Why hydroelectric sources are not used much in UK?

Hydroelectric sources are actually used quite extensively in the UK. In fact, the UK is the third largest producer of hydroelectric power in Europe. The main reason that hydroelectric sources are not used more in the UK is that the country does not have a lot of mountainous areas. This means that there are not many places where hydroelectric dams can be built. Additionally, the UK's rivers are often quite small and shallow, which makes them unsuitable for hydroelectric power generation.