Station reel time : power systems (1998)

and now it's time for our feature presentation and action whenever you turn on the TV to watch your favorite program or turn on the light in your room so you can see do you think about where the electricity comes from that makes them work here on earth large generating plants create electric power and send it through power cables right to the electrical outlets in your house now that you know that think about where electricity would come from if you lived on a spaceship above the earth no electric cables there it's too far did you know that very soon the United States and several other countries will begin building a huge space station that will orbit Earth for more than 10 years teams of scientists and astronauts will live and work on the International Space Station and they're going to need electrical power just like you do at your house but how will they get it it will be generated too but in a different way than the electrical power you get the space station will be the largest structure ever put into space it will be 108 metres long longer than a football field and eighty eight metres wide and it will weigh more than half a million kilograms some of the largest parts of the space station will be eight giant solar panels and guess what these solar panels are going to collect energy from the Sun that will power the station it's going to work like this each solar array is made up of two identical blankets each 32 meters long and four and a half metres wide the solar arrays are covered with thousands of tiny cells made from silicon when these cells are hit by the sun's rays they generate small currents of electricity that's why they are called photovoltaic cells photo meaning light and voltaic meaning they produce electricity photovoltaic cells are not just used in space they're all around us on solar powered calculators toys at school crossings and lots of other places too together the eight solar panels on the space station will have more than two hundred and sixty-two thousand photovoltaic cells and they'll produce about 240 kilowatts of power that's about the same as 4,000 60 watt light bulbs so what are they going to do with all that power half of it will be used to charge the space stations batteries since the solar arrays get power from the Sun some has to be saved for those times when the station is not in position to get direct sunlight the other half of the power will go directly to the laboratories and modules to run the systems that provide air to breathe and make the station livable it will be used also to cook and store food the electricity generated by the solar arrays helps to run the equipment in the space station laboratories where scientists will perform experiments it can't be done on earth and from these experiments we may get new medicines to cure diseases new and stronger building materials and scientific discoveries that may make life on Earth better in many ways and we'll prepare humans to explore the universe and just think it will all be made possible from the power we get from a star the Sun please join us again for station real time