The UK government has rejected price support for Tidal Lagoon Power's (TLP) proposed 320MW Swansea Bay project.
BEIS Secretary Greg Clark told Parliament the scheme represents poor value for money for UK consumers.
“The inescapable conclusion of an extensive analysis is that however novel and appealing the proposal, the cost that would be incurred by consumers and taxpayers would be so much higher than alternative sources of low carbon power that it would be irresponsible to enter into a contract with the provider,” he said.
Clark said the lagoon failed to meet the government’s so-called triple test for support: maximum carbon emission reduction, a clear cost reduction pathway and potential for the UK to be a world leader in a sizeable global market.
The Swansea pilot would create only 28 jobs, he added.
TLP had sought an at least 35-year Contract for Difference from BEIS plus an £200m equity and/or loan investment by the Welsh government.
Trade body RenewableUK expressed disappointment with the decision not to proceed with the project.
“This decision shows a lack of vision,” said chief executive Hugh McNeal.
“We know that with the right support, tidal energy can quickly become competitive on cost with other renewable and low carbon power like nuclear.”
The so-called pathfinder project was backed last year in former energy minister Charles Hendry’s independent review into tidal lagoons commissioned by the UK government.
The project has yet to secure a seabed licence from The Crown Estate or a marine licence from Natural Resources Wales.
Scottish Renewables senior policy manager Hannah Smith said the UK maintains a world lead in developing wave and tidal energy.
"We would strongly encourage both the Scottish and UK governments to continue working with industry in order to determine the best way for our wave and tidal sectors to reach their full potential.”
Ocean Energy Europe chief executive Rémi Gruet said the decision to reject the project was “regrettable”.
“The UK government should now make sure it doesn’t miss out on other emerging technologies such as tidal stream or wave energy,” he added.
Image: Swansea Bay tidal lagoon (TLP)