In conjunction with the Energy & Information Technologies Laboratory and the Laboratory for Manufacturing and Sustainability in Mechanical Engineering, our research aims to develop a Rankine cycle heat engine system which will convert sunlight to heat at 60-80% solar-thermal efficiency and electricity at 8-10% solar-electric efficiency using concentrating solar collectors. In contrast to photovoltaic systems which cost ~$7/Watt [Solarbuzz, 2007] of generator rated peak electrical output, in mass production the proposed collector and generator system sized at 1-10kW would cost ~$4/Watt electricity or $0.80/Watt heat, allowing adjustment of heat and electrical output on demand. Considering that 112 MW of grid-connected PV was installed in the U.S. in 2006, there is a large proven market for solar energy. With widespread market penetration, this system would reduce greenhouse gas and criteria pollutant emissions from electricity generation and heating for a significant portion of the developed and developing world.