The supply of electricity from solar and wind power fluctuates, depending on the amount of sunshine and wind. The demand for electricity in an average household however, is always high as people like to do things at the same time, such as watching TV, boiling a kettle or charging a mobile phone. If we were to rely on the supply of energy from renewable sources alone, we would not be able to meet the demand. Nuclear power stations are essential as they generate electricity 24/7 and can provide a reliable source of energy to meet the world's increasing demand for electricity.