Massachusetts Institute of Technology, 2007 - $20,000

This E-Team is developing an inexpensive solar generator for powering off-grid communities in the developing world. Unlike standard photovoltaic panels, which only produce electricity, the team's device meets the entire range of commercial and residential energy needs: heating, cooling, and electricity. Using common, inexpensive auto parts and plumbing supplies, the generator works by using sun-tracking parabolic mirrors to focus the sun's rays on a pipe containing liquid anti-freeze. The refrigerant is heated and vaporized through a heat exchanger, driving a turbine-alternator assembly to generate electricity. Wasted heat is captured by a condenser and used to heat water. Altogether, the system costs about $3,000 and produces enough energy to power an off-grid school, health clinic or community center in the developing world.