Nuclear Power and a Hydrogen Economy?
Back in 2003, George W. Bush proposed the Hydrogen Fuel Initiative, a multi-billion dollar federal effort to make hydrogen into a competitive fuel and create a hydrogen-fueled car, both by 2020.
Among the initiative’s elements is an effort to produce hydrogen by using nuclear reactors. But amid all the hype about hydrogen, today’s nuclear power technology has been overlooked, although it is proven and ready to provide much of our energy needs, with or without hydrogen.
Many consider hydrogen to be the ultimate in ecologically friendly fuels: “It reacts cleanly with oxygen to become water with energy, and it’s everywhere. If only we had a good affordable fuel cell.” Yes, hydrogen is everywhere, but it is everywhere as compounds. The compounds must be broken. To do this, as per the first and second laws of thermodynamics, more energy must go into the compounds than can be gotten out of the product. That hydrogen can be converted from water using electricity doesn’t change the fact that it is a bad trade.
Using fuel cells to drive electric cars is the most efficient way of getting energy from hydrogen to a motor. But this option is very expensive. We could affordably start driving our cars on hydrogen right now – it burns great in gasoline engines, just not quite as well as in a fuel cell. The hold-up is not the fuel cell, it’s generation cost and storage. From the storage perspective, battery-driven automobiles actually look better than hydrogen, but we are not seeing many of them either, because neither can compete with petroleum at today’s prices.
Gasoline, diesel, and to a far lesser degree, natural gas, rule the road because they are still the easiest energy. Petroleum will have to become very scarce before you can’t get more out of it than you put into it. What else can we dream of that is so energy dense and available? And while we are dreaming, what if this energy did not emit combustion products like CO2 or pollutants?
With nuclear power we meet that dream. Petroleum cannot even compare with nuclear in energy density and cleanliness. Unfortunately, the fear-mongering regarding nuclear is only exceeded by that for global warming. I am not disregarding safety, but there is an inherent hazard in all energetic things – so we mitigate the hazards and accept them, and nuclear should be no different. The cost of safely derived nuclear electricity is similar to that of other sources, because it needs only to be competitive.
Because of its intense energy density and real affordability, nuclear power should be used everywhere, but it is not, because nuclear reactors cannot be made small. Nuclear reactors are large in both power and size, and are capable of taking on our greatest demands, except for the small, but many, burdens of automobiles and trucks.
To extend nuclear to automobiles, we can generate electricity to charge batteries or generate hydrogen. These activities have failed to compete with petroleum at yesterday’s prices, but if we can make our reactor power cheaper and our hydrogen generation affordable, perhaps we can maintain our petroleum-based prosperity. If not, we can still look environmentally progressive by reducing CO2 emissions, without the utter destruction of our economy.
Increasing process temperature can increase efficiency of hydrogen generation, and nuclear fission can run hot without generation efficiency loss, so to eek out small efficiency gains on hydrogen generation, new very high temperature, high pressure reactor designs are being considered. Costly developments and high operating costs will be required to use these extreme condition reactors (if it is even possible). So what have we gained?
Considering future petroleum prices, we only need today’s nuclear technology to compete. Today’s answer is moderate-temperature nuclear power plants, charging affordable, current-generation batteries in hybrid electric cars or battery-only machines to supplement petroleum. Tomorrow’s answer will likely be systems that generate hydrogen, through moderate temperature electrolysis that could be powered by today’s reactors, to use as feedstock for creating synthetic fuel.
Someday in the future, hydrogen may become a primary fuel medium. In the meantime, we should be building as many reactors as we can afford.
Phillip B. West is an Idaho Falls, Idaho-based engineer who studies energy issues.