Note: This article contains one or more stocks with a market cap between $350 million and $2 billion. Such small-cap stocks tend to be volatile.
NEW YORK (TheStreet) -- It's time to settle the issue: are electric cars more efficient than gasoline powered cars? Not in terms of miles per gallon, as gallons only apply to liquid fuel, but in terms of miles per kilowatt hour, which applies to all forms of energy. In other words, can an electric vehicle squeeze out more miles per unit of energy than an internal combustion engine?
If not, then the entire EV industry is nothing more than a pipe dream funded by fantasy-driven environmentalists who just haven't done the math. But if so, then perhaps there is a real future for EV.
When considering this question, there are several key factors to take into account. First, there is the fact that you typically lose 90% of the energy when converting fossil fuel, in whatever form, to electricity. This means that powering a car by electricity produced by fossil fuel is about 10 times less efficient than powering a car directly by fossil fuel, all other things being equal.
Read More: 10 Stocks George Soros Is Buying
So on the face of it, electric cars are much less efficient in terms of miles per kWh. But there's a catch, and that is that all other things are not equal. Not only are they not equal, but they cannot be.
Why not? Because in order to harness the power of fossil fuel directly, an engine needs to be in constant rotation. Even in the case of a hybrid that idles in suspension, the entire engine and all of its connected parts, drive train, transmission, alternator, etc., needs to be rotating at around 2,000 revolutions per minute in order to get the car to move at a decent speed.
The process of rotating an engine and all its parts that fast all the time takes a lot of energy -- energy that does not need to be used in an electric car. With electric power there is no need for constant rotation at thousands of RPM of an entire apparatus at all times the car is in motion. That is the main reason electric cars are so quiet; they have very few moving parts.
So while converting fossil fuel to electricity is 10 times less efficient than using fossil fuel directly, all other things being equal, the efficiency of an electric engine over internal combustion may yet compensate for that.
An (almost) thorough answer comes from Tom Murphy of the University of California at San Diego physics department. According to Murphy, a 40 mile-per-gallon gasoline-powered sedan consumes 91.5 kWh per 100 miles. A Hummer, by comparison, eats 305 kWh per 100 mi, and a Toyota (TM) Prius hybrid about 73.
When we get into fully electric, the numbers improve even more. The best of them is Tesla (TSLA) , which goes 244 miles on 53 kWh, for a total of only 22kWh per 100 mi.
There are two more catches though.
82% of the electricity in the U.S. comes from fossil fuels -- oil, gas and coal -- and the efficiency of converting fossil fuels to electricity in the average power plant is about 35%, 90% of which makes it into your car through charging it. This brings the kWh/mi number for the Nissan (NSANY) Leaf, for example, from 33 back up to 130 kWh per 100 mi, or the equivalent of about 28 mpg.
Up next: efficiency numbers and the big news in EV.