It sounds like science fiction but we may soon be powering our homes with the same power as the stars. Fusion promises to solve global energy woes but how are scientists going to pull it off and with experiments run hotter than the Sun, is it even possible?
The Sun is heated by fusion – a process where the nuclei of two small atoms, such as hydrogen, fuse together into a larger one, such as helium. The aim of fusion research and development is to create conditions on earth which are sufficient to generate many fusion reactions which may be harnessed to produce large amounts of thermal and/or electrical power. As there are no long-lived hazardous by-products and a plentiful supply of almost universally accessible fuel, fusion power has the potential to produce virtually limitless amounts of power in an environmentally friendly and economically viable way.
Making fusion work on Earth is a challenge scientists are working to meet. “In the Sun, gravity holds it all together,” says John Howard, from the Australian National University. “We don’t have enough gravity on Earth. Instead we can build a magnetic thermos flask to hold it together.”
The Australian Plasma Fusion Research Facility was upgraded last month to better understand the physics of fusion. Based on a type of magnetic bottle known as a stellarator, the machine uses radio waves and microwaves to heat gas until it forms plasma hotter than the centre of the Sun. “The reason it has to be so hot is because there’s so little of it there. It’s just a puff of gas in that machine,” says John.
The technology could work, but we’re not plugging in yet. “There are still some big technical challenges before you have a machine that can release power steadily back to the grid,” says John. The next leap forward in fusion research is ITER – a huge international project with a massive machine being built in France. Its goal is to produce 500 megawatts of power.
With the power of stars inside, is fusion safe? All current nuclear power stations use another process called fission, which breaks large atoms into smaller parts. Scientists say that fusion is safer than fission and has no harmful by products like nuclear waste. “With fusion, there’s no chain reaction, it will never get out of control,” says John. “If you take the fuel away, it just stops.” Boyd Blackwell, who oversaw the upgrade of the Australian facility, agrees. “You’re talking about much smaller quantities and risk scenarios that are on a much less likely scale than fission,” says Boyd.
Want to learn more check out http://www.iter.org/
Stay Curious C.Costigan
