The ISS electrical system uses solar cells to directly convert sunlight to electricity. Large numbers of cells are assembled in arrays to produce high power levels. This method of harnessing solar power is called photovoltaics. The electrical system of the International Space Station is a critical part of the (ISS) as it allows the operation of essential, safe operation of the station, operation of. Since the station is often not in direct sunlight, it relies on rechargeable (initially ) to provide continuous power during the "eclipse" part of the (35 minutes of every 90 minute orbit). Each battery assembly,. From 2007 the Station-to-Shuttle Power Transfer System (SSPTS; pronounced spits) allowed a docked to make use of power provided by the. Use of this system reduced usage of a shuttle's on-board power. Each ISS solar array wing (often abbreviated "SAW") consists of two retractable "blankets" of solar cells with a mast between them. Each wing is the largest ever deployed in space, weighing over 2,400 pounds and using nearly 33,000 solar arrays,. The power management and distribution subsystem operates at a primary bus voltage set to Vmp, the of the solar arrays. As of 30 December 2005, Vmp was 160 volts DC (). It can change over time as the arrays degrade from ionizing. • • Solar panels need to have a lot of surface area that can be pointed towards the Sun as the spacecraft moves. More exposed surface area means more electricity can be converted from light energy from the Sun. Since spacecraft have to be small, this limits the amount of power that can be produced. All electrical circuits generate ; in addition, solar arrays act as optic.
