TCS Daily


Power for the Sun

By Lawrence Weitzman - February 20, 2003 12:00 AM

For the last four billion or so years the Sun has been producing energy from the simplest of elements, hydrogen. It is a powerful energy source and it is abundant here on Earth. But is it the answer to our growing energy needs? Some people believe so, and are pushing the U.S. to spend billions on research. President Bush now proposes to allocate $1.2 billion in federal funds for research in the development of "clean, hydrogen powered automobiles."

Hydrogen may be a good fuel for the Sun, but the human experience has been much less successful. Hydrogen was used in the early part of the 20th Century for buoyancy in lighter than air aircraft known a dirigibles. There were many accidents (in part due to the volatile and unstable nature of the gas), the most famous being the Hindenburg which caught fire and exploded on landing at Lakehurst, New Jersey on May 6, 1937 killing 36 people. That accident ended the use of hydrogen as the gas used to fly lighter than air aircraft, with the replacement gas being the twice as heavy, but inert element of helium.

Despite these setbacks, hydrogen enthusiasts are confident that it can be a replacement energy source for petroleum based gasoline. But to do so, it must overcome some substantial hurdles.

High Hurdles

First is the problem of manufacturing hydrogen. It is not abundant on Earth in its pure form, so it must be extracted from other compounds such as water. The process is called electrolysis whereby electricity is used to separate the hydrogen from the oxygen. It is a proven process, but an expensive one. And it takes more energy to manufacture it than the resultant hydrogen will produce. In short, the process is an energy deficit.

Second is the issue of where do you get the energy to power electrolysis? If it's from gas fired electrical plants, there is no "greenhouse" benefit due to substantially reduced greenhouse gas emissions. Since most of the hydroelectric power dams have been built (most locations have already been utilized), the only other clean source of electricity available is nuclear - and you know the resistance there will be to building more nuclear power plants.

Third, hydrogen is difficult to transport and handle. To create the density necessary for adequate energy, hydrogen must be cooled and liquefied to temperatures hundreds of degrees below zero. The cost of the infrastructure including the transportation system will be enormous - possibly prohibitive. Attendants at filling stations will have to be expert in handling hydrogen, and filling your car could be a hazardous event.

Despite all this, there are benefits for the use of hydrogen as a fuel. First it can be applied to the current internal combustion engine with small modifications. Since it has a much lower energy density than gasoline, engines will have to be much larger to obtain the performance levels we currently enjoy.

For example, BMW currently has a working V-12 that is hydrogen powered. This engine in gasoline form produces about 400 hp. With hydrogen, horsepower drops to just 160 hp and performance is at the level of a Toyota Corolla running on three of its four cylinders. BMW claims a 0-60 time of 10 seconds whereas the gasoline version will accomplish this performance parameter in about six seconds or less. Although this process will continue to produce CO2, other tail pipe emissions - the ones that cause dirty air or smog - would be eliminated.

Applying this technology to fuel cells may be a better application. But after you solve the problems of logistics and infrastructure, then you have the cost of fuel cells themselves. It is a technology that requires the use of expensive precious metals and meticulous, exacting manufacturing techniques. It remains to be seen whether mass produced fuel cells can be practical and inexpensive. If you believe they are a decade away, I have a bridge to sell you. More likely, commercially viable fuel cells are several scores of years from becoming a reality.

So why is the President spending billions on fuel cells and hydrogen fuel? Does he really believe it is the answer to our energy problems? Probably not. President Bush may be circumventing the spending of untold billions by demonstrating at this time the impracticality of fuel cells and hydrogen fuel while politically placating the environmental alarmists.
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