What are the disadvantages of hydroelectric energy?
disrupts habitats
flooding
lack of sites
political conflict
may produce hazardous materials
sites may stop producing energy

The disadvantages of hydroelectric energy would be the disruption of habitats, flooding, lack of sites and that sites may stop producing energy. The most common type of hydroelectric power plant uses a dam on a river to store water in a reservoir. Water released from the reservoir flows through a turbine, spinning it, which in turn activates a generator to produce electricity.

South wales composes a lot of coal in that region.

Dall of the above all of the choices make sense