There are two main competitors to the new nuclear power station at Hinkley Point, according to two sustainable energy projects.

The first is the Swansea Bay ‘tidal lagoons’ scheme, which is currently awaiting ministerial approval. The £1billion project involves building a walled lagoon in Swansea Bay that would generate electricity on the ebb and flood of every tide through largely British-built turbines, across 14 hours a day for a predicted project lifetime of 120 years.

The scheme could be in place and in operation within 5 years – although to make it happen, it would require subsidy at a level comparable to offshore wide or new nuclear generation. It would also need millions of tonnes of concrete and aggregates from quarries across the UK, and would of course radically alter the local environment, particularly affecting sea life and wading birds.

The lagoon power is, clearly, not without ‘teething problems’, but the look pretty modest when compared to nuclear reactor designs which may or may not actually work, and of course storing all the toxic waster afterwards.

Should the lagoons prove effective, the project could quickly be added to, with a second lagoon planned in Cardiff, as well as a string of sites along the English and Welsh coasts.

The enterpeneur behind this scheme, mark Shorrock, claims that this lagoon power could provide 8% of UK energy needs, which is more than Hinkley Point, and would be the lowest long-term cost per megawatt of any energy source.

The other big contender is offshore wind farms. Herik Poulsen, who is chief executive of the French company Dong Energy, says that wind turbines can be built on time and on budget, and give the UK a reliable source of power if they were combined with output from new biomass or gas-fired plants.

“Could you build a national energy policy without nuclear? Yes you could … and if you needed to fill a (energy capacity) gap offshore, wind could be accelerated to fill such a gap,” he said.

Poulsen claims that the Brexit vote has not caused him to rethink Dong’s £5.1billion investment programme in the UK, which involves constructing three more windfarms on top of the eight already operating.

“We hope offshore wind will remain a key component in the future energy system and are optimistic about prospects under the new government,” he added.

Britain has a total of more than 5GW of offshore wind capacity, as well as almost 9GW of onshore wind, and new projects are coming on stream all the time. The new proposed Hinkley reactors would provide just 3.2GW.