European scientists have announced they are one step closer towards making nuclear fusion a viable power source. An experiment at a site near Oxford, UK set a record for the amount of fusion energy produced, more than doubling the previous mark. Nuclear fusion comes from the fusing of two atoms at very high temperatures, which then releases a vast amount of energy. The energy produced in the latest experiment, for example, was enough to boil about 60 kettles of water. The progress emboldens the prospect of abundant energy without pollution, radioactive waste or greenhouse gases.