http://www.kunstler.com/excerpt.html

I can't speak knowledgably about solar or any of the alternatives to oil/ng. However, it seems to me that what they all have in common is a far greater dependence on high capital intensity and high tech. Therefore they depend on a complex and specialized infrastructure. But it seems to me that this is precisely what's going to be hard to maintain at a certain point down off peak.

Here I think there is a really big unknown: once the hydrocarbons are mostly used up, how much of our infrastructure that supports high tech and high capital intensity will be sustainable? I tend to believe, but can't come close to proving that we'll have to back some considerable way off the way we operate now. Shumacher's "small is beautiful" in some form may come into it's own.

The powers-that-be strongly prefer the capital-intensive solutions and are quite hostile to the opposite. Maybe the most flagrant example is where some western owned water companies in third world countries have forbid people to collect rain water.

Odum liked tacking the 'how much knowledge is embedded in this product' and as such, PV to electrical power will always be expensive eMergy-wise.

If one applies a 'time value' to electric power, the conversion of a photon to electrical power via PV is the shortest.   Wind/Hydro is shorter photon->power conversion than plant->oil/alcohol->power and that is shorter than wood->power or coal/oil-> power.   eMergy has an ability to track time-value of a photon, but I've not seen a model of it.  

And last I checked, nobody had invented electric-powered bulldozers, trenchers, trucks, scoops, etc.

Check again.  In Milwaukee WI, the earthmoving machines made there are electric.

Also, once a power source like solar is started up, it requires very little oil or other variable priced fuel to keep it going.  Granted - there have to be replacements, but compared to say a gas-fired generator, the input is much smaller.  Solar might be a great solution for home use during "the coming collapse."  Here in Atlanta, it is just about the only choice.  Timing may be everything - I am planning on buying a small system right before the oil price shocks makes the manufacturing costs start to increase.  I am also hoping for the blessed solar "technology" savior, maybe organic cells.  Lets see how well I am able to "time the market."

Also, comparing the costs and rewards of anything requires that everything be put in terms of its "Present Value."  To do otherwise would be comparing apples or oranges.  Many people avoid this and calculate energy production costs using only an "instantaneous" production cost.  However, volatility is very important because it relates to the "risk" that one has for a particular energy production method.  Leaving out this risk makes fossil fuel methods seem much more economical.  
The following is an example of a present value calculation that shows wind power as a much greater deal than fossil fuel methods when the risk is considered:
http://www.earthscan.co.uk/news/article/mps/UAN/71/v/3/sp/
And, one of the results of "Queuing Theory" is that when the supply of a resource becomes less than the demand (Peak Oil), then the output (price) becomes highly volatile.
In other words, we should expect significant economic impacts from the upcoming price volatility of oil, in addition to the high average cost.  My little (future) home solar power system may help my family some.

The Germans are using all PV because of the latitiude they are at but sunnier locales can use some relatively low tech solutions (basically focussing the sun's rays to generate steam using reflectors - whcih scales up surprisingly well).

See this article for example on concentrated solar power projects in Nevada (and there are even bigger Stirling engine based plants planned for southern California):

http://www.renewableenergyaccess.com/rea/news/story?id=43336

Plus a lot of work is being done on thin film polymers and semiconductor alloys that are much more efficient at generating power than current PV technology. See this South African article for an example of one of these:

http://www.int.iol.co.za/index.php?set_id=1&click_id=116&art_id=vn20060211110132138C184427

In a decade's time every sun facing surface in the developed world will be covered in some sort of power generating device.

I suspect a country with plenty of sun, coastline and wind can run a reasonable economy using renewables, some fossil fuels (or nuclear). But you want to be driving a plug in hybrid rather than an SUV...

Yes, solar is unlimited in concept but very limited in reality for energy generation.

No, solar can not replace our existing energy usage or wants.

The big point however is that no energy solution will replace fossil fuels.  Not even nuclear IMO will give us all the energy, in all the forms, that we are used to now.

What we have to focus on first is How efficient can we use energy?  Conservation first, replacement of fossil fuels second.

Everybody wants to run conventional appliances and transportation using solar as a replacement.  This as many posters show mathematically is not going to work.  What we need to do ASAP is reduce energy consuption everywhere.  Then we will not need as much energy to do the same tasks and can use alternate energy sources (which are much less energy dense) instead of fossil fuel.

Search the internet for how to build or retro fit a house to solar and wind energy.  The first thing they recommend is installing the highest efficiency refrigerator, stoves, lights, water heaters, HVAC, etc.  Reduce consumption first.  At that point you need less storage on site, meaning fewer batteries, waterfalls, flywheels, etc.  With less daily consumption you also need less total generating capacity.  Lower Capital cost for solar cells and wind turbines.  When you need less generating capacity per hour or day there is a much better chance of having at least maintenance energy from solar and wind even when conditions are not optimal.

What I see as the number one problem today is that fossil fuel is still way too abundant and cheap.  We are not (yet) driving for the maximum energy efficiency in most peoples houses or daily lives.  

Only a coordinated program of energy reduction (conservation) dovetailed with solar energy (renewable production)makes any sense.  I see this as critical for transportation as well as creature comforts at home and work.  We currently waste as much energy as we use.  

It is a false premise to say we can't meet our energy needs using renewables, plus nuclear, plus very, very limited fossil fuels.  The reason it is a false premise is that we really don't have a good handle on what the minimum energy usage we need to maintain our society. (Not have all we want, but just meet ours needs and have some extra available from time to time).  We only know what the energy usage is required to maintain the existing system.  An energy replacement plan without an energy consumption plan will not work, as many posters have shown thermodynamically on TOD.  

The falacy of the Bush administration's energy plan (and most governments plans) is that it is only energy replacement.  It needs to be equally energy reduction, via a drive for efficiency and some total elimination.

I think when the direction of Oil and Gas gets more broadly accepted, and the prices concur, that these simplest ways of garnering some free heat will blossom with both commercial offerings AND do-it-yourself projects.  

Whether or not my Prophesying has any merit, I know that my house is pumping through about 7 gallons of No.2 Oil a day, for three dwellings, and that I have enough roof-area to curtail a great deal of it, if I can apply all the glass I've collected towards some 'technology' that's far simpler to understand than a basic car tune-up.

In acknowledgement of the Thanksgiving prediction, I bought my first, modest (40w) PV panel, charge controller and some batteries last December.  Appropriately, my purchase was delayed by about the same amount as the Prediction was recently adjusted.   It's enough to run a few lights here and there, maybe the Laptop.. but I really wanted to mainly have one decent panel in my possession in case a bigger hiccup in energy supplies triggered the predictable spike in PV prices and availability that I assume we'll see.  PV won't save us, and it won't replace what we use today for power, but we'll have the chance to really evaluate what needs to be done with electricity, and what can work with other energies.  I'm in Maine, why do I and ALL my neighbors in the Northern 60% of this Country have a Refrigerator running a compressor all winter?  If it's cold enough out, a better design would only be using a small sensor circuit and a heat exchanger to the outside.  Most of this stuff is NOT high tech. Just takes some thought.. and a bunch of motivation.  Aha! There's the energy shortage!