Nukes play major role in SuperGrid concept

Nukes play major role in SuperGrid concept

Jun 14 - Power Engineering -

Congress is finally paying some attention to the president's proposed National Energy Plan. The usual characters have aligned themselves on the usual sides, promoting their favorite energy solutions and condemning the ones they dislike. Taking advantage of this opening to discuss our nation's long-term energy future, Dr. Chauncey Starr, president emeritus of EPRI, has proposed a comprehensive electricity generation and transmission system, but with a twist. Starr's farsighted proposal includes the use of nuclear generation and hydrogen fuel as integral parts of his scheme.

Starr has proposed what he calls a Continental SuperGrid. Starr's proposed SuperGrid is a coast-to-coast electricity transmission corridor of direct-current magnesium dibromide superconductors cooled by liquid hydrogen. Nuclear power plants spaced along the corridor would provide electricity and liquid hydrogen to the grid, and local branches off the corridor would deliver both electricity and gaseous hydrogen fuel in measured quantities along the way. This SuperGrid would supplement, not replace, the regional electric power grids now in place. Because of the scheme's long-distance transmission capability, the nation's electrical system could finally take advantage of the load diversity inherent in a country spread across four time zones.

The proposal has serious implications for both energy security and environmental quality concerns. Starr understands both nuclear power and our nation's desire for clean energy sources. His brilliant scheme recognizes the potential symbiosis between nuclear energy and hydrogen, and addresses the tough economic issues of the two technologies by making dual use of both. First, the hydrogen- cooled superconductors permit long-range electricity transmission without losses. Second, the diversity thus achieved, plus the coproduction of hydrogen, allows the nuclear plants to be run at peak efficiency 24 hours a day, seven days a week. If those plants are nuclear breeder reactors, their fuel supply is virtually unlimited, and they efficiently replace limited fossil fuels. Finally, the "spent" hydrogen, having performed its supercooling task, is collected and used as a transportation fuel.

The juxtaposition of hydrogen fuel and nuclear power potentially makes for strange bedfellows in support of this proposal. About 15 years ago, when I was in charge of research for a major utility, my company supported a project that attempted to find an economical way to produce hydrogen via photovoltaics. The talented electrochemist who directed this work was also good at working the research funding levers in Washington. For maximum success, he aligned himself with the advocates of renewable and "soft" energy, identifying hydrogen as a benign, populist energy resource. Making this connection put him in league with some of the most virulent anti-nuclear people in the country. In many of his technical papers and presentations, he opined that the hydrogen economy he envisioned could do away with nuclear power altogether. He expounded at great length on the inherent problems of nuclear power, but in so doing he mostly revealed his ignorance of nuclear technology. Unfortunately, some of his supporters thought the brilliant electrochemist also understood nuclear energy and accepted his nuclear criticisms without question. Now, as in the past, it seems that many hydrogen fuel advocates are still in the dark when it comes to a correct understanding of nuclear energy.

Nuclear advocates, on the other hand, realize that nuclear energy promises to be the most economical energy source for hydrogen production. It is still unclear whether or not any energy source can produce hydrogen cost-effectively, and the economics of most fuel sources shift over time. It seems reasonable, however, to use low- cost uranium fuel to produce two premium products: electricity and hydrogen.

Starr likens the magnitude of his proposal to building the Panama Canal, the Interstate Highway System or the first transcontinental railroad. Indeed, he observes that it would be logical to place the underground energy corridor in existing railroad rightsof-way. He also envisions construction of this energy backbone as a decades- long project. Like the railroads, Starr proposes to begin construction from both coasts, with the early benefits coming in the regions of most-costly energy. The SuperGrid will bring maximum benefits, however, only when it is truly connected coast-to-coast.

Starr regards the biggest hurdles as political, not technological. How does one keep the nation's priorities focused on this project for decades, without its getting derailed by other spending priorities? Even NASA, in spite of the natural appeal of space exploration, has had trouble sustaining long-term interest in its program.

Starr is under no illusions as to how difficult it will be to bring his vision to reality. There are significant institutional barriers. Who will take the lead and provide the coordination? Where will the funding come from? How can our country sustain such an expensive, long-range project? Starr recommends an independent agency, the Energy System Advanced Research Project Agency, to be modeled after the successful Defense Advanced Research Projects organization.

There are many barriers to making the Continental SuperGrid a reality. But the idea is worth pursuing.

BY JOHN C. ZINK, PH.D., P.E., CONTRIBUTING EDITOR