Extending photovoltaic operation beyond 2000 suns using a liquid metal thermal interface with passive cooling

Photovoltaic systems operating at solar concentration levels in excess of 500 suns require efficient cooling systems to manage the associated high incident power densities above 50 W/cm2. We present results for a liquid metal thermal interface with a 2-5 mm2C/W thermal resistance used in conjunction with a 1 cm2 commercial triple junction concentrator cell to produce up to 75 W of electrical power. We show that the liquid metal interface can be used to extend the limits of passive cooling relative to polymer thermal interface materials for solar photovoltaic concentrator systems. We will discuss the operation of triple junction photovoltaic cells above the 2000 sun level employing the liquid metal thermal interface and passive cooling. © 2008 IEEE.