In Japan, people turn off their engines at red lights.  As a matter of civic duty, apparently.
A large portion of the wear on an engine comes at startup.  There is no oil pressure, so you've got more metal to metal contact.  I've seen several systems to reduce this - One is an accumulator tank that stores pressurized oil when the engine is running, and releases it through an electrovalve at startup.  Another is an electric oil pump.  Anyone know how the hybrids do it?
An electric oil pump would be a natural solution for a hybrid.

There is trend for electrifing all auxilary power uses such oil pump, cooling liquid pump, AC compressor and so on to improve the ability to control the running and energy use. This has also to do with a proposal for raising the standard voltage in cars from 12V to if I remember it right 72V to better utilise the power leads and so on to lower weight and cost in expensive copper and high amp semiconductors.

In cold areas I would add a heated thermos with cooling liquid for the plug in hybrids. It would be kept close to boiling at all times to be used for initial cabin and block heating after starting the car and befor starting the fueled engine. I would also insulate the motor block and add electric condensation removers to all windows. If you know beforehand when you need to start your car in a cold climate you can prehet the block better with a regular block heater and run a hot air fan in the cabin.

72V sounds about right, now if they would just speed it up to 300HZ like the aircraft did in WWII  That would improve everything considerably.  Think of all the new start up companys building the necessary equipment to run the stuff.  

Basicly on the same subject.  You can thank G.E.,WESTINGHOUSE, and PHELPS DODGE, to name three, for the elecrical system we have in place in the USA today.  Using 7200V to 120/240V leads to nothing but trouble as the Utility companys are learning.  Think of most of the rest of the world, using 33KV to 240/440V for local distribution, smaller everything.

Why change car power from DC to 300 Hz AC?

The voltage limitation is due to what can be done securely with the simple insulation in regular car wiering.
One problem is that low amp 72V light bulbs are less vibration resistant then high amp 12V light bulbs but since we anyway are changing over to LED:s and high performance electronically controlled "xenon" this problem is going away.

I guess it will take decades before the battery systems for energy storage in electrical cars and plug in hybrids is standardised since the technologies are evolving. I dont think anybody know the optimal voltage and battery shapes.

220V 0 Hz AC has become 230V and then 240V over here in Sweden. We have had some DC systems and manny different voltages in towns but three phase 230V/380V took over a long time ago since three phase AC made it easy to get power from far away hydro powerplants.

The oddest system is the 16 2/3 Hz single phase one for electrifed rail since railway electrification started with 15 Hz AC since it made it easier to build strong engines with the first generations of electric motor technology. It then went 50 Hz / 3 to use rotating converters from the regular grid to avoind building a separate railway grid. We are any way getting more and more of a separate 130 kV 16 2/3 Hz grid due to recent optomizations but these are richer times.

10-12 kV is very common in old underground wiering in towns and archipelagos. There are some 6 kV systems but that voltage mostly lives on as a standard voltage for generators. 3 kV has died out. 20-24 kV is probably the most popular in rural areas and is nowdays no problem at all for cabels and when the ground allows it these systems are being cablified to make them storm resistant. I dont think 33 kV is very popular at all. The next level in the grid hierachy is 70, 130, 150 kV for regional distribution and the highest level is 220 och 400 kV national grid and HV DC links.

A new system could be a few kV DC or fairly high frequenzy AC in slim coaxial type cables. Such has been suggested for building parallell emergency power grids in towns for UPS:s, cell phone sites and so on. None of those suggestions has as far as I know it been implemented. The ones who realy need it buy larger batteries, local generators and connections to more then one transformation station in the local grid.

Magnus,

We don't have decades.

Even if we did, we don't have infinity.

And why would we want to continue the failed paradigm anyway?

That Titanic, she would run a whole lot better if we changed the electrics over to the more efficient granzenhammer system. Yes indeedy-doody.

Full speed ahead! Damn the torpedoes!! There ain't no stinkin' peak oil!!

I feel like I'm hogging the slow pitches here ... somebody else want to take it?
There were plent of ships built after Titanic.

General electrification and having a grid is far from a faild paradigm. It will probably become even more important as fossil fuels get expensive, it is so far the most efficient way to coordinate the use of manny different power sources for manny different needs.

If you can figure out a better way of building a grid and electricity distribution you can in a resource strapped future "mine" and recycle copper and aluminium from old inefficient circuits to build the new higher efficiency ones. Perhaps it will be 2 kV DC to your doorstep instead of 110 V AC? I dont know.

The local grid where I live would live for some 40 years or so with minimal maintainance but the maintainance isent minimal, its being upgraded on several levels.

Thanks - I really need to become more concise.

Sadly, even your fairly straightforward explanation of what an electrical grid represents is likely to be compared to rearranging deck chairs on the Titanic, or some such.

As for 72 volt auto electrics - I have read about 24 volt fuel cells being currently built into high end BMWs - I don't know more than that really, except they seem to take up a good amount of trunk space, in addition to the lead acid battery for starting the motor. The electrical system seems essentially split into electronic and electro-mechanical subsystems.

Thank you for correcting my voltage error.
"General electrification and having a grid is far from a faild paradigm."

Indeed, at least in the U.S. (if not the rest of the world), the power grid has so far proven to be very fragile. Every year, it's knocked out locally by storms. And some of the bigger weather events can effectively remove the grid from a region (Katrina, the Columbus Day storm of 1962, etc.), requiring extensive reconstruction (which, incidentally, requires quite a lot of fossil fuels to accomplish).

The grid, by the way, is particularly vulnerable to electromagnetic pulse and other forms of attack. These days, a power outage means all kinds of economic disruption, largely due to shut-down computers and related networks. A blackout in 1956 had a lot less of an effect on commerce and day-to-day life than one in 2006, and a blackout in 1926 had even less of an impact than in 1956. It is probably unwise to increase our dependence on "the grid" any more than we already have.

Reliability over 99.9% is quite reliable.  Repairing the grid is more labor intensive than anything else.

Backup sources for critical infrastructure is not a bad idea.

"Repairing the grid is more labor intensive than anything else."

Indeed, it is quite labor intensive.

However, it is interesting to note that to replace things like power poles (which topple rather readily extreme weather) requires gasoline-powered equipment (transportation being one), not to mention the road infrastructure that's also dependent on a large input of fossil fuels for maintenance and repair. Roads that, incidentally, can also be broken by the same storms that ruin the power grid.

And, of course, to make new poles requires cutting trees, transport, processing, etc., generally done by people who reach their job locations via gasoline-powered vehicles...

Hmmm... A supply chain issue: At what price point will energy costs seriously begin to slow down repair and maintenance of the power grid in the U.S.?

I returned home to New Orleans 3 days after the 82nd Airborne would let me back in.  The smell still lingered.  My power had just returned that day according to a neighbor.  I saw LOTS of utility repair (electric, telephone, gas, cable( in the months after.  I went all winter w.o natural gas heat or hot water.

ALL economic activity requires oil. How many gallons to write Microsoft Windows XX ?  But labor was the dominant cost for repairs.  My informed guess, 90%.

Hello,
   you also left out the Northeastern ice storm of 1998, which many people involved in Y2K considered a fine foretaste of failing systems under extreme conditions.

   As for EMP, Congressman Bartlett presented a fine overview - the man really is quite the responsible pessimist. Of course, all of this is so 1980 that the nostalgia gets to be a bit much at times - I remember the 10 bomb scenario, where the Soviets would so utterly cripple America's oil infrastructure (imagine a well planned Katrina/Rita in terms of non-functioning oil infrastructure) that the choice would be to accept their blackmail (taking over Iran/Saudi Arabia, etc.) or mutual suicide.

   I think much of the point comes down to redundancy and maintenance - things which a profit oriented mindset tends to scoff at, until the system fails. Luckily, the American government currently has CEOs running it, unlike Germany, which has a chemistry PhD as Chancellor - strangely, various German systems do not seem to be failing in any noticeable way.

To keep with the theme here - I don't think chemistry is a failed paradigm either, but if you wish to discuss about CEOs and their paradigms, well, peak oil is a fine example of how many CEOs look at the world - maximum profit without regard to the long term is so much better than social responsibility. Tears of Allah indeed.

expat, Something to consider: A nuke isn't the only thing that can be used to generate a devastating EMP. A flux compressor with conventional explosives can be quite effective. Indeed, a car bomb, or van-bomb, coupled with a flux compressor, could take down quite a sizeable region. Power grid, magnetically stored data, fried computer infrastructure (say all those processors in our cars, and increasingly in other things we use in our lives), toasted.

The frightening thing about this is that, since the intention would be to generate an EMP and not necessarily cause much damage with the explosion, an EMP bomb could be transported anywhere and left to detonate (no suicide bombers required), say a park, garage, or neighborhood, and the EMP would still have a crippling effect on a fairly broad region.

I think we are at very different scales here. I am a 2nd generation Cold War kid, so to speak - for me, you can't even begin playing the game until you stop worrying about how accurate the megadeath rate is, because the difference between 290 and 305 million dead just doesn't really matter in any practical sense.

In other words, the 10 nuke EMP scenario was meant to do two different things - avoid the massive deaths which would make retaliation with a massive U.S. strike revenge, not suicide, and to so cripple an industrial society that apart from committing suicide, it had no other options.

I may add, this scenario was explicitly designed to remove the oil refineries in California, the Gulf Coast, and the Northeast - never think we are talking about new ideas here, except for the occasional brilliant insight or neglected observation being brought to light.

This fairly elegant Cold War nightmare hinged on oil, as did much of the late 70s and 80s strategic war planning.

And the major reason for EMP becoming so critical was the defection of a Russian pilot with his MiG to Japan in 1975? - the plane still used vacuum tubes, which seemed incredibly primitive or even a deception, until someone realized that this meant the MiG was immune to EMP. To be honest, I'm still not sure what the final verdict on the MiG was - deception, primitive, or proof that the Soviets would fight dirty by fighting clean in the ionosphere, so to speak.

> A nuke isn't the only thing that can be used to generate a devastating EMP. A flux compressor with conventional explosives can be quite effective

These devices do not put out sufficient RF energy to cause widespead damage. The largest devices constructed (about 2 tons) are capable of affect an area less than a 1km radius.

>say a park, garage, or neighborhood, and the EMP would still have a crippling effect on a fairly broad region.

This is incorrect. for a EMP device to be affective it must be detenated high above its target. These devices radiate RF energy in line of sight. if the pulse is blocked by a hill, building or other obstructions, it cannot affect electronic devices behind the obstruction. The RF energy produced by an EMP is mostly limited the lower bands ( < 300 Mhz) which limits its pentration through obstructions.

The stories hyped by the media, sci-fi, etc have exaggerated the potential of EMP. The story goes that a terrorist group gets a hold of a tactical nuke and detenates it high above the US disabling all of the country's infrastructure. Such a device would not be powerful enough to do this level of distruction. Even a large Multi-megaton device would not be affective enough, since these devices are implosion devices that pre-ionize the surrounding air which shorts out most of the RF energy before it reaches the ground.

http://www.globalsecurity.org/wmd/library/report/1988/CM2.htm

To disable the entire US infrastructure it would probably require a dozen or more medium yield devices deployed regionally. This would not be possible accept for the large nuclear powers (US, Russia and possibly China).

Just thought of a new metaphor:
Warning--metaphor alert!

My most pleasant trip ever was on the P. & O. steamship Aurora from Sydney to San Francisco in 1961. The Aurora was a hospital ship in World War Two.

She was, I recall, torpedoed and sunk.

Then she was raised and floated and flourished again for many years.

"Aurora" means "Dawn"

Ho, my goodness, can we raise civilization after we run her aground on Peak Oil and Global warming?

Why the heck not????

Well, seeing as how the Swedes have literally had centuries of practice surviving in what could be called rigorous climatic conditions, somehow I doubt they are likely to share your framework that we are all doomed anyways.

And someone talking about electrical systems in place for what in some cases has to be several generations isn't talking about some 'failed paradigm' - they are just talking practical electrical engineering, a subject which just happens to predate the automobile, and a skill humanity is unlikely to give up at this point. Most of us find the paradigm of light at night pretty comforting, especially those people living in a place with a few hours sunlight per day in the winter.

The Swedes don't have a failed paradigm - they have an industrial society which realistically approaches problems with the sort of hard headed pragmatism you would expect from people who have never had much margin for error. But as the Germans say, the Swedes 'cook with water too' - that is, they are still facing a number of problems, and they do not have magical solutions. They could very well be living in condition familiar to their 19th, 18th, 17th, 16th, etc. century ancestors.

The Swedes simply don't have the decadent luxury of talking about failed paradigms at their keyboards connected to a planetary data network, since they are making concrete plans to continue to maintain a level of civilization even as other peoples' paradigms fail around them. (I do think the suburban U.S. 'buy a SUV to commute 2 hours a day to pay the mortgage' paradigm is about to hit a brick wall, though.) And who knows - it just might work in Sweden, since they will actually being doing the hard work of trying to live in the world surrounding them, and not worrying about whether their paradigm might fail. The winter is just a touch too cold to allow a true back to nature movement, after all - they are likely to stick to a paradigm involving insulation, I'll wager. I'll even wager that the Swedes know how to build fairly warm housing to survive in, without any need of fossil fuel at all - after all, they did for centuries. German Fachwerkhäuser, ca. 15th century, are surprising well insulated (they beat a concrete house from 1950 hands down), and fairly easy to maintain over centuries using nothing but local materials and skilled human labor - or is housing also a failed paradigm?

Peak oil is neither the alpha nor the omega - it is just change. Messy, perhaps catastrophic change for some, but less so for those able to see the future clearly and meet it. And yes, the paradigm involving cheap oil is about to die - this is not exactly unknown to large number of people living in places like Sweden or Germany - but speaking broadly, those people are REALLY worried about climate change, not whether the price of gas is 3 euros a liter. The Greens in Germany wanted to make it 2.50 euro a liter in the late 1990s, by the way (though tricky to compare, call it 10 dollars a gallon)- obviously, their paradigm of expensive gas leading to conservation and alternatives was just another example of failure, since peak oil is coming. As if the German Greens hadn't heard that, sometime around their college days.

I think the Swedes also had a clue about this peak oil thing, sometime in the 1970s.

Calm down, the "decades" seemed to refer to hybrid/EV battery standardization. Fortunately, vehicles can be built without such standardization - Toyota's been building them for some time. After all, the user accessories are most in need of standards, and user accessories don't, and need not, run at the same voltage as the motor. So you can have 12V for the radio, your notebook computer, and so on, regardless of the battery and other system voltages. The rest is merely a matter of convenience for the manufacturer, who has already taken care of it.

Increasing oil prices will drive hybrid and electric vehicles in any scenario except for Mad Max doom, so one might as well get over that. People will not go back to stoop labor, walking, and peasant existence - if that's the issue - without a major, violent, revolutionary fight. And in any case there are too many people for that to work any more. And let's face it, many if not most - even, these days, in the less developed countries - are in no physical condition to live in some previous century. So if Mad Max ever comes, all bets are off and these discussions simply will not matter...

See this is why I'm glad I let you guys go first.  Very substantive comments.  I would have gone with the shallower observation that the opening declaration was not very strong, falling back from "decades" to "infinity" in two lines:

We don't have decades.

Even if we did, we don't have infinity.

LOL, we don't have infinity, what will we do?

Second, I think decades are the correct timescale for energy transitions.  Projects take decades to come on-line, and reserves take decades to run their course.

I'm not a cornucopian though, we should be listening to what those projects are doing so that we can start any decade-long transitions we need to make.  You know, as stated in the Hersch report.

Hello Odograph,

Full credit to fellow TODer MHeisler for this PDF link:

http://www.worldenergy.org/wec-geis/global/downloads/bea/BEA_Seminar1105_Drollas.pdf

I am especially interested in comments to frame 20, "Two Hubbert Curves of Conventional Output vs. Actual Global Output".

From frame 20:
---------------
Global crude oil production between 2003 and 2020 rises at a rate of 1.4% per annum (the CGES' base case for oil demand).
Thereafter, having peaked in 2022 at 86.5 mbpd, it declines at a rate that generates a cumulative output figure of 2,888 billion barrels (96% of the ultimately recoverable reserves) by 2100.
-----------------

My read:
**
He seems to be gently saying the world political & economic powers purposely modified the global burn rate giving us much more time [preventing an earlier peak in 1988 or 2008]; a slowly rising plateau until 2022.
*
**

My Question:  Can we take this as evidence of a Foundation at work since the early 70s?  Can a Foundation prevent a 2008 Peak [how will they do it?], or is Dr. Duncan's Olduvai Gorge Theory [Brink Plateau until 2008] the higher probability outcome?

TODer Darwinian suggests that Russia may hold the key to any near-term Peaking.  Will the G8 purposely acquiese to Putin's demand for retaining 'energy supply security' as the best future path to control monopolistic export pricing: thereby providing a mechanism to choke the global burn rate once again and timeshifting the Peak one more time as Drollas's HL graph clearly indicates?

I cannot wait until this G8 Conference gets started; I think it will be fascinating!

Bob Shaw in Phx,Az  Are Humans Smarter than Yeast?

I enjoyed flipping through that.  I'd have liked to have heard the presentation.

On the simple question of timescale, there are a lot of slides there that look at decade over decade changes.  Beyond that, the nature of changes since the 70's ...

My memory is that industrial societies mobilized in the 70's to reduce energy consumption, and that while that feeling of "crisis" has faded, we've continued on in a half-serious way.

They tell us that industry has remembered energy as a cost-cutting field and that might be a good part of it.  Consumers?  Pfft.  How many have compact fluorescents and SUVs?

IMO we are half-serious, but there are evidences of tipping points

Hello Odograph,

Thxs for responding.  I have no doubts that the world will gradually be driven to conserve, but I also surmise that yeast inside a wine bottle can gently swim away from their pollution or fellow yeasties to find new sugars until they are all hopelessly trapped.  I am enjoying the ice-cold, frosty results of a crashed ecosystem as I write.  

=D  Yea,baby!  I am getting pretty good at remembering to shout-out Peakoil when the long-neck is half-empty!

If a Foundation already exists, or can be created in time, can it prevent us from stupidly imitating the Yeast?  Can we optimize the Dieoff bottleneck?  Shouldn't all Peakniks encourage further Foundation controls?  Shouldn't we all be grateful that some ruthless dudes already Peak-shifted us by twenty years-->more time in the Bottle?

I have no idea what is the best answer to these questions.

Sip, Sip, Slurp, Guzzle--Peakoil!-- Guzzle, Slurp, Sip, Sip!

Bob Shaw in Phx,Az  Are Humans Smarter than Yeast?

>Second, I think decades are the correct timescale for energy transitions.  Projects take decades to come on-line, and reserves take decades to run their course.

I think he means that we no longer have decades left to make the transistion. Considering the production declines in Q1 2006 (down by 1.3%) its seems very unlikely that very much time remains. We are probably less than five years away from steep declines, and will take at least five or more years to build a new Nuke or coal plant.

> those projects are doing so that we can start any decade-long transitions we need to make.  You know, as stated in the Hersch report.

The issue is that alterative energy projects don't appear to scale very well. For example, the massive cost overruns in alberta tar sands project. The Hirsch report also neglected to discuss food production problems, what do when Green revolution (farming using petrochemicals) is no longer viable.

A steep downslope would be exciting, but I'm not sure a steep downslope for old resevoirs means the same for the total aggregate (including new fields).

A slow decline would give everyone time to adjust, including those farmers who would perhaps drop luxury crops and concentrate on sutainable practices for core calories.

... I think that if a stong numbers-based case could be made for a steep decline, soon, we'd see a lot more action out there in the world.

>A steep downslope would be exciting, but I'm not sure a steep downslope for old resevoirs means the same for the total aggregate (including new fields).

All of the newer fields are far smaller and therefor have very steep rises and declines. World production hinges on the production of the dozen largest fields.

>A slow decline would give everyone time to adjust, including those farmers who would perhaps drop luxury crops and concentrate on sutainable practices for core calories.

To move to a sustainable system without fossil inputs, farmers will need to use 8 to 10 times the current land to produce the same amount of crops, or reduce crop yields to between 1/8 and 1/10 of current production. Considering that there is already a water shortage, I can't see them expanding farm land very much. We are already producing less crops because of the high fertializer costs.

>I think that if a stong numbers-based case could be made for a steep decline, soon, we'd see a lot more action out there in the world.

Yeah, When this happens, Oil and Gas Exporters cut back or end exports to preserve thier remaining reserves and the importers switch to Panic mode.

All of the newer fields are far smaller and therefor have very steep rises and declines. World production hinges on the production of the dozen largest fields.

I (as a consumer, not creator) of plots, have been reassured by TOD's own Stuart Staniford when he says "Hubbert Theory says Peak is Slow Squeeze."

http://www.theoildrum.com/story/2005/12/5/133418/045

Maybe that's the place to ground this discussion.  Before we talk about argiculture "without fossil inputs" let's see the oil depletion curve.

>I (as a consumer, not creator) of plots, have been reassured by TOD's own Stuart Staniford when he says "Hubbert Theory says Peak is Slow Squeeze."

While Stuart in indeed a very bright and analytical fellow his analysis is flawed. For instance the data model he is using is based on HL for Texas production, which peaked without the use of advance Oil recovery technology. The dozen of the largest fields, have all peaked more than a decade ago, but used Advanced Oil Recovery to sustain production, while new production was developed using smaller fields. But doing this the production curve of these fields no longer follows the standard bell curve. Instead it shaped more like a fliped Chi-Square curve, where the decline in the future is much steeper than the traditional bell curb.

Another words, we have applied stimulus to the field (using water injection) to force production to remain stable for a much extended and ultimate altering the production curve. Because of this, we can not rely on the HL to accurately map out future production.

DuncanK has done better analysis showing a more probably HL curve by accounting for Advanced Oil Recovery.

http://www.theoildrum.com/story/2006/7/7/13359/29714#26

As you can see, the future production curve is much steeper than Stuarts HL model.

A flipped (right to left) Chi-Squared curve most likely accurately measures histortic oil production. Back in 1860, oil discovery and production was primative. As we studied geology and developed better technology we were able steady increase production over time. However since there is a finite supply and limits to applying new technology it is very presumable that production will decline rapidly in the future.

We also must seriously consider future rationing by oil exporters which will compound the problem. If your an exporter and oil becomes a precious consumable commodity, do you continue business as usual and quickly deplete your remain reserves, or do you act to preserve it? If you only had one tank of gas left forever, would you use to go on one more vacation trip, drive your neighbor to visit thier relative, or do you conserve it for something much more important?

I did not see a "world" plot at that URL.  That's the crux.
>I did not see a "world" plot at that URL.  That's the crux.

If you smell smoke there is bound to be a fire somewhere. We can't construct an accurate world plot because the majority of the worlds major exporters have choosen to hide their data (which in my opinion is hiding the truth). The HL plot data comes from exports, and doesn't reflect the state of remaining reserves. If we consider the rapid production declines from the North Sea and Yibal that used Advanced Oil Recovery, we should also consider similar results from other fields that used AOR.

We Also have leaked reports of Cantarell and Ghawar, which tell us that the remaining oil columns are very small and shrinking fast. If these fields are about to be exhausted global production will fall by about eight percent, and thats from just two fields. We should consider that the other ten largest fields probably have simialar issues.

To be honest, I am convinced by people like Stuart because they do the numbers first, and then leave us to establish our level of concern.

To do "worry first" and "get the numbers later" doesn't work for me.

Very large parts of the South were once farmland (much up till ~1950) and now grow pine trees.  Much of East Texas, Mississippi, Alabama for example.

Land left fallow for a half century or more.  Pretty well exhausted when abandoned, but viable in some futures.

Wind has a short time lag.  12 months to expand existing wind farm; ~30 months for green field wind farm.  

Time measured from financial decision to production (pre-decision wind measurements, design, bids, licenses & permits, etc.).  However, large #s of sites are being evaluated world wide,

Magnus Redin -

I can see the advantages of going to a 72V auto electrical system, which are pretty much the same advantages that prompted the change from the 6V system on old cars to the 12V system that is standard today.

However, I am curious as to what kind of a storage battery you would have to use with a 72V system.  A lead-acid battery produces approx 2 volts per cell, which is why a 12V battery has 6 cells. So, if you stuck with a conventional lead-acid battery, would you not have to have 36 cells? if so, then to keep the same weight battery, you would have to reduce the size of each cell by a factor of 6.  This strikes me as bit unweildy.

I suppose you could stick with a 12V system if you had a transformer in the charging circuit, but that introduces an additional complication, some energy losses, and probably a bunch of other problems. Also, a 72V system would increase the severity of electrical shocks when servicing the car, but that is secondary.

Maybe a different type of battery would be better for a 72V system?

GM was talking about a 24 V system a few years ago.  Battery limitations were a factor in that choice.  Higher voltage than 24 V DC > more cells and thicker insulation.

Also the hazards from "jump starting" a dead battery car go up with voltage (the US electrical code is much more safety minded than the EU, thus 120 V).

My biological memory system kept saying 72V is not the right number.

Finally, I overcame laziness and looked it up: it's 42 Volts

The reason has to do with increased delivery of power at lower amperage P=IV =(I^2)R. By reducing current, you reduce heat loss as the square of the current.

The insulation of 12v systems is more than enough for 42v use. 42v is viewed as a logical voltage because that's the voltage of electric hi-los. The battery, controller, and motor production lines already exist and can be duplicated without big engineering costs.
In N. Minn. where temps can dip below minus forty degrees (where Celsius = Farenheit), people sometimes keep their batteries warm in their cars or trucks by making a little itty bitty teeny tiny short circuit that even in a week hardly drains the battery at all.

And of course, we use block heaters for the engines.

Pilots like to heat the oil to maybe 150 C. and then pour it into the empty engine to make it easy to start aircraft.

Siberians also have a lot of neat tricks to deal with cold weather.

Sometimes I dump some kerosine into #1 diesel to thin it out.

IIRC it was for the reasons stated, but 42V. As voltage increases, it becomes more hazardous - so as you get into the 48 or 50V range, you get into real regulatory hassles that increase size and weight of wiring and connectors considerably. I think they picked 42V to stay relatively clear of that. Since each car seems to have more wiring than its predecessor, it's an issue that can't be ignored.

The hybrid and EV motor batteries are a separate issue since no one in their right mind would distribute the full voltage of the big battery all over the car to power accessories. High voltage wiring is fine in the benign envronment of a building. But it's a problem in vehicular environments, which are subject to rain, icing, extreme temperatures, and, on occasion, sudden disassembly.