We are finally getting close to achieving sustainable nuclear fusion.

Nuclear fusion could be the key to producing almost-unlimited energy with few byproducts other than saltwater, but researchers have long struggled to create a machine that could sustainably control such a powerful reaction. But that's changing. At the end of 2015, Germany switched on a massive nuclear fusion reactor that's since successfully been able to contain a scorching hot blob of hydrogen plasma . They're not the only ones, either, with South Korea and China both achieving record-breaking reactions in their own fusion machines. The UK has also switched on a revolutionary type of reactor that is now sustainably generating plasma within its core. In fact, MIT scientists predict that thanks to all these new advances, we should be able to get fusion energy on the grid by 2030 .