inter-connectors.
Per capita Energy CO2 emission from the DOE:
Denmark 10.94t of CO2/capita (DOE for 2003)
Sweden 6.27t of CO2/capita (DOE for 2003)
United Kingdom 9.53t of CO2/capita (DOE for 2003)
Germany 10.21t of CO2/capita (DOE for 2003)
France 6.80t of CO2 per capita (DOE for 2003)
Switzerland 6.00t of CO2/capita (DOE for 2003)
The US is of course a slightly exceptional case:
United States 19.95t of CO2 /capita (DOE for 2003)
(See here for more data: http://www.iaea.org/inis/aws/eedrb/data/FR-enemc.html )
Denmark - small country with lots of wind and coal fired generating plant.
Figure 13 of Sharman seems to show that while Denmark exports most of its wind energy it does not seem to import much energy from Sweden and Norway during the quiet periods. Thus, it does not seem that Denmark has managed to reduce reliance upon coal-fired base load. I think to convince the World about renewable wind energy, Denmark will have to start decommissioning coal fired plant and reduce CO2 emissions.
http://www.thomastelford.com/journals/DocumentLibrary/CIEN.158.2.66.pdf#search=%22horns%20rev%20perf ormance%20data%22
Power imports not included.
It seems to promote a reliance on coal and gas, which can be brought on quickly for when the wind is variable.
The fact that Denmark belts out more CO2/capita than the UK and Germany suggests to me that wind power isn't working at all, and we may be better sticking with coal, or better still going down the nuclear route like France!
I guess a society can use wind power for most of its power needs when it is ok to delay your work and errands for a day or two if the wind does not blow enough to charge a regions electrical wehicels.
Perhaps Denmark sells baseload coal power and intermittant wind power to the northern scandinavian countries and buys hydro for peaking?
And exactly when did nuclear power and the radioactive and toxic metals become "clean"?
Just two choice? Oh my, oh my. The powerdown option isn't worth considering eh?
(as it is with resource consumption, 1/2 fried may not be the death of us all....)
All forms of energy conservation and smart use of energy must of course be prioritised - but I see very little sign of governments being serious about that. In the UK, Heathrow Airport is being expanded, and their are plans to expand Edinburgh and Aberdeen airports - there is absolutely no sign of the UK government being serious about energy conservation - they are still stuck in 20th Century expansionist economic policy based on increasing energy consumption.
The world governements are supposed to be a function of the people. If the masses decide that powerdown is the option to leave something for future generations, then that will be the path taken.
The non-powerdown option will just work to destroy the planet in the continued orgy of consumption.
No more comment needed.
If the masses decide that powerdown is the option
The "masses" move but never "decide".
BTW, the "masses of asses" and TPTB are two sides of the same coin nothing usefull will come from them PO-wise.
Because I don't remember asking for your reply.
The fact that I "replied" to your comment does not mean I was talking to you.
Furthermore I need no license for moron-busting.
Enjoy...
You should learn to stop speaking of yourself in the 3rd person.
It is still impossible, and will probably always be, to deal with CO2 once it has been released.
Step 2) Wait while trees capture & sequester carbon
Step 3) Do something with tree where most of the carbon stays sequestered for a "long" time.
Step 4) Repeat
- Grow crop
- Char the crop to extract gas+wood alchohol+other nasty poisons
- take char and bury in soil (terra preta)
A bit shorter cycle than 'grow trees and do something with them'And hehe, hopefully no one starts using all that free charcoal. We'd better pack it in around the nuclear waste. ;)
Cost? One does not consider their own labor as a cost to the IRS :-)
Keep in mind that what I'm suggesting helps soil fertility, can get rid of probematic organic material (like pine needles - and instead sheds the turpines into the air) and can get rid of plant viruses/pests.
Other than the carciongines of the burning process, looks to be a win.
"In a diffuse-low energy society... EFFICIENCY of use will be paramount"
Thus whichever side you take on "the ethanol route"... it is ultimately a dead-end if, after all that effort... you are going to BURN it in an ICE... thus immediately wasting 70% of the energy as heat to the atmosphere...
I contend that a better use of crops (after food!!) will be as replacement for petro-chemical feedstocks.
And then... during the recent ethanol debate... I had a small revelation:
that if bio-feedstocks from crops are used to make useful materials (plastic replacements?)... then essentially, just as with the above example for WOOD... the carbon is being sequestered... for decades...?
Likewise with oil: let's use it for materials, not burn it!
Most carbon sequestration today is in the forms of landfills. The OECD grows trees (and buys them from the third world), makes them into paper, and then buries the paper and the carbon contained in landfills.
Well, the planet is also sequestering carbon by dissolving CO2 in the oceans, but that may have it's own problems.
I would just like to point out that a good balancing scheme will probably need the construction of serial dams. One upstream to produce electricity, another downstream to keep the water from going directly to sea, and to be readily available for back-pumping.
- Router - most have some kind of low-voltage power plug.
- Strip lights or LEDs
- Laptops
- Desktop PCs if using low-power CPUs (Pentium-M, VIA C7). You can get DC-DC converters Mini-ITX.com to supply the +12, +5 and +3.3 volts needed by most motherboards. My new server uses this.
- LCD Monitors
- TVs and DVDs
- Fridge
- Microwaves (You would need a large battery to make this work)
The advantage is that you can charge the batteries at night on cheap electricity or by solar panels/wind chargers.You wrote "This is one for the legislators."
I wont wait for them, by the time they get their asses into gear it will be too late. Im creating a site called "Low Energy Living" which should give people some idea on how to do all this stuff. More on that later.
Might you be better off waiting for technology to improve or am I missing something?
Thank you for pointing this out JN2. I don't have all my notes, but the 8k also included installation, a required upgraded inverter and more expensive wiring having to do with lower voltage required for battery backup. My summary was misleading. And maybe I was being overcharged in the estimate given. I was still concerned about having to replace the batteries so often. The hybrid car batteries seem to have a much longer life than what is currently used for PV systems. And congratulations on getting down to 8kw/day. We have gotten down to 9 without using electricity for hot water and hanging all our washed clothes on a line.
Sadly, I am far above the 10kwh/day level -- but am driving down (new appliances including SEER16+ system, sealing air leaks, insulation, all CFLs and now installing LEDs -- in addition to traditional demand reduction (putting systems on power strips and turning off when not in use, etc ...).
Maybe the utility company would pay towards the H2G (house to grid) system? Save them building additional peak capacity?
http://www.svk.se/upload/3756/SVKK030121.pdf
Not all of the planned grid investments are shown.
I would find it ideal to restart the Barsebäck nuclear powerplant in the southern tip of Sweden and build new nuclear powerplants in southern Sweden. That would remove the need for baseload power transfer from northern to southern Sweden making transmission line and hydra station capacity free for ballancing more wind power.
More wind power and additional nuclear power could then replace all the Danish coal power including the coal power needed for district heating if they use massive heat pumps such as those in use in Stockholm and convert old coal fired district heating powerplants to oil/gas/biofuel fired peak and emergency powerplants.
I think Denmark could become almost coal use free within 15 years with a doubling of the Danish wind power, new wind power in Sweden, 2-3 restarted or new reactors in Sweden, 2-3 DC-links and perhaps a pair of 400 kV AC links Copenhagen - Malmö if such long sea cables are practical and some reasonable uppgrades of the Swedish grid such as 400 kV lines over mostly farming areas and uppgrades with new poles and lines from 220 kV to 400 kV.
For such a time table to be realistic the steady change of opinion of nuclear power in Sweden needs to be a little faster, the time delays in the planning procedures needs to be halved, the Danes would have to let coal powerplants run down giving a capital loss and be willing to invest massiveley in wind powerplants and Danish owned nuclear power in Sweden.
A very intresting question is how peak oil will affect the long term price on coal, Denmark imports all its coal. My guess is that coal will become expensive compared with wind power and nuclear power. Denmark can produce wind power locally and importing the rest of the electricity is no different then importing coal. I do not propose Danish nuclear powerplants since they probably will be cheaper to build and run in Sweden where all the support authorities and infrastructure already is in place and we got a solid reputaton for free trade and foreign investments. But it is of course also selfish, more local nuclear power makes the grid more stable and provides some jobs. The last point and the utility of using excess heat for district heating might make it worthwile for the Danes to make the support infrastructure investment.
Now if I could get the pro nuclear and pro wind people to stop flinging dirt at each other...
Piper Alpha was the worst oil rig accident in the world and killed 167 people. Chernobyl was the worst nuclear generating plant accident and killed less than 50 people to date according to the extensive WHO report which can be found here:
http://www.who.int/mediacentre/news/releases/2005/pr38/en/index.html
For some reason the population, including politicians and many scientists I know, have a pathalogical fear of radiation. Long term exposure to the Sun is significantly more dangerous than exposure to relatively low doses of ioinising radiation. The Earth I fear may resemble Venus by 2100 if the World population does not overcome its fear of nuclear energy.
Regarding energy policies I got the impression that Norway, Sweden, Finland and Denmark togeather is of suitable size for cooperative planning. The area can absorb investments in 1500 MW chunks and is well integrated technically and culturally.
I think it would be a good idea to also have a nordic post peak oil planning with investments in rail, plug-in-hybrid outlet standards, low capacity +100 years life lenght natural gas pipeline network for biogass and long term Norewigan trickle production and so on.
Nuclear in Denmark?????
The general opinion in Denmark is that for the time being we can do without nuclear :-) We will try to get along with biomass, wind and conservation.
As Denmark at the moment is an fossil energy exporter (north sea oil and gas) plus wind/ biomass cogeneration, our CO2 emissions per capita are quite high. On the other hand- when the Hydropower dams are low in water in Sweden , Denmark export coal fired energy to Sweden. The energy used in Sweden thus ends up as Danish emissions. That is one of the beauties of national calculation. The reverse is also true- off course :-)
In terms of GDP energy efficiency Denmark is leading in Europe.
See diagram -EU member stares on top of page 40 in this EU document on energy efficiency. On top of page 44 Compared with USA, Japan etc.
http://www.energie-cites.org/documents/opinions/green_paper_text_06_2005_en.pdf
Regards/ And1
Also, would you like to comment on whether Denmark has managed to close any coal fired base load generating capacity - or plans to do so?
That probably used 10 year old data, which is pretty out of date, especially with regard to solar. Do you know if they included solar?
There are numbers for this in a great link provided by Toby Kelsey : Biological energy production
Only light within the wavelength range of 400 to 700 nm (photosynthetically active radiation, PAR) can be utilized by plants, effectively allowing only 45 % of total solar energy to be utilized for photosynthesis. Furthermore, fixation of one CO2 molecule during photosynthesis, necessitates a quantum requirement of ten (or more), which results in a maximum utilization of only 25% of the PAR absorbed by the photosynthetic system. On the basis of these limitations, the theoretical maximum efficiency of solar energy conversion is approximately 11%. In practice, however, the magnitude of photosynthetic efficiency observed in the field, is further decreased by factors such as poor absorption of sunlight due to its reflection, respiration requirements of photosynthesis and the need for optimal solar radiation levels. The net result being an overall photosynthetic efficiency of between 3 and 6% of total solar radiation.
P.S. I am repeating links because I noticed many times that some questions get asked repeatedly which were already covered (more or less) by previous postings.
Given the volume we are wading thru I don't think there is any other solution.
My back of the envelope calculations suggests that 100M acres of biomass could generate all of US electricity, at that rate.
Are you sure?
No, not my numbers, FAO numbers, see the linked page.
Plus, most likely it is for the raw theoretical calorific content of the total biomass of the area, including wastes and not taking conversion (in)efficiencies into account.
Well, the author seems to assume that our goal is liquid fuels. If the biomass were burned instead, it would include wastes, and there would be no conversion losses except for the heat engine loss, which I included.
It certainly suggests that biomass would work for heating and electricity production.
For electricity, if you had a mix of 25% wind, 25% solar, you could use 20% nuclear for baseload, and use 20% biomass and 10% hydro for balancing of the intermittency of the wind and solar.
This source seems to indicate you'd only need 20M acres of farmland for that.
Does this distinguish between wholesale (primary) energy and retail (secondary)? Typically there's about a 4 to 1 ratio (3 to 1 for electrical generation, 5 or 6 to one for transportation) of primary energy (heat, from coal, gas or nuclear) to secondary (electricity, vehicle motion). A country could go from coal electrical generation and gasoline transportation to PV and electrical vehicles, and reduce their energy use by 4 to 1, and yet be getting the same benefit (i.e., not really "power down" in the sense of getting less effective energy).
I wonder where the PV figure of 25 PJ came from? That works out to about 500W of PV per person, which seems like a very low maximum. That would require only about 3 sq meters per person of roof space, and only $3,500 at todays prices (which will drop a great deal fairly soon).
Given the lower co-efficient of friction for steel rolling on steel vs. rubber on concrete/asphalt, one can trade 20 BTUs of oil energy for 1 BTU of electrical energy in long distance freight transport.
They did studies of how these rail cars interacted with tunnel cross-sections for their 57 km long tunnel (finished in 2017, started ~2000) and built a "matched set".
With more expensive energy, rail freight may start paying attention to aerodynamics, as trucking has since the 1970s.
I have limited knowledge here.
Gratuitous affirmation unless you provide numbers and their sources.
http://www.iea.org/Textbase/stats/PDF_graphs/DKELEC.pdf
I would very much like to see, in detail, how Denmark could close its coal plants without resorting to nuclear power or natural gas. With numbers and sources.
That's only the case under a regulatory scheme wherein the grid must accept all wind input, even if it's more than the grid needs. If the ISO can reject excess wind than no amount of wind can destabilize a grid. Instead, wind becomes gradually less cost-effective,as more of it's output occurs during low demand periods when it's not needed. Of course, you could use a wide variety of schemes to make the excess useful: start selling to a larger grid, use storage: hydro, pumped storage, flow batteries, or charge electric vehicles; create hydrogen for stationery fuel cells, smelt aluminum, etc, etc.
There are a lot of options, if you use a little imagination.
Amazing framing.
Now, this 'low doses of ioinising radiation' you speak of, is this while you leave an area that has radiation?
You speak of the deaths from Cherbobyl, yet you ignore the abandoned land-space, the shortened lives....why is that?
For nuclear power to work as practiced, you have to have humans who design, build and operate the plants to not screw up or cheat on the specs in some way.
For the radioactive waste to be managed safly, society needs to function to guard such wastes.
Oh, and lets not forget the sociapaths who would use the leftover parts of the nuclear fission cycle as weapons. Or, use the reactors as a point-source weapon.
When you have actual answers for the above, then the analysis of "pathalogical fear" might have a chance of being correct.
http://www.rumormillnews.com/cgi-bin/forum.cgi?read=92597
http://www.who.int/mediacentre/news/releases/2005/pr38/en/index.html
On the one hand I would not want to trivialise the scale of this disaster. But on the other hand I feel that for many years I have been lead to believe it was much much worse in terms of death toll than seems to be the actual case.
The WHO report suggests that more people died at Chernobyl from worrying about the effects of radiation than actually died from radiation itself. Those who lost objectivity therefore have a lot to answer. Chernobyl, a badly designed and badly run reactor, I believe was responsible for the termination of civil nuclear energy development throughout the OECD, increased reliance on fossil fuels and the consequential possibility of climatic disaster later this century - that is the real cost of Chernobyl.
It is a fact that 10s of thousands of people die every year from skin cancer caused by over-exposure to the Sun. And yet our politicians, whilst scare mongering about nuclear energy, do nothing to stop people flying to sunny lands, pumping CO2 into the atmosphere, for the purpose of scorching themselves beneath our solar reactor. This is a pretty damming double standard.
You are keen to highlight theoretical dangers of human involvement in running nuclear power plants. In fact it seems possible that nuclear has the best safety record of all power generation options:
http://www.321energy.com/editorials/mckern/mckern031306.html
No doubt there are contributors to TOD who may provide more comprehensive information on the actual safety statistics. But if it is the case that nuclear has the best safety record why are you trying to talk this down?
But I'm afraid that in the meantime Norway has turned into California where BANANA is concerned. In other words: We need those coal power plants.
And it's really sad since Norway could potentially provide for all its energy needs through a combination of wind and biomass, in addition to an upgrade of existing hydro power plants from baseload providing units to peak load providing units.
Personally I would welcome a nuclear plant in Norway, but in light of our wind resource I think it should be unneccesary.
And I thought : they now use huge amounts of electricity pumping water to keep the polders dry... and they generate electricity with wind turbines... surely some mistake?
Perhaps a Dutch reader can comment on how all this integrates? I guess the Dutch must have a lot of expertise in pumped storage and the use of the tide, etc...
Wind/solar power for agricultural pumps, for example, make sense as these do not have to run 24/7 in most areas ... Figure out what parts of energy requirements can be fit to variable power sources and marry them directly to the availability of that power ...
Would seem to be straightforward ... yet another reason for smart grid ...
Every source of electricity, renewable or not, has its issues. Coal and gas have CO2. Gas and oil have supply-import-dependence. Nuclear has waste and security. I could go on.
Hydroelectric power alone provides a means of storing this oceanic/climatic renewable energy for use when it is most needed making Hydro an invaluable source of electricity.
No, this is incorrect. Compressed-air energy storage (CAES) is an option that is potentially available in many areas. Same for pumped hydro storage. Also, many utility systems can accommodate substantial amounts of variable power (for example, wind) because they have gas-fired generators that can ramp up and down as needed. All utility systems have to deal with the variable ebb and flow of demand throughout the day, so variability is not a new problem.
The current absence of a means of storing wind energy leaves electricity grids at the mercy of the weather and critics have long since pointed out that wind energy cannot provide a grid base-load.
Furthermore, it cannot be relied upon to provide peak electricity production. So what is the point in having wind energy? It has seemed to me that wind's primary purpose has been to provide politicians with a feel good factor and grounds for claiming green credentials.
First, as mentioned above, variability is nothing new. When demand goes up or down, what do utility systems do? Just give up? No, they adjust generation as it is needed. Adding wind energy into the generating mix changes the equation a bit, but usually only modestly up to fairly significant levels (10-20% of all generation coming from wind).
Second, wind energy does provide some "capacity credit" (reduce the need for conventional baseload). The amount varies depending on how closely the wind speed profile at a given wind farm matches the electricity demand profile of the utility system. Usually, wind's capacity value will be something like 10% to 30% of its nameplate value--that is, adding 100 megawatts (MW) of wind will add
the same amount of reliability as adding 10 to 30 MW of fueled generation.
Third, even if wind provided no baseload capacity equivalent, and could not be relied upon at peak, it would still have value as a fuel-saver. It's renewable, and reduces the need for nonrenewable fuels such as coal or gas. In the process, it also reduces global warming pollutant emissions.
A recent study of the impact of adding 3,000 MW of wind to New York's utility system for NYSERDA [the New York State Energy Research and Development Authority] found that wind's capacity value was only 10% (that is, adding 100 megawatts of wind to the NY power system would only add as much reliability as adding 10 MW of fueled capacity). Other studies in the U.S. have found higher values--a major study of the Xcel North system, for example, gave wind a capacity value of 27%. The NYSERDA report also says:
"Energy produced by wind generators will displace energy that would have been provided by other generators. Considering wind and load profiles for years 2001 and 2002, 65% of the energy displaced by wind generation would come from natural gas, 15% from coal, 10% from oil, and 10% from imports. As with the economic impacts discussed above, the unit commitment process affects the relative proportions of energy displaced, but the general trend is the same regardless of how wind generation is treated in the unit commitment process. By displacing energy from fossil-fired generators, wind generation causes reductions in emissions from those generators. Based on wind and load profiles for years 2001 and 2002, annual NOx emissions would be reduced by 6,400 tons and SOx emissions would be reduced by 12,000 tons." See The Effects of Integrating Wind Power on Transmission System Planning, Reliability, and Operations: Report on Phase 2: System Performance Evaluation: Executive Summary.
You can access the NYSERDA report and other similar studies and information on wind's impacts through the Utility Wind Integration Group site.
Wind supplies 16% of Denmark's electricity.
The latest number I have seen is 23%.
The load factor of the Danish wind carpet is only 20%. In other words, for every 5 MW of installed capacity the wind carpet on average produced 1 MW during 2003. Information on the cost of installing wind power is given here.
On average 1kW of installed wind power costs $1000. Therefore, to get 1 MW return, 5 MW costing $5 million needs to be installed.
Actually, costs are currently higher, due to a worldwide shortage of turbines--more like $1500/kW--which brings up a useful point. ~60,000 MW of wind was installed worldwide at the end of 2005, of which only 3,100 MW was in Denmark, making Denmark less than 6% of the total.
Also, the delivered cost of electricity from fueled sources is inherently unpredictable, since it depends on what happens in the fuel markets. As we have seen recently, fuel prices are not always stable. Natural gas prices are currently about triple what they were prior to 2000, and they have been even higher recently.
I find the high variance in output surprising as I'd always assumed that wind in one location would compensate for no wind at another and this should result in some smoothing of output. In Denmark it seems that the wind blows everywhere at once and this may be due to the flat topography and relatively small area. In larger, topographically more variable countries it might be expected that greater smoothing of output will occur.
Correct. This is a flat area and it is not that large geographically (3,100 MW of wind can be installed on just ~300 square miles of land). When a front comes through, it has a broad effect.
Still, part of the issue also has to do with Denmark's power system. 20-25% of the electricity is provided by wind and another 20-25% is provided by small CHP (combined heat and power cogeneration) systems, which the utility system does not control (that is, they are not "dispatchable"). This complicates the problem of controlling the overall system.
Sharman also points out that some of the variance in Danish wind energy output gets sunk into the massive German grid that lies to the South. The variance in the Danish wind supply is only a problem for Denmark because wind energy represents a significant proportion of the total grid supply--16%. Any country wanting to rival the Danish wind model will have to either develop a grid balancing system or
develop energy sinks within the grid or both.
Or, it will have to be bigger than Denmark. 3,100 MW of wind provides 23% of Danish electricity. In the U.S., 10,000 MW is less than 1%. Problems will still be encountered in the U.S. in utility systems that 1) have few links with their neighbors and 2) have few flexible (gas or hydro) generators, but large integrated systems like the New York Power Pool (NYPOOL) or the Pennsylvania-New Jersey-Maryland Interconnection (PJM) should be able to accommodate more wind than Denmark without difficulty.
A few weeks back some TOD engineers were throwing around ideas about using the batteries of electric cars as sinks for wind energy. This sounded a great idea. Would it also be possible to develop water-heating systems in public buildings to store heat when the wind blows?
Yes, and there are other options to increase demand flexibility, like ceramic heaters and furnaces that can store electricity as heat and release it over time.
Would it be possible to use wind energy to actually pump water back into hydro dams using existing pump storage schemes?
Pumped storage typically refers to a closed system without a dam. Water is pumped into an enclosed area (for example, an underground cavern) and allowed to flow through hydro turbines when electricity is needed. Any electricity source can power the pumps, so yes, wind could do that.
HOWEVER, most utility systems in the U.S. have little need for specific storage dedicated to wind, and such dedication would dramatically increase the cost of wind. A simpler answer is more transmission lines and linkages. This boosts the overall reliability of the entire utility system while making balancing problems easier all round.
Denmark has no indigenous hydroelectric power but has managed to negotiate a power balancing agreement with Scandinavian cousins to make their wind carpet work. Larger countries such as the US and the UK that have extensive hydroelectric capacity must surely manage to engineer a power balancing act between their wind and hydro generators.
As the foregoing indicates, this is not correct.
Regards,
Thomas O. Gray
American Wind Energy Association
www.awea.org
www.ifnotwind.org
Enclosed caverns are a rarity. I have never visited any pumped storage sites with one and cannot name a specific example ATM. I have seen:
- Pumped storage from a lower reservior, previously built, to a mountain top reservior (a dimple with a low dam).
- Between two reserviors in a chain of reserviors on a river.
- From a natural lake or ocean and a speciality reservior on a nearby mountian or hilltop. Special lining is needed for salt water (and hydro equipment is more expensive).
I recently talked to Austin Energy and they are concerned about the limits of wind power in their system. I suggested pumped storage as a solution.Pumped storage can take five 5 cents/kWh wind power and turn it into four 35 cents/kWh peak power (#s from Austin Energy).
I STRONGLY advise AWEA to reverse their stance. Wind plus pumped storage is a more economiclaly viable solution in many markets than wind alone.
I don't understand the AWEA position on this. I'm a bit of a sceptic on wind, but if balancing wind with hydro can make it work and if using wind to pump hydro stations works as well then I could be converted to an enthusiast.
Euan Mearns
aka Cry Wolf
Time is an issue ATM. Taking care of my father as he rehabs from knee replacement surgery.
Best,
BTW, "Run-of-river" schemes have little environmental impact, and little storage. Take water when it comes down the river.
Enclosed caverns are a rarity. I have never visited any pumped storage sites with one and cannot name a specific example ATM. I have seen:
1. Pumped storage from a lower reservior, previously built, to a mountain top reservior (a dimple with a low dam).
2. Between two reserviors in a chain of reserviors on a river.
3. From a natural lake or ocean and a speciality reservior on a nearby mountian or hilltop. Special lining is needed for salt water (and hydro equipment is more expensive).
Hmmm, you are entirely right and I am entirely wrong. Apologies--it seems that underground pumped storage is still a techno-dream. Somehow I had the impression that the Bath County Pumped Storage station in Virginia was underground, and it is the newest big one I had heard of.
I recently talked to Austin Energy and they are concerned about the limits of wind power in their system. I suggested pumped storage as a solution.
Pumped storage can take five 5 cents/kWh wind power and turn it into four 35 cents/kWh peak power (#s from Austin Energy).
I STRONGLY advise AWEA to reverse their stance.
We don't have any "stance." I'm just telling you what I think the facts are. Hydro capacity is great for balancing wind. So is pumped storage, if it's already there. Can a utility system add wind and do without either? Yes. Do they help? Yes.
Wind plus pumped storage is a more economiclaly viable solution in many markets than wind alone.
If pumped storage is already in place, then it can indeed reduce the cost of integrating wind. Otherwise other approaches need to be explored. Utilities may have more economical things to do with storage than balance wind--in particular, running baseload coal and nuclear plants all night when demand is low and using the stored power to meet peak demand during the day; and combining wind and new dedicated pumped storage at least doubles the cost of the electricity.
Regards,
Thomas O. Gray
American Wind Energy Association
www.awea.org
www.ifnotwind.org
I disagree, and Austin Energy is looking into it.
Pumped storage will, of course use any excess 3 AM base load power; be it wind, nuke, coal, geothermal or landfill gas.
I suspect that a combination of wind & hydro pumped storage (say 8:1 to 10:1 ratio in nameplate) could supply peak power for significantly less than 35 cents/kWh as well as shoulder power. 70 cents/kWh (doubling the cost of peak power) seems unreasonable.
A "package deal" of wind & pumped storage might be attractive than wind alone "in some markets". Sell to the peak market and sell spinning reserve as well.
Vanadium flow batteries have the same problem. OTOH, though wind power at $.11 would be substantially higher than coal or nuclear, it has none of their externalities, and is perfectly livable as a cost on which to run a civilization, demonstrating that wind with storage could provide a very large % of electrical generation if necessary. I agree with Tom Gray, I think other things - geographical dispersion, demand management, especially with plugins/EV's - will solve most of the problem.
see http://www.newswire.ca/en/releases/archive/August2006/30/c9631.html
If you charge-discharge daily, you'll get to the 500 cycle life of lead-acid in less than 18 months, and have to replace them. I believe the flow batteries have effectively no cycle limit, which cuts their effective cost by at least 80%.
(you) Enclosed caverns are a rarity. I have never visited any pumped storage sites with one and cannot name a specific example ATM. I have seen:
1. Pumped storage from a lower reservior, previously built, to a mountain top reservior (a dimple with a low dam).
2. Between two reserviors in a chain of reserviors on a river.
3. From a natural lake or ocean and a speciality reservior on a nearby mountian or hilltop. Special lining is needed for salt water (and hydro equipment is more expensive).
Hmmm, you are entirely right and I am entirely wrong. Apologies--it seems that underground pumped storage is still a techno-dream. Somehow I had the impression that the Bath County Pumped Storage station in Virginia was underground, and it is the newest big one I had heard of.
I recently talked to Austin Energy and they are concerned about the limits of wind power in their system. I suggested pumped storage as a solution.
Pumped storage can take five 5 cents/kWh wind power and turn it into four 35 cents/kWh peak power (#s from Austin Energy).
I STRONGLY advise AWEA to reverse their stance.
We don't have any "stance." I'm just telling you what I think the facts are. Hydro capacity is great for balancing wind. So is pumped storage, if it's already there. Can a utility system add wind and do without either? Yes. Do they help? Yes.
Wind plus pumped storage is a more economiclaly viable solution in many markets than wind alone.
If pumped storage is already in place, then it can indeed reduce the cost of integrating wind. Otherwise other approaches need to be explored. Utilities may have more economical things to do with storage than balance wind--in particular, running baseload coal and nuclear plants all night when demand is low and using the stored power to meet peak demand during the day; and combining wind and new dedicated pumped storage at least doubles the cost of the electricity.
I e-mailed two experts about your conversation with Austin Energy--one who is an expert in general and one who knows more about Austin Energy's specific situation. Here is what they said:
#1: "When folks say stoarage is the answer to wind integration, they are almost always overlooking a cheaper answer (usually, first, tariff reform, then transmission). In the case of Austin, think it is transmission."
#2: "The answer: it depends - existing vs new? We don't have opportunity for new pumped hydro around Texas - have you seen our puny rivers? AE has looked into CAES but it's expensive and we already have a lot of excess capacity in ERCOT.
"Transmission serves more than just wind power, so may be a better option for building a robust system.
"Texans can take advantage of the opportunity to store natural gas, not air. We have an already built gas system. 72% of the capacity in ERCOT is natural gas, and we have the gas storage in underground caverns already. Why build more storage?"
Regards,
Thomas O. Gray
American Wind Energy Association
www.awea.org
www.ifnotwind.org
When demand goes up or down, what do utility systems do? Just give up? No, they adjust generation as it is needed.
I think that says everything. With wind they cannot adjust generation as needed - unless secondary energy storage has been built and can be drawn down. With a 20% load factor for wind, cost (financial and energy) of building secondary storage, and energy losses at energy storage and energy release stages, sceptics I beleive will continue to be sceptical. That is where I see the beuaty of balancing wind - hydro.
As the foregoing indicates, this is not correct.
You lost me on that one - Denmark does not have any indegeneous hydro - but the UK and the US does. Are you saying that these bigger countries can accept 20+% penetration of wind without any form of power balancing just because they are big. If you look at Figure 13 in Sharman's report you see that Denmark exports essentially all of its generated wind power - why do they do that?
There is nothing wrong with using hydro to balance wind, I'm all for it. It's just that there are a number of other ways to "skin the cat."
Also, (1) load factor for wind in the U.S. is more like 30% on average, and (2) 30% load factor does not mean a plant is generating only 30% of the time--at a typical U.S. site, some electricity is generated 65-90% of the time.
You lost me on that one - Denmark does not have any indegeneous hydro - but the UK and the US does. Are you saying that these bigger countries can accept 20+% penetration of wind without any form of power balancing just because they are big.
More or less. Here is the basic mantra, taken from slides prepared by an expert on these issues for the New York Independent System Operator (NYISO), the company that operates New York's transmission system:
"- Limits [to wind "penetration," or share of electricity generation] are economic, not technical (reached at ~40% penetration on annual energy basis)
"- "Costs" are de minimis at "low" penetration, modest at "medium" penetration, and mitigatable at "high" penetration levels with "hockey stick" shape.
"- Order of mitigation actions is generally: software/IT; then curtailment; then transmission; then generation; then storage.
"- Value of "low," "medium, " "high" principally depends on: [1] Size of "region"; [2] Type of tariff; [3] Stiffness of grid; [4] Flexibility of other generation.
"- New York is "average to above average" on this scale. Should have no difficulty reaching 15-25% penetration without major capital investment to deal with intermittency."
System size matters because the bigger a utility system's control area, the more flexible generating units it can draw on to balance supply and demand.
If you look at Figure 13 in Sharman's report you see that Denmark exports essentially all of its generated wind power - why do they do that?
If indeed this is correct, it's because (1) there is a very poor match between the profile of wind speeds and the profile of demand, (2) Denmark is short on natural-gas-fired power too, and (3) Denmark's wind farms are installed in a relatively small geographic region.
Regards,
Thomas O. Gray
American Wind Energy Association
www.awea.org
www.ifnotwind.org
Denmark is not one nation in regards to it's grid. ~80% of the wind is in the lightly populated West/Jutland. The farmers there do not use much.
So Copenhagen imports electricity at the same time that Jutland exports power. Or, put another way, electricity goes through Norway & Sweded to get to Copenhagen "much of the time".
I have a loose understanding of the Nordic grid, so I am not 100% sure of this; just 96% sure :-)
I'm glad to hear that you are in favour of wind-hydro balancing - I was beginning to wonder. In terms of using a number of ways to skin the cat, in Scotland we have an extensive and growing hydro infrastructure that just happens to be located in the windiest areas. So I wonder if this may be the best solution for us. But as you say, other areas may need to skin the cat a different way.
Also, (1) load factor for wind in the U.S. is more like 30% on average, and (2) 30% load factor does not mean a plant is generating only 30% of the time--at a typical U.S. site, some electricity is generated 65-90% of the time.
A number of posters have pointed out that load factors are higher in other countries. However, Sharman (Fig 7) points out that wind developers develop the windiest sites first. With increasing penetration, less windy sites need to be developed, and there is negative correlation between capacity / penetration and load factor. This makes intuitive sense to me so I will choose to believe it. This is analagous to miners high grading mineral deposits. The load factor is low in Denmark as a direct result of the degree of wind penetration.
This would eventually apply in the US, perhaps, as development is being done by large, mobile investors (though it might take awhile, as the wind potential of around 2 TW leaves a lot of room for growth).
OTOH, in Denmark a lot of the investment decisions are done by local coops. They don't look around the country, they just analyze whether it makes sense for them - go, no go. So a lot of the installations are going to be suboptimal.
IMHO, two opposing trends.
In reality whether wind has a load factor of 20% or 30% may make a difference to the economics of wind developments but to my mind it is using that 20% or 30% effectively that is most important.
He's just speculating. There was a recent study of UK wind which found that wind is pretty consistent in the overall UK currently.
Regards,
Thomas O. Gray
American Wind Energy Association
www.awea.org
www.ifnotwind.org
- Capacity factor is 27% not Denmark's 20%
- Wind power in the UK produces, on average, more electricity at times when demand is highest, and less electricity when demand is low
Source: University of Oxford: Environmental Change InstituteWhile we could replace all carbon and nuclear power in the US in nameplate terms by building lots of interconnections and using the hydroplants to smooth out the relatively rare times when the wind isn't blowing anywhere in the US (about 1% of the time, IIRC), or even when the wind isn't blowing in half of the US (about 10% of the time, IIRC), we still have to remember that hydro is not the only use for dams.
We use it for agriculture, then for power, then for recreation, then for flood control.
Fishermen don't like it if you reduce hydro flow by 90% to save the water for later. It's bad for the fish. Fishermen also don't like it if you expand hydro flow by 900 percent when they are standing on a rock in the middle of the stream. It's bad for the fishermen.
So replacing coal by wind is just barely doable. It's more economic if combined with solar power, but you still want to have some coal. Wind, solar, and methanol plants with byproduct gas turbine power from the methanol plants is the best mix you are going to get.
Of course, you could go completely carbon free if you want to increase the 1% of your money that goes to power and fuel to say, 5%, by going to electrolytic methanol production from wind and making electricity essentially a byproduct of gasoline production.
Just tell me which 5% of your money you want to give up. Cable? McDonalds? Organic food? NPR?
Wind is only one element in the renewable power system of the future. We have to make the grid smarter so CHP plants are dispatchable. We also can make large domestic loads variable and able to be cut in and out on demand.
Solar thermal also has a large future. Many remote areas are extremely sunny and these can be used to make hydrogen or fisher-tropch/sabatier H2 with CO2 to make methane, methanol or other liquid fuels. Solar thermal can also supply electricity directly. Tidal and wave energy is just starting.
The chances of wind not blowing while the sun is not shining and the sea is calm and the tide is not running everywhare at once is much much smaller than just no wind.
A balanced smart grid will use whatever it has to supply demand with whatever it has at the time. It will turn off large loads to customers that pay lower tarrifs and agree to this. It will use whatever storage it can. It will try to predict the wind and sun using weather forcasting to make sure power is available. Fossil fuels allow us to be really dumb about power generation. You really just burn a gas or a lump of coal and power comes out. It does not matter if we waste most of it because we think that there is plenty more where that came from. Renewables are not like that, there is not enough of them to waste, so we need to be much smarter about using them.
In the end however there may be times when there is just no power. We are now paying the price for 24 X 7 power - climate change and extreme vunerability to energy shortages. To ensure our long term survival beyond the life of one power source, we may just have to accept that sometimes there is no power and we cannot do what we want to, when we want it.
Use HV DC lines to places distant from pumped storage. And get ~20% of our electricity from nuke ?
Alan, is it really that straight forward? Do you have any links to put more flesh on this?
First, I discovered that ~20% to 22% needs to be nuke.
From memory (notes at home, not here with parents)
Conservation/efficiency/solar water heating reduce demand to 80% of today.
52% Wind (max development of summer peak areas)
22% Nuke
12% Hydro
-19% Pumped Storage
+15% Pumped Storage
18% Geothermal, Solar Thermal/PV, BioFuels, Tidal, etc.
- Introduce a master plan for energy saving
- Plan for electric transportation - so need to aim to expand electricity production
- Balance wind with hydro until wind = 70% of hydro capacity
- Introduce a master plan for energy storing throughout the consumer system
- Aim to modify consumer habits (by education, legislation, tax and technology) to use power when it is available as opposed to when it is most convenient.
- Introduce other renewables (in Scotland most likely marine current and tidal) to the mix
- Expand pumped storage
- Expand installed wind capacity
And at that point review the master plan to see if you can go on to another level.I think if Scotland reached a point of 50% Nuke and 50% renewables that would be a major achievement - and not a bad starting point for surviving the post-peak oil world.
Electric rail is so efficient that I doubt that any expansion will be needed. In the US, replacing 1 million b/day should require a bit less than 2% of our electrical consumption.
I think that 1 MW of pumped hydro can support (nameplate) 5 or so MW of wind turbines quite nicely. Dam hydro is almost as good as pumped storage; run-of-river hydro has little value when balancing wind. Sales of surplus power to the English is also good.
Having interruptiable consumers of electrical power also expands the wind potential.
A HV DC link to Iceland would be "interesting". Large hydro there :-)
In the long run I would decrease wind and nuke, and increase solar and biomass.
Solar complements wind nicely, and is less variable.
Nuke is reliable, but has the same around the clock pattern as wind, while solar fits demand better than either.
Biomass (burned for electricity) would help with energy storage, and I think would be cheaper and more practical than pumped storage, though both would be good.
In the long run I would suggest:
35% wind
35% solar thermal & PV
12% hydro
18% biomass
add pumped storage as necessary, perhaps -15% and +11%.
This would be combined with HV DC grid, decentralized demand management, charging of plugins/EV's with G2V & V2G, flow batteries, hydrogen for stationery fuel cells, etc, etc.
Therefore, wind will be a generally cheaper source of MWh and for this reason should dominate a renewable grid.
Yes, wind has it's disadvantages* but one can work around that.
* At Hydrovision, hydro was shown as a cold, frosty beer with a good head of foam in a cold glass mug. All the "extras" one could want for beer :-) Wind was a warm, flat unappealing beer in a plastic cup. Still beer, but without all the nice extras !
I think you're right...for the centralized grid.
But, solar can be installed at home or business, and competes with retail prices, not wholesale. Therefore, under a certain price point consumers (business & residential) will run away with solar.
It will be interesting to see how the grid copes with this. Likely it will include changing pricing to discourage local generation (the opposite of net-metering), if the utilities have their way, but ultimately I don't think they'll succeed, if only because local storage will likely get cheaper, and local generators will be able to leave the grid if the utility pricing gets too punitive.
I project the installed base would be something around 33GW, which is around half of the current world installed capacity of wind power. At that rate solar would catch up with wind's 2005 capacity in about 2012, putting solar about 7 years behind wind. Solar is currently growing faster at 45% per year than wind (which I think is around 30% per year), and I think wind growth will level off long before solar. Actually, solar will probably accelerate as costs fall, like other consumer items like cell phones, etc., while wind probably can't grow any faster than 30%/yr, being a very large thing which has to be manufactured in fairly traditional ways.
The problem with long threads is locating a contentious post to reply to when the page jumps around. Wind->electricity->desalination via reverse osmosis is done at place called Rottnest Island in West Australia
http://www.rottnestisland.com/en/Education+and+Environment/Environmental+Initiatives/Wind+Turbine.ht m
Basically you wouldn't water your lawn at $A2.40 per 1,000 litres. A bigger plant on the mainland is under construction I understand. It just reinforces the point that renewable energy can do anything but the price may be too high.
Me again. I have a theory that I'll be researching in coming months. The theory is that during heatwaves when aircons are turned up fall blast that dams are run down well below seasonal refill levels. The reason is spot electricity prices which make it cheaper to use more predictably priced fossil electricity later in the year.
There is anecdotal evidence is that a high voltage direct current (HVDC) cable connecting my local hydro to the coal fired grid is being used this way. In autumn when dam levels are still low the hydro will re-import coal fired electricity. It helps profit but does nothing for clean and green.
The GW friendly alternative (as others point out) is to use less when you have less i.e. learn to live without the aircon in summer. I can't verify this til later in the year when the HVDC scheme has operated for 12 months.