Editor’s Note: Don Lincoln is a senior scientist at the Fermi National Accelerator Laboratory. He is the author of several science books for general audiences, including the best-selling audio book “The Theory of Everything: The Quest to Explain All Reality.” He also produces a series of science education videos. Follow him on Facebook. The opinions expressed in this commentary are solely his. View more opinions on CNN.
On December 21, 2021, an artificial sun briefly flickered into existence underneath the English countryside. At the Culham Centre for Fusion Energy, located just south of Oxford, scientists used a device called the Joint European Torus to create a controlled nuclear fusion reaction for about five seconds, generating 59 million joules of energy, or nearly 12 megawatts of power.
This achievement shattered the earlier record set in 1997, when the same facility created 21.7 million joules in four seconds. This is exciting news in the world of nuclear physics – but also in the world of climate science. When nuclear fusion technology is developed into a commercial technology, it will revolutionize how energy is generated across the globe and have a significant impact on the world’s future climate.
An energy output of 59 million joules is an impressive number, but to give it some context, this is only enough to power a typical American house for about half a day. Thus, while this recent accomplishment will not immediately result in a new power plant, it is still a welcome development for a world that is both hungry for energy and increasingly concerned about the dangers associated with traditional power generation.
Since industrial times, the majority of the world’s energy has been generated by burning fossil fuels, which has increased the amount of carbon dioxide in the atmosphere by about 50% above pre-industrial levels. The increasing concentration of carbon dioxide in the atmosphere is changing the Earth’s climate, causing hotter temperatures, more extreme weather events and more severe droughts. If humanity does not find ample and reliable sources of energy that don’t use fossil fuels, the climate crisis will continue to worsen, with a significant impact on mankind.
Many people recognize the need to turn to green energy solutions, such as solar panels and wind turbines. However, as ecologically friendly as those energy sources are, nuclear power dwarfs the other options in terms of the sheer amount of energy it can generate. Nuclear energy has to be part of a green future.
Nuclear power consists of two distinct technologies. One is nuclear fission, which is how all commercial nuclear power is currently produced. Energy is released when atomic nuclei are broken apart. This approach, however, generates large amounts of radioactive waste – some of which will last for centuries. There also have been industrial accidents, like at Fukushima and Chernobyl which have released dangerous radioactivity into the environment.
In contrast, nuclear fusion creates energy by fusing atomic nuclei together. This process generates more energy than fission and far less radioactive waste. What’s more, industrial accidents leading to a significant release of radioactivity cannot happen with a power plant using fusion technology. Finally, the fuel for fusion reactors deuterium and tritium, which are forms of hydrogen, are readily found here on Earth. There’s only one problem – scientists do not yet know how to make a fusion power plant.
Fusion occurs when atomic nuclei, in this case from the deuterium or tritium fuel, are heated to very high temperatures. There are several promising ways to accomplish this, from using quickly varying magnetic fields to powerful lasers to heat the fuel. The basic idea is that more energy comes out from the fusion reaction than goes into causing it to happen. If more comes out than goes in, we can use that extra energy to power civilization.
However, it’s very hard to harness nuclear fusion. Without protection, the very high temperatures needed would damage the reactor in which the process takes place, so scientists use magnetic fields to contain the heated fuel. These magnetic fields are essentially force fields that protect the surrounding material. Unfortunately, the heated deuterium makes its own magnetic fields, which interfere with the force fields. The JET facility generated fusion in this way. The extreme heat and pressure generated by the reaction means this is likely to be the JET’s last hurrah. It is unlikely it will be used again.
But there is a promising replacement on the horizon: the International Thermonuclear Experimental Reactor, or ITER. It’s currently scheduled to begin testing in 2025, although that date should be viewed with some caution, as the schedule has slipped in the past. Conservative estimates suggest that a 2031 startup date is more likely. ITER is designed to generate 500 million watts of power, with only 50 million watts used to heat up the fuel to get the fusion process started. Generating 10 times more power than one puts in is an impressive goal.
It’s also a misleading one. The 50 million watts is only the power supplied directly to the deuterium and tritium fuel. It doesn’t include the energy needed to power the magnets and the rest of the reactor. When those are taken into account, the ITER reactor will generate less energy than is needed to operate it. However, if it works, it will be a significant improvement over current facilities – a big step in the right direction – and there is no disputing that once fusion technology is mastered that it will be the energy technology of the future. Near limitless power, little waste and plentiful fuel are all very attractive attributes.
Of course, the question on everyone’s minds is, how long it will take for a working fusion reactor to be built that will produce more energy than it takes to operate? That is a very tricky question to answer. Since the first thoughts about harnessing fusion were bandied about in the scientific community in the mid-20th century, it was thought to be possible in about 20 to 30 years. But the estimate today is that it is still 20 to 30 years away. Given the reality of climate change and the fact that the energy needs of the future will certainly be greater than that of the present, this is a problem we have to solve. Additional investment in fusion technology research would certainly speed up the process.
Since the mid-1990s, American funding for fusion research has been roughly half a billion dollars a year, inflation adjusted to 2020 dollars. This sounds like a lot of money, but it should be contrasted with direct governmental subsidies for fossil fuels of $20.5 billion per year, with some estimates for annual indirect subsidies reaching as much as $649 billion. Given the effects of climate change, revisiting the nation’s budget for fusion research would be a good investment for the future. We owe it to our children.
Source: www.cnn.com