November 2007

Nuclear power is the answer

By Hans D. Baumann

Let's expose some of the myths about power that our darling environmentalists perpetuate.

Wind turbines: Here the myth is free energy. Wind turbines sell to municipalities by emphasizing that the operating cost is less than the cost per kilowatt-hour from fossil fuel fired power plants. This is generally true.

However, what usually goes unconsidered in the payback analysis is the high cost of capital. Part of the reason for this neglect is government subsides or tax breaks offset capital cost.

If one adds the real cost of capital invested plus interest expenses, then the comparison becomes negative.

The real joker is the fact that wind does not blow steadily. A wind turbine only operates 25% of the time at full load. Well, you might say, every time I drive past a wind turbine farm I see that the blades are spinning, even when there is little wind.

The reason is that large turbines feed their electric power directly into the power grid. That means they have to rotate at constant speed in order to maintain 60-cycle AC frequency.

Therefore, if there is no wind, then they use electricity from the grid in order to keep spinning.

Electric cars: Another trend is toward electric or battery-powered vehicles. I looked aghast at a photograph published in a local newspaper showing a car connecting to an electric power cord. The caption said, "Ford plugs energy savings."

This is, of course, a ridiculous statement. If anything, battery-operated cars use more energy than equivalent gasoline-powered vehicles. First, the electricity used to charge the batteries has to come from (usually) a fossil fuel using power plant spewing CO2 into the air.

Secondly, batteries have an efficiency of only about 80%. For each 1,000-watt input, you only get 800 watts back. There is another 10-20% loss of power in the electric motor and drive train.

Finally, an electric car is much heavier than an equal horse-powered conventional car due to the great weight of the batteries.

Therefore, instead of refining the oil into gasoline, we have to burn it in a power plant, and then transfer the electricity (at a loss) to our homes in order to charge the batteries. Finally, we have to convert it back into mechanical power through an electric motor.

Ethanol: The myth is we use ethanol to replace oil. The unfortunate reality is that here again, we have a case where we utilize lots of oil or other hydrocarbons to save a little oil (gasoline).

In order to grow corn, we have to use fertilizers (from hydrocarbons and natural gas), pesticides (from oil), agriculture machinery, and transportation (using oil and gasoline).

According to James Howard Kunstler (The Long Emergency), it takes the equivalent of 7 gallons of oil in order to produce 1-gallon oil worth of energy in corn. Ethanol is only competitive if the oil price stays above $50 per barrel.

Ethanol, like gasoline, contains carbon and produces CO2.

Hydrogen: Remember last year when all the pundits said, "Why not burn hydrogen in your car, the lakes are full of the stuff?" Well, it does not work that way since water is already "burnt hydrogen," and you cannot burn it twice.

In order to produce hydrogen, you have to separate the hydrogen from the oxygen atoms. This is electrolysis, a very energy-consuming process.

Roughly speaking, one uses three gallons of oil in order to produce the equivalent of 1-gallon of oil in hydrogen form. Well, you might say the car that runs on hydrogen does not produce CO2. Yes, but how about the CO2 that goes to heaven from the three gallons of oil (or gas) that burned up while producing the hydrogen?

Outlook: It certainly behooves us to conserve energy and to reduce our dependency on oil and natural gas. However, let's do this in a rational and efficient manner.

To believe scientists will somehow "invent" future fuel is wishful thinking only because it violates natural laws. The only rational alternative is either fission or fusion technologies.

Build nuclear power plants.

ABOUT THE AUTHOR

Dr. Hans D. Baumann, PE (hdbaumann@comcast.net) is an ISA member and a member of Sigma Xi. He has an industrial engineering education and a Ph.D. in mechanical engineering.