Electric Engine Efficiency?

In the September issue of MotorCyclist magazine author James Parker wrote an article about the TTXGP (world’s first zero-carbon motorcycle race).

The article discusses up and coming electric motorcycles and the recent race which featured all electric motorcycles. It’s not a bad article, but I take issue with one particular part of it.

In the article Parker knowledgably discusses engine efficiencies and compares the gasoline engine to the electric engine. He describes the Agni motor / engine as being between 65 and 90% efficient and the gasoline engine as only being 25% efficient.

He then goes on to equate the rough mpg the electric engine represents compared to the gasoline engine, but I’m a little bit lost at this point as I’m still hung up on engine efficiencies.

While I won’t dispute that an electric engine is more efficient than a gasoline engine I will point out that comparing the two, as is, sitting in a motorcycle or car is inappropriate. Why?

Well, I suppose the answer isn’t exactly a simple one. We, as a society, have been on the Global Warming Witch Hunt for years, now. People love to portray fossil fuels as evil incarnate so anything that represents a negative slant to fossil fuels is immediately propelled into the spotlight. What this does is alter our perceptions.

The perception from the article, from the government, from automobile manufacturers, etc., is that we should be using electric engines because they are cleaner and more efficient.

So the big question is, are they? Again, from a raw perspective – that is utilizing the energy available – electric engines are more efficient than gasoline engines. But if you are going to buy into the whole, or big picture, you must go beyond what is sitting in the garage.

If we take a traditional motorcycle, the fuel is stored in the bike in the form of a gas tank. It is then burned in the engine itself, and the result is energy. This energy then drives the engine and the wheel.
If we take an electric motorcycle, the fuel is actual stored somewhere else. It is also burned somewhere else, and the result is energy – which then has to be transmitted, and then stored again (in the form of a battery) before it can drive the engine and the wheel.

That’s a fundamental difference, because in the big picture we are accounting for how the energy is made or produced, but in the small picture it certainly appears that the electric motorcycle is a better choice.

So where does the electricity come from? Power plants. How is most of our power produced today? Easy – fossil fuels via coal or natural gas. Those plants have an efficiency of approximately 25% when they burn fuel. So the actual efficiency of the electric motorcycle isn’t any better (.8 x .25 = .20). And of course, you have loss of electricity over transmission lines and don’t forget the loss when charging the battery (about another 20%). And, we should take it one step further – burning coal (again most power plants are coal) produces more CO2 than gasoline. If you buy into the AGW hypothesis and you believe that CO2 is the breath of the anti-christ then the conclusion is that you aren’t getting any real environmental gain by using an electric motorcycle over a gasoline motorcycle.

Yes, there are windmills and solar panels, but they aren’t capable of producing enough electricity today. Nor are they as efficient over time as a coal or gas (BTW – nuclear would be the best choice!).

So that’s what I get irritated with. Not seeing the big picture and the press, and the people continuing to intentionally be misleading with information. Parker is an engineer – he should know better.