Safe, inexhaustible, zero-carbon energy is a dream for a truly sustainable planet. According to a team of Imperial College London physicists who have been showcasing the exploits of British plasma physics, this may well be an achievable dream in the next 50-100 years, with just a little inspiration from the Sun.
“The process that powers stars, and the Sun, is called nuclear fusion” says Dr Arthur Turrell from the Plasma Physics group at Imperial. Importantly these nuclear fusion reactions can produce huge amounts of energy, safely and with no carbon dioxide emissions. “Our research is trying to understand how this energy is transported from the centre of the Sun to the surface” adds Turrell.
Nuclear fusion produces energy as a result of two or more relatively light atoms joining together, a process called nucleosynthesis. This fusion of atoms to create a heavier nucleus is the process that powers all stars in the universe, including the Sun, “A single kilogram of fusion fuel used up in reactions releases the equivalent energy of a large wind turbine running for 11 years, or burning 50,000 barrels of oil” says Turrell. If this process could be recreated and the energy captured on Earth then a new abundant, high-powered, green energy may soon be available.
Clean energy and lasers
The cutting-edge research that was displayed at the Royal Society Summer Science Exhibition, involves bringing the power of the Sun to Earth for just a billionth of a second, “we’re on the verge of being able to recreate the conditions inside stars using high powered lasers” says Dr Turrell. The Orion laser used by the team “…uses a combination of long pulses and short pulses [of light] to generate powers within excess of the entire UK national grid” explains Colin Danson from the University of Oxford who was responsible for building Orion. From this, the processes that take place at the heart of the sun, including nuclear fusion, can then be investigated here on Earth.
The future of nuclear energy
Nuclear fusion provides a potential solution to the problems and worries over nuclear energy. Currently nuclear power stations are fuelled by nuclear fission; the ‘radioactive decay’ or splitting up of atoms. Whilst nuclear fission produces huge amounts of energy, there are concerns over the unstable nature of these fission reactions and the amount of radioactive waste that they produce. In contrast to this “fusion reactions are incredibly safe, and produce little radioactive waste” says Arthur Turrell. The radioactive waste produced by fusion reactions also loses its ‘radioactivity’ a lot faster, meaning it is hazardous for a much shorter time period. Fusion reactions may therefore provide a more viable long-term solution to sustainable energy and reduce worries over the safety of nuclear power.
If the team are successful Arthur Turrell claims that “mimicking the processes that power the Sun would transform our energy supply”. Currently strains of research are focussing on how the energy released from fusion reactions can be efficiently harnessed and transferred into energy for everyday use, something the team believe can be achieved in tens as opposed to hundreds of years. Seemingly the driving force of all life on Earth may therefore also hold the answers for the sustainable future of our planet.
This research was presented as a part of an exhibition showcased at the Royal Society’s Summer Science Exhibition held from 1-6 July. To find out more about the other exhibits shown, including how ants are helping to us to find new antibiotics and how we may soon be able to replace our own teeth, listen to this podcast from Quentin Cooper, presenter of Radio 4’s Material World as he explores the exhibition.