Plans for six lagoon tidal power plants have been unveiled in the UK, with the first already in planning stage in Swansea.
The lagoons will use the change in water levels with the incoming and outgoing tides to power underwater turbines and generate electricity.
The first lagoon is planned for Swansea, with others planned for Cardiff, Newport, Colwyn Bay, Bridgwater, and West Cumbria.
The Swansea scheme is expected to cost £1bn and produce energy for 155,000 homes, with prices needed to be subsidised by the public. However, once the first plant is built, the firm behind the plans, Tidal Lagoon Power, say that building and running each of the other plants would be much cheaper.
The firm plans to charge £168 per MWh for electricity from the Swansea plant, but £90-£95 per MWh for power from a more efficient second plant in Cardiff, a price which aligns with the cost per MWh of electricity generated by nuclear power plants.
For a combined investment of £30bn, the firm says that the six lagoons could produce 8% of the UK’s electricity needs, with each plant planned to last for 120 years.