Roger Highfield — Newsweek — August 2014
Within the next 50 years, scientists will build a fusion power plant to harness the same processes that make the sun shine. The moment this star winks on, everything will change.
Of course, that’s also what Cold War scientists said half a century ago when, after the uncontrolled release of fusion energy in hydrogen bombs, they took an interest in the controlled release of fusion energy in reactors. The Cold War is long over, but the same promise keeps getting made today. The difference, though is that now a number of companies – many in the commercial sector – are working in a nuclear field that was once only the domain of superpowers.
A century ago, scientists gleaned the first insights into how stars, like our sun, convert hydrogen into helium by the process of fusion and, as a byproduct, release colossal amounts of energy. By the mid-1950s machines to fuse light elements were working in the Soviet Union, the United Kingdom, the United States, France, Germany and Japan.
The dream has always been of near limitless energy. While a 1,000 megawatt coal-fired power plant requires 2.7 million tons of coal per year, a fusion plant of the kind planned for the second half of this century will only require 250 kilos of fuel per year and present fewer radioactive waste problems than conventional nuclear reactors.
The basics are simple. Take two forms of hydrogen, typically deuterium and tritium, squash them together, and you get a helium atom and a subatomic particle called a neutron. The product of this reaction (called D-T fuel) is a fraction lighter than its atomic ingredients and by Einstein’s famous equation E=mc2 (energy released equals the lost mass multiplied by the speed of light squared), that minuscule loss of mass results in a colossal release of energy. Continue reading here….