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Jim Bullis, Miastrada Company

It is not specious to state the physics of energy conversion, where the existence of electricity depends on operation of a heat engine. There is always a combination of a heat engine and electricity if there is to be electricity. It is usual practice in physics to refer to the basic source as the fuel.

Rather it is specious to assert repeatedly that electricity is a fuel like other fuels. It is analogous to a drive shaft that carries energy from a transmission to a differential in a car. Would that make a drive shaft a fuel?

Renaming electricity as a fuel denies the fundamental law that energy conversion is far from a reversible process, that is, you can not get back the heat produced by burning fuel in a heat engine -- not even close. The heat that a kWhr of electricity can produce is a fraction (a tenth to half depending on the heat engine) of the heat required to make that electricity.

Ignoring the heat engine in measuring mpg causes a materially false and misleading statement. The fact that mpg is the only number most people understand shows how such statements will lead to seriously wrong decisions.

We already see that at least two of the plug-in car folks have tricked the DOE into thinking they deserve grants in the range of half a billion dollars.

Jim Bullis, Miastrada Company

You are right about the displacing petroleum part. If Energy Secy. Chu had stopped with that in his announcement things would be at least not misrepresented. However he went on to note the CO2 benefit in his announcement:
“Plug-in hybrid electric vehicles could revolutionize personal transportation and cut our dependence on foreign oil, not to mention give us cleaner air and less carbon pollution.”

Jim Takchess

What is the next step of Progressive Auto Xprize? What is going on now for the teams?

Jim Bullis, Miastrada Co.


In another discussion when I was looking up entropy in my handy old freshman physics book by Sears (Addison Wesley 1950), I found I was reading about the Second Law of Thermodynamics which Sears says “is the law of entropy.” Sears candidly says, “There is no concept in the whole field of physics which is more difficult to understand than is the concept of entropy, nor is there one which is more fundamental.”

I thus concluded that getting the concept of entropy thoroughly digested on these comment pages was unlikely.

However, now that I have the book open I note Sears also says regarding First and Second Laws of Thermodynamics, ” –every process that takes place in Nature,— must proceed in conformity with these two laws.” I rely on this to assert that wind and solar power are under this legal jurisdiction, contrary to some assertions. (Nature of course includes an important source like the sun which I will allow that we on earth can count as free of charge.)

That being said, I leafed back to the beginning of the chapter, p 436, to find an explicit statement in this, an established reference, that states that “chemical energy can be converted directly to mechanical energy — in an electrolytic cell.” Of course moving electrons are a form of mechanical energy, but it is amazing how many think otherwise.

Thus, my frequent statement is validated that electrical energy is indeed a carrier of energy, like mechanical energy in form of a rotating drive shaft of a car is a carrier of energy. It most certainly is not a fuel that must be first made into heat and then converted to mechanical energy.

Lots of people have one or the other of Sears' many textbooks on the subject. So they can look up for themselves that treating electricity as a fuel is an invalid practice. This reality will continue to make the AXPrize a less valued activity than it might be.

Neil Blanchard

I think the major point that has to also be made is, that electricity *can* be gotten from any number of sources. Whereas petroleum and most other carbon energy sources is finite. Out with the old carbon and in with the renewable energy/short-cycled carbon!

Lets not get hung up on the word "fuel" -- I think that thinking of it as "energy" is better, anyway. It is energy efficiency we are after, and if it comes from renewable resources, then that should be an advantage.

If the electricity comes from renewable sources, then it almost doesn't matter if it is "wasted", does it?

I totally agree with the major tenets of this article, and I am glad that the X-Prize is doing things this way.

Sincerely, Neil

PS: what is the MPGe (equivalent rating) of electricity used in the X-Prize contest?

Patrick Maston

Mr. Bullis, you stated in your first comment that "There is always a combination of a heat engine and electricity if there is to be electricity." I disagree. Wind, solar, and hydro power all produce electricity without a heat engine. If the Xprize used Well-to-Wheels and the EVs were charged with any of the above sources, MPGe would be infinity because there is no well. What do you think the "fuel" is in that case? Sunlight? Wind? PV panels? Or electricity?

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