Further steps towards nuclear fusion?

The practical use of the technique for power generation has yet to be demonstrated, but research continues on several fronts

Alan Bailey

Petroleum News

Thought by some as the holy grail of eventual clean energy production, nuclear fusion has yet to prove its worth as a feasible means of generating electricity. But, with the possibility of generating power using heavy hydrogen from seawater, with no radioactive products or other contaminant emissions, a couple of announcements in recent months indicate continuing interest in this challenging avenue of research.

In October security and aerospace company Lockheed Martin announced that it has assembled a team to develop and deploy a novel compact fusion reactor design within 10 years, with a prototype potentially being available in five years after a series of design-build-test cycles.

“Our compact fusion concept combines several alternative magnetic confinement approaches, taking the best parts of each, and offers a 90 percent size reduction over previous concepts,” said Tom McGuire, compact fusion lead for the research team tasked with the new initiative. “The smaller size will allow us to design, build and test the CFR in less than a year.”

Also in October the European Union announced major funding for continuing nuclear fusion research by a variety of institutions in Europe. Of prime interest in Europe is ITER, a large fusion reactor being built in the south of Frances with international funding, including funding from China, India and the United States.

Unlike nuclear fission which releases energy from the breaking apart of heavy atoms such as uranium, nuclear fusion depends on the fusion of light atoms such as hydrogen. The fusion process, which powers the sun, depends on exceptionally high temperatures. A hydrogen bomb, for example, uses a short but very powerful nuclear fusion reaction, triggered by the immense heat from a nuclear fission explosion.

The technical challenge that experiments such as ITER are trying to overcome, to obtain an energy stream for power generation, is the need for the reaction to be self-sustaining by continuously producing more energy than has to be pumped in to cause the reaction to take place.

In 2013 a team based in the Lawrence Livermore National Laboratory in California announced some success with a nuclear fusion technique involving the use of the world’s most powerful laser to bombard a fuel pellet containing hydrogen atoms. However, it appears that this approach has yet to reach the point of achieving sustainability.