If you’re a fan of wind power, check out this design for high altitude inflatable wind turbines. An MIT-born company called Altaeros is working on a Buoyant Airborne Turbine, potentially enabling low-cost electric power anywhere in the world, providing emergency power in the aftermath of natural disasters or even general purpose power in remote off-grid locations.
For energy storage, how about giant balloons filled with compressed air and stored deep underwater? Water pressure keeps the air compressed in an underwater CASE (compressed air energy storage) system, which might work extremely with in conjunction with offshore wind farms.
And MIT researchers have found a highly efficient way to convert solar energy into steam using a spongelike structure consisting of graphite flakes and carbon foam. The material converts 85% of the incoming solar energy into steam and works even at very low solar intensities. If the team can scale the technology, it may have very useful applications for desalination, hygiene systems, and sterilization, especially in low-grid or no-grid environments (which are often places that desperately need effective water and sterilization technologies).