In fossil fuels powered power stations fossil fuels (such as coal) are burnt to generate heat. This heats is used to heat a large amount of water and turn it into steam. The movement of the steam causes turbines within the power station to turn. The turbines are connected to generators that, due to the rotating turbines, generate electricity.
Solar powered power station function in a similar way. The only key difference is that the heat used to turn the water into steam comes from solar panels that absorb sunlight. This is a more environmentally friendly approach than burning fossil fuels for 2 reasons. Firstly, burning fossil fuels releases greenhouse gases which contribute to global warming. Secondly, fossil fuels are finite and can eventually run out, wheras sunlight is a sustainable source.