On PopSci.com this week was a feature on ITER's hot fusion reaction experiment. The project, which is an international effort of scientists and engineers from the U.S., Russia, China, Korea, Japan, and the European Union, in the works for decades, but wasn't officially underway until November 2006, when the ITER agreement between the constituent nations was signed in Paris. Since then these nations have worked together with the understanding that energy demands will skyrocket in the coming decades and that our current means of energy production will be insufficient. According to the ITER website, energy demands are projected to triple by the end of the century, yet as fossil fuel costs continue to rise despite global recession and companies are forced to adopt dirtier methods of extraction it has become clear that fossil fuels are dwindling. The ITER Team, and its constituent nations, have decided that fusion is the answer.
Despite the well-known and well-publicized failures of cold fusion, hot fusion remains a very real and practical option for clean and copious energy. The fusion reaction take place in a donut-shaped containment apparatus called a tokamak. The tokamak holds two radioactive isotopes of hydrogen (deuterium and tritiem) which are held in place by magnetic fields. These isotopes are bombarded with particle beams and microwaves until they reach a temperature of 270 million degrees F, at which point the nuclei of both fuse (hence the name fusion). The heat from this future is captured by turbines which create electricity. The ITER reactor will be the largest tokamak ever built, creating 500 mW of power, roughly equal to that of a coal plant. Of course, it's drastically reduces greenhouse emissions, poses no threat of meltdown or significant radiation pollution, and it's byproduct is Helium...not radioactive waste. The reactor is scheduled to go online in France in 2019. Depending on its success the team may go on to build a much larger reactor by 2040, but first they need to make hot fusion economically viable.
Although it takes only 35-thousands of an ounce of tritium and deuterium to make the equivalent energy of 2,000 gallons of oil, the isotopes do not occurr naturally in the environment. Thus, they need to be made, which can be expensive since they're not in high demand (though should fusion become the energy answer of the future, they soon will). Likewise with tritium, the isotope can be made fairly easily with neutrons form a traditional fission reaction, but there is not much demand and no apparatus for delivering them. Ultimately, a fusion reactor will need to produce its own hydrogen isotopes.
One of the more pressing concerns right now is that the actual tokamak endures incredible amounts of radiation and heat, which wear down internal parts that need to be replaced. However, because of the radioactive levels, scientists can not work inside the tokamak and must develop robots capable of replacing those parts, some of which weigh in excess of 10 tons.
Despite the obstacles, the ITER team has been impressive in the global outreach and campaign for support. They see this as an investment for all humankind, one of the few projects like it that has retained such a pristine, a-political image. I first heard about ITER at an assembly for the National Education Association, where they were promoting their project and providing teachers with classroom materials for educating students on ITER and hot fusion reactions. Clearly the organization has an eye on the future, and it isn't just toward developing fusion energy, but toward the future generations that will need it.