Source: NBCnew.com | Tom Metcalfe | December 29, 2017
Some experts think commercial fusion reactors could begin operation as soon as 2030.
Renewable energy sources like solar and wind account for a growing share of the world’s electric power. That’s no surprise, given concerns about the carbon emissions from fossil fuel-fired power plants and their harmful effect on the climate.
Nuclear energy offers some advantages over renewables, including the ability to make electricity when the sun doesn’t shine and the wind doesn’t blow. But today’s nuclear plants use fission, which splits atoms of rare metals like uranium. Fission creates radioactive waste and can be hard to control — as evidenced by reactor accidents like those at Three Mile Island, Chernobyl, and Fukushima.
Another form of nuclear energy known as fusion, which joins atoms of cheap and abundant hydrogen, can produce essentially limitless supplies of power without creating lots of radioactive waste.
Fusion has powered the sun for billions of years. Yet despite decades of effort, scientists and engineers have been unable to generate sustained nuclear fusion here on Earth. In fact, it’s long been joked that fusion is 50 years away, and will always be.
But now it looks as if the long wait for commercial fusion power may be coming to an end — and sooner than in half a century.
LEADING THE CHARGE
One of the brightest hopes for controlled nuclear fusion, the giant ITER reactor at Cadarache in southeastern France, is now on track to achieve nuclear fusion operation in the mid- to late-2040s, says Dr. William Madia, a former director of Oak Ridge National Laboratory who led an independent review of the ITER project in 2013.
Construction of the ITER reactor — a doughnut-shaped vacuum chamber known as a “tokamak” that spans more than 60 feet — recently passed the halfway point.
Madia says the decades needed to bring the ITER reactor to full operation reflect the huge engineering challenges still facing fusion researchers. These include building reactor walls that can withstand the intense heat of the fusion reaction — about 150 million degrees Celsius (270 million degrees Fahrenheit), or 10 times hotter than the core of the sun.
And then there’s the challenge of creating superconducting materials that can generate the powerful magnetic fields needed to hold the fusion reaction in place.