There Is Enough Wasted Electricity To Power All Cars In USA

I was confronted with a serious argument against Tesla cars (or electrically powered automobiles in general). It reads thusly: «If you replace all cars with Teslas the power grid will not be able to sustain the resulting tremendous surge of energy consumption». To me it sounds like a legit matter for a quick investigation, so here we go.

According to U.S. Energy Information Administration the upper estimate of the total light-duty vehicles energy consumption in USA is: 7.5*10^6 boe/day. Let us convert it to more humane measurement units. 1 boe — an energy equivalent of a barrel of oil — is 5861520 kJ. And as you probably know 1 day consists of 3600*24 seconds.

7.5*5861520 [GJ] / (3600*24) [s] < 509 GWt

The entire energy demand for all light-duty vehicles nationwide is guaranteed to be less than 509 Gwt (averaged annually).

This is what combustion powered cars demand, and, as we are hypothetically moving to another type of engine, we must take energy efficiency of the engines into account. The best possible combustion engine in the world is less effective than 20% — I am generous enough to assume that it is the efficiency of all actually running cars. Unfortunately I do not have real data on the efficiency of Tesla Motors's motors, so I am going to assume they are very bad electrical motors, as bad as 85% (which is really low for general purpose electrical motors). Thus, the replacement will lower the energy demand:

509 [GWt] * 0.2 / 0.85 < 120 GWt

120 GWt

Can the national electricity generation industry cope with this additional consumer? Let's do some comparison to get the idea of how big this number is. The U.S. metallurgy wasted heat amounts to 200 GWt. According to some serious ecologists (not greenpeace bullies) (sorry! I have lost the link) up to 64 GWt of this wasted power is in principle convertible to electricity. So far, the demand does not seem catastrophic — we already have a potential source of energy that covers the half of the demand.

According to the same gov's source of info, better presented by wikipedia United States generated 4095 TWt*h in the year 2012 (not the best performance year — we are keeping the pessimistic view on the electric cars). Taking in account that a year typically consists of 365*24 hours, let's convert it to GigaWatts:

4095 [TWt*h] / (365*24) [h] > 467 GWt

Thus, the total demand of all light-duty vehicles amounts roughly to 1/4 of the electric energy currently generated — that is far from a catastrophe! 25% increase in generation is easily achievable, but not necessary! There are some wasted energy within the electric generation industry.

19% of american electricity comes from nuclear power plants. 2/3 of this electricity share is now wasted — dumped as heat — because of the low demand periods. (you can not shut down the reactor simply because your consumers switched off the lights). Thus, we have some free electricity:

0.19 * 0.66 * 467 [GWt] > 58.5 GWt

Almost a half of all cars nationwide — if they go electric right now — could be powered by currently wasted electricity, and another half could be powered by the wasted energy if we bother converting it to electricity.

Not only it is possible to switch the light-duty transport to electricity entirely, it is DESIRABLE to do so, and the big amount of electricity the cars consume is actually an advantage from purely economical standpoint, all green bullshit aside. Because the accumulators those cars use could be charged during the periods of low demand, thus FLATTENING the demand dramatically. And ask other people if you don't trust me, there is no worse nightmare for the electric generation industry than drops in demand! Those power plant engineers will build statues of a man who dares to establish a replaceable accumulator infrastructure with the industrialized charging facilities adjacent to power plants.


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