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Nuclear fusion still an energy option
National Academy of Sciences publishes report recommending continued US involvement in ITER plus new research into the technology
Alan Bailey Petroleum News
The use of nuclear fusion, as distinct from nuclear fission, to generate electricity has long been a holy grail of energy research, always thought to be perhaps decades from achievement but never actually attained. However, a new committee report, published by the National Academy of Sciences, has said that enormous progress has actually been made towards achieving the generation of nuclear fusion power. The report urges the United States not to pull out of an international nuclear fusion project being conducted in France and called the International Thermonuclear Experimental Reactor, or ITER. The report also recommends that the United States should conduct its own research, based on a more scaled down version of the ITER technology.
Combine small atoms While nuclear fission involves the release of energy through the splitting of large atoms, nuclear fusion involves energy release from the fusion of small atoms to form larger atoms. The nuclear fusion process powers the sun and is also the basis of the power behind a hydrogen bomb. But the fusion process requires extremely high temperatures. While those temperatures in a hydrogen bomb come from a nuclear explosion, nuclear fusion power generation would require a much more controlled and sustained process - hence the technical challenge.
But the specter of nuclear fusion power is very enticing. The process would involve the fusion of heavy hydrogen, a common component of seawater, to form helium, an inert gas. And unlike nuclear fission, nuclear fusion would produce no radioactive waste.
Two techniques have been investigated for achieving a sustained nuclear fusion reaction. One technique involves the use of extremely hot plasma, referred to as “burning plasma,” confined within a magnetic field. The other technique involves firing a high intensity laser beam at fuel pellets. Both techniques need to cross the hurdle of continuously outputting more energy than is being put in, to make the fusion process happen. The new report addresses the burning plasma option.
“We are seeing tremendous progress being made in the path to achieving fusion energy around the world,” said Michael Mauel, professor of applied physics at Columbia University and co-chair of the committee that authored the new report. “Now is the right time for the U.S. to benefit from the investments in burning plasma research and take leadership in fusion energy.”
The benefits of partnership The committee found that, as a partner in ITER, the United States gains the benefit of the technologies developed in the project while only paying a fraction of the total cost of the research. For the United States to continue its own nuclear fusion research without ITER participation would cost the country more in the long run, the committee said.
“ITER plays a central role in U.S. burning plasma research activities and is the only existing project that is expected to create and study a burning plasma. It is the next critical step in the development of fusion energy,” the committee found.
US research However, the committee also found that the United States could also develop its own burning plasma facility, using the same technology as ITER but producing a similar power output from a smaller device, with superconducting magnets constraining the fusion plasma.
The new report suggests that the continued U.S. involvement in ITER and the parallel U.S. research program would require additional funding of $200 million annually for several decades.
Priorities for a U.S. nuclear fusion program should be increasing the power density in a fusion power system; learning how to handle heat escaping from the plasma; developing high-field superconducting magnets; and developing materials and technologies for extracting heat from the system and recirculating the heavy hydrogen fuel, the committee said.
According to the ITER website, construction of the ITER facility is well underway, with the first plasma generation anticipated in 2025. That would be followed by further construction, leading to the startup of the full scale, heavy hydrogen system in 2035.
Lockheed Martin project In 2014 aerospace company Lockheed Martin announced that it had assembled a team to develop and deploy a novel compact fusion reactor design within 10 years. Since then the company’s project has gone silent. However, there have been reports that in February of this year the company obtained a patent for its reactor design. It appears from the patent documentation and earlier statements made by the company that the device would use a plasma technique, but with a new approach to plasma containment. If successfully developed, the device could have the potential to power a ship or a large aircraft, with huge ranges, given the possibility of extracting massive amounts of energy from relatively small amounts of fuel. But the reality or otherwise of this nuclear fusion concept remains to be seen.
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