[Peakoil] more on electric cars...

[Keith Thomas]

Very informative + lots of good questions towards the end.

Many thanks for the time, effort and thought you have put into this. It's worth bottling - but I'll save it to my hard drive instead.
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Keith Thomas
www.evfit.com
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On 07/04/2011, at 5:42 PM, Haudy Kazemi wrote:

On 4/6/2011 7:05 PM, Keith Thomas wrote:
> 
> Well, coal-fired power stations are also around 30% efficient:
> 
> http://www.euractiv.com/en/energy/analysis-efficiency-coal-fired-power-stations-evolution-prospects/article-154672
> 
> Take from this 30% the energy lost in transmission over the grid, and electric cars are already less efficient and more polluting than petrol cars are today.

When comparing transportation fueling systems, remember to account for energy losses at every stage.  Do a "wells to wheels" type comparison that includes all energy used in the extraction/mining/pumping/collection and refining of various energy sources.

Coal, for example, needs less processing before it is used in a coal power plant (which in some cases is located adjacent to the coal mine), while oil must be transported and refined into gasoline, diesel, and other fuels.

Nuclear power plants depend upon the mining and refining uranium both of which need significant amounts of energy.  The amount of energy used to mine nuclear fuels and amount of nuclear waste produced could both be significantly reduced if we reprocessed spent fuel (only about 1% of the uranium in a fuel rod is used before the fuel rod is considered to be used up), and used newer more advanced reactor designs (e.g. IFR).

When I last did a wells to wheels comparison on using oil/liquid fuels vs electric for transportation, I found that in the worst case the overall efficiency and overall pollution of coal generated electricity used for electric transportation was equal to that of oil.  In the average case (a mixed power grid), electric had an advantage.  In a hypothetical fully renewable power grid, electric wins.

A primary advantage of electricity is that it is a universal form of energy, meaning that you can readily generate electricity many different ways (e.g. hydro, nuclear, coal, liquid fuels, tidal, wind, solar, natural gas, etc.) whereas converting between those other forms (e.g. nuclear to liquid fuels) is difficult or highly inefficient or near impossible.  A grid originally powered only by coal can have other clean energy production systems added to it, gradually cleaning it up, with no need for the electrically powered equipment to be changed or converted.  Cleaning up dozens or hundreds of power plants can be easier than cleaning up millions of road vehicles.


With a bit of creativity, these different means of electricity production can be made to complement each other:
1.) hydroelectric/pumped storage can fill in during periods of low wind or clouds
2.) solar production peaks during the work day when power consumption is near the highest
3.) rooftop solar (with microinverters) produced power on-site where it can be used locally
(Note: this neatly bypasses issues of long distance transmission losses and capacity problems.  Most of the transmission energy losses take place during the peak power demands...this is due to Joule's Law and Ohm's Law...P=V*I and V=I*R ==> P=I*I*R .  On average, about 2% of the electricity produced at UK and 6.5% at US power plants is lost in transmission by the power grids.
http://tonto.eia.doe.gov/tools/faqs/faq.cfm?id=105&t=3
http://www.nationalgrid.com/NR/rdonlyres/4D65944B-DE42-4FF4-88DF-BC6A81EFA09B/26920/ElectricityTransmissionLossesReport1.pdf
http://www.nationalgrid.com/uk/sys_08/default.asp?action=mnch7_15.htm&Node=SYS&Snode=7_15&Exp=Y#system_Power_Losses

4.) natural gas turbines can provide additional peak power production capacity
5.) distributed electrical energy storage (made possible by widespread battery-electric vehicles) allows off-peak energy to be used on-peak (and done correctly would have minimal impact on the users, similar to how modern utility-controlled air conditioner power switches are only used for 15 minute intervals)
6.) coal and nuclear can also be used for baseload; some of these plants also support power scaling/load following
7.) existing power plants could be converted into combined heat-and-power facilities that produce electricity and hot water for district heating.  Heat at rural power plants could be used to heat greenhouses.
8.) national/continental grids with appropriate interconnects allow local/regional energy surpluses and deficits to be balanced out


The full impacts of any energy source should be considered, whether that is strip mining coal, pit mining uranium, or citing wind turbines away from bird flyways.  The magnitude of the impacts also should be considered...if our pet cats are killing 500-1000x as many birds as turbines, should we be so concerned about the impacts wind turbines are having?  Is the particulate matter released from coal power plants worse than the risk of a nuclear accident and contamination?  Should we be just as concerned about the radiation released continuously while burning coal in coal power plants as radiation released in a rare nuclear accident?  Even when the levels released are near to the natural background radiation levels?  Should we be concerned about the mercury released while burning coal to run an incandescent bulb vs using a CFL bulb?  Keeping things in perspective matters.


> The trick is to need to do less travel, not to hope for ways to continue travelling "business as usual".

Less travel can be part of the solution for some, even most people.  Less travel can mean eliminating completely random, wasteful, or non-combined trips.  Direct costs borne by the travelers are one way to encourage appropriate conservation.  Temporary price shocks do hold value in this regard as they bring attention to the issues at hand, get people thinking, and can serve as a early warning for later longer lasting price shocks.




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