Energy storage is the key to feeding more wind and solar power into the grid, but the question is how to get all that stored-up renewable energy to someone who can use it. The same goes for recovering waste heat from industrial operations. UK firm Sunamp has come up with a unique solution that involves scavenging heat from one place and transporting it on water to another place, with the help of a new phase-change material that can last for 40,000 cycles or more.