http://www.usatoday.com/money/autos/2008-07-07-prius-solar-powered-air-conditioning_N.htm A quick gut-check of the numbers shows that 2 kW is impossible and 5 kW is just downright laughable. A high quality panel such as THIS one generates about 140 w/m^2 and costs $5.5 per watt. That means that to generate 2 kW, the Prius would need 14 m^2 of panel facing directly toward the sun. The Prius is a hatchback, with a total length and width of 4.4x1.72= 7.57 m^2. Nevermind that at $5.5 a watt for 2 kW, the panels alone would consume roughly half the cost of the car. I wonder who this unnamed source is?