The hybrid Chevy Volt is touted by General Motors as producing less carbon dioxide than purely gasoline-powered cars.  But that may not be true according to an analysis by Junkscience.com:

According to the EPA the 4-seat Volt is capable of driving 35 miles on its 16 kilowatt hours (kWh) of stored electric charge. The Volt’s gas-only fuel economy rating is 37 mpg.

Since two oxygen atoms from the atmosphere combine with each carbon atom when gasoline is burned, a gallon of gas produces about 19.6 lbs. of carbon dioxide (CO2) when burned. So when operating on gasoline, the Volt produces 0.53 lbs. of CO2 per mile (19.6 lbs. of CO2 per gallon divided by 37 miles per gallon).

Since we can’t quantify accurately just how much transmission loss there is between electricity generation and charging points, we’ll assume an impossible 100 percent efficiency at the charger to work out the CO2 emissions for the Volt’s 16 kWh stored charge.

In 2007, national “average” CO2 emissions were 2.16 lbs per kWh from coal-fired generation and 1.01 lbs per kW for gas-fired generation. according to Power Systems Analysis. Given that 44.46 percent of electricity in the U.S. is coal-fired and 23.31 percent is gas-fired, on a national basis, then, the mean emission of CO2 per kWh is 1.2 lbs/kWh. (2.16 lbs/kWh x 0.4446 = 0.96 lbs/kWh from coal, plus 1.01 lbs/kWh x 0.2331 = 0.24 lbs/kWh from gas).

The Volt’s “emissions mileage” from its stored charge is then 16 kWh x 1.2 lbs/kWh divided by 35 MPG = 0.55 lb CO2/mile.

So on an “average” basis, the Volt emits more CO2 from battery use than from gasoline use (0.55 lbs/mile vs. 0.53 lbs/mile).

Maybe you don’t think that’s a big difference, but the difference becomes more pronounced when the Volt is charged in states that rely more on coal-fired electricity.

When I first read this analysis I wondered how one gallon of gasoline, which weighs about 6 pounds could produce almost 20 pounds of carbon dioxide.  Well according to a Department of Energy website, it works like this:

It seems impossible that a gallon of gasoline, which weighs about 6.3 pounds, could produce 20 pounds of carbon dioxide (CO2) when burned. However, most of the weight of the CO2 doesn’t come from the gasoline itself, but the oxygen in the air.

When gasoline burns, the carbon and hydrogen separate. The hydrogen combines with oxygen to form water (H2O), and carbon combines with oxygen to form carbon dioxide (CO2).

A carbon atom has a weight of 12, and each oxygen atom has a weight of 16, giving each single molecule of CO2 an atomic weight of 44 (12 from carbon and 32 from oxygen).

Therefore, to calculate the amount of CO2 produced from a gallon of gasoline, the weight of the carbon in the gasoline is multiplied by 44/12 or 3.7.

Since gasoline is about 87% carbon and 13% hydrogen by weight, the carbon in a gallon of gasoline weighs 5.5 pounds (6.3 lbs. x .87).

We can then multiply the weight of the carbon (5.5 pounds) by 3.7, which equals 20 pounds of CO2!

The 2011 Chevy Volt from Government Motors is touted as the answer to carbon emissions and green jobs. The Volt, a hybrid vehicle, is said to be able to go 40 miles on one battery charge. The 1911 Baker Electric from the Baker Motor Vehicle Company of Cleveland, Ohio, could go 50 miles on one battery charge. The 1902 Baker Torpedo set a land speed record.

Electric cars have been around since the 1830s. First developed in Holland, then France and Britain, electric cars were first produced in America during the 1890s.

The turn of the 20^th Century was a time of experimentation in transportation. For instance, in 1900, a total of 2,370 automobiles could be found in New York, Chicago and Boston. 800 of those cars were fully electric, 400 cars were powered by gasoline, and 1,170 were steam-powered automobiles.

The early electric vehicles, such as the 1902 Wood’s Phaeton, were little more than electrified horseless carriages and surreys. The Phaeton had a range of 18 miles, a top speed of 14 mph and cost $2,000. Later in 1916, Woods invented a hybrid car that had both an internal combustion engine and an electric motor.

Electric vehicles have always been the playthings of the well-to-do. Even the earliest models were expensive for their time. The 2008 Tesla Motors Darkstar Roadster has a net base price of US$101,500 and can go 200 miles on a battery charge. The Chevy Volt with its $41,000 price tag and 40-mile electric range, is also a plaything of the relatively wealthy. And if the government offers a $7,500 rebate, that just means the rest of us are subsidizing toys for the rich.

Advances in battery technology still have not found the solution to long range and quick recharge time. Purely electric vehicles may satisfy a niche market, but they are still impractical for general transportation. Hybrid vehicles, first developed in 1916, just make automobiles unnecessarily complex. It’s just physics. Gasoline has 80 times the energy density of the best lithium ion batteries.

The whole impetus behind electric or hybrid vehicles is they will lower our carbon footprint. But will they really do that?

According to the US Department of Energy, most electricity generation in the United States is from fossil sources, and half of that is from coal. Coal is more carbon-intensive than oil. Overall average efficiency from US power plants (33% efficient) to point of use (transmission loss 9.5%) is 30%. Accepting a 70% to 80% efficiency for the electric vehicle gives a figure of only around 20% overall efficiency when recharged from fossil fuels. That is comparable to the efficiency of an internal combustion engine running at variable load. The efficiency of a gasoline engine is about 16%, and 20% for a diesel engine.

Because of the relatively high price of electric/hybrid vehicles, German automakers say, Without government subsidies, electric cars are virtually unmarketable. If all that is true, we are spending much money on a fantasy. But, the electric car “has long been recognized as the ideal solution” because it “is cleaner and quieter” and “much more economical.” That statement was published by The New York Times on November 12, 1911. We have yet to see that rosy prediction come true, as noted by the Energy Tribune.