Is nuclear fusion the future? The race is heating up to bring star power down to Earth. But some scientists are sceptical this technology will ever be more than science fiction.
China’s artificial sun sets new world record
Starstruck: Large stars such as the one above produce huge amounts of energy. Glossary
Fossil fuels - Fuels made from decomposing plants and animals, including coal, natural gas and oil. These fuels release carbon dioxide, causing global warming.
Pipe dream - Something that will never happen - that a smoker might dream about while puffing on a pipe.
Chernobyl - The disaster, in 1986, involved a meltdown at a nuclear plant in Ukraine.