Electricity is usually made by turning magnets inside a coil of copper wire.
At present most electricity is made by burning fossil fuels like coal to boil water which makes steam which turn the turbine and the magnets and so electricity is produced. If we can turn the magnets without burning coal or even invent another way of producing electricity we can help lessen our greenhouse emissions.
There are a variety of methods of generating electricity. Using Coal, Water, Solar, Wind, Tidal, Biomass are all examples. And of course there are new ways being invented all the time. Why not have a look in more detail at some of these methods. The link below will take you to the Canadian Electricity Association. They have some really simple explanations and some cool videos.