By Tom Mander
Burning fossil fuels is still a hot topic—no surprises there. “Be carbon free by… Cut emissions by… Keep the temperature rise under…” The rhetoric, like the pollution, lingers. However, recent developments in physics research centres worldwide offer new solutions and new hopes. China and Germany have grabbed headlines over the last few months with groundbreaking results in nuclear fusion: a highly efficient and powerful form of energy production. Could this finally be the 21st century’s answer to Climate Change?
In December 2015, Germany announced that it had maintained a cloud of hydrogen plasma (very hot, ionized gas) for around 0.25 seconds. It’s difficult to believe that such a brief period is so significant for the future of energy production, but it has catapulted nuclear fusion into the race for an alternative to fossil fuels. Now, researchers at the Institute for Physical Science in Hefei, China, claim they have held a cloud at 50 million kelvin for 102 seconds. What do these numbers come down to, and what makes this source of energy so exciting?
Nuclear fusion is the process of combining atoms’ nuclei together at high temperature to form heavier elements and energy—a lot of energy. Compared to the energy released in burning coal, nuclear fusion’s results are gargantuan and this is what makes it so appealing to a population which is expected to reach 9.6 billion by 2050. The main setback is providing the massive initial burst of energy required to initiate a fusion reaction. This is how the Sun makes energy, so nothing short of stellar temperatures are needed. Once started, however, nuclear fusion can become self-sustaining.
Be aware, this isn’t what happens in nuclear power stations already; that’s nuclear fission. Fission works by breaking down heavy elements into smaller elements and energy, but it produces nuclear waste which is dangerous to handle and expensive to deal with. Germany is currently passing laws to dispose of waste left behind from fission, which has become a controversial topic in German politics. Maybe this is why they are captivated by the glamorous Cinderella of nuclear energy and not its ugly step-sister.
And what does the future hold after the clock strikes midnight? ITER (International Thermonuclear Experimental Reactor) are the international conglomerate spearheading this development and they are not afraid to tackle the problem head on. Massive funding into more nuclear reactors —most notably Cadarache, a 15 billion euro research facility in Provence, France— indicate that this could be a profitable venture. With ITER spread from Kyoto to California in seven countries and significant backing from the EU, there is no doubt that it is being taken seriously.
Perhaps surprisingly, this technology has been around since the 1950s. An enormous torus with a strong magnetic field, called a tokamak, is used to maintain the plasma: this was first achieved in the 1960s Soviet Union. The game hasn’t really changed, but the players are far further than they used to be. When ITER finish their tokamak it will be the largest ever made, able to create temperatures 10 times as hot as the Sun’s core.
As with all new advancements, the experimental stages can be slow and arduous, and fusion is no exception. Cadarache won’t switch on for another four years and fusion is not predicted until 2027. Moreover, China’s EAST (Experimental Advanced Superconducting Tokamak) in Hefei only made it to about half the expected temperature needed. Germany are even further behind experimenting with another device called a stellarator, which could hold plasma for five times longer than a tokamak. So far it is the realm of theory.
Fusion offers no immediate solutions. The promise of unlimited power harnessed to quench humanity’s thirst for energy is still a glow on the horizon, with many practical barriers to overcome. Nevertheless, the glow is growing and new results fuel the excitement felt by so many about the future of sustainable fusion. Maybe the most exciting part is, in an increasingly divided world, the way the collective international effort has come together to solve one of the planet’s plights.
Photograph: Wendelstein 7-X stellarator under construction in 2011, Max-Planck-Institut, Tino Schulz via Wikimedia Commons