What will the power stations of the future be? The energy world was given a startling glimpse of one possibility this week when Professor Brian Cox said they were likely to be nuclear – nuclear fusion.

Nuclear fusion is the process which powers the sun and has long been considered a safer way of creating energy to nuclear fission, the chain reaction which fuels nuclear power plants as we know them today.

Fusion is appealing because there is little risk of the chain reaction getting out of control and causing a meltdown such as those seen at the Chernobyl and Fukushima disasters. Some believe it is a pipedream but others such as Prof Cox think it could be the answer to our energy needs by the end of the century.

Addressing audiences at the Energy Event at the Birmingham NEC, the British particle physicist and ex-D-ream keyboard player was asked what energy source he thought would power the world in 100 or 500 years. He replied: “I think it will be nuclear fusion without a shadow of a doubt.”

Prof Cox said researchers are well on their way towards developing a prototype commercial reactor, pointing to strides taken with plasma. One of the main requirements for achieving fusion is to heat plasma particles to scorching temperatures of as much as millions of degrees Celsius.

He explained: “The European fusion project (Iter) aims to have plasma in it and doing research on how that plasma works by 2019…it’s under construction now. Nobody I’ve spoken to on that project believes that there will be any show-stopping problems with it.

“It is essentially a commercial reactor design give or take, so by the mid-2020s we should have essentially a working prototype commercial reactor.”

He added: “The cost is all infrastructure cost, the fuel is free and effectively infinite. Unless there’s some engineering challenge we don’t know about then surely by the end of this century, fusion power stations should be delivering essentially unlimited energy, not free because it costs a lot to build the reactors.”