The promise of fusion seems to have inspired more science-fiction novels than it has real developments in renewable energy, but Steven Cowley has begun to upset that balance. As director of the Culham Fusion Science Center, he's collaborating with the UK Atomic Energy Authority and researchers on the France-based ITER fusion device on projects that may lead to cheap, nearly limitless carbon-free energy.

Fusion (the process by which lightweight atoms under pressure are fused to form heavier atoms, releasing energy) has long been the Holy Grail of renewable energy, but at the moment it only occurs in the cores of stars. Yet Cowley isn't too shy to proclaim that harnessing its power on an Earthly scale is now inevitable. At UCLA, he made observations on some of the most violent phenomena in the local universe -- solar flares, storms in the Earth's magnetosphere -- and now his research is coming directly into play as he plans devices that, theoretically, would contain 100-million-degree gas using powerful magnetic fields.