Grid connection secured for huge 3.2GW Cardiff Tidal Lagoon project

Tidal Lagoon Power has secured the grid connection for a 3,240MW capacity tidal lagoon located between Cardiff and Newport. The project is expected to generate among the cheapest electricity of all new power stations in the UK. 

The developer is also awaiting permission for the development of another tidal lagoon power station in Swansea, which is planned to have a capacity of 320MW and cost £1.3 billion (US$1.7 billion).

Once completed, the Cardiff tidal lagoon project will have an estimated electricity output of 5.5TWh per year, which according to the company is enough electricity to supply every single household in Wales.

The projected Cardiff project comprises a 20.5km breakwater wall enclosing some 70 km² of the Severn Estuary and housing up to 108 tidal turbines within at least two powerhouses. These would handle flows of some 600 million cubic metres of water on each tidal cycle. The project holds an estimated investment of £8 billion (US$10.86 billion).

When operating in pumping mode, Cardiff Tidal Lagoon could act as a flexible load for the grid, with up to 2,171MW of demand permitted under the agreement with National Grid.  Crucially, this could be timed to facilitate the integration of more intermittent wind and solar power and more inflexible nuclear power into the future energy system.  A portfolio of geographically dispersed tidal lagoons could further enhance these system benefits.

Tidal Lagoon Power’s chief executive, Mark Shorrock, said: 

“Our offer to the UK Government is to contract Swansea Bay Tidal Lagoon for a lower subsidy per megawatt hour than Hinkley Point C.  While we await the Government’s response to this offer and to the independent Hendry Review of tidal lagoons, we have continued our development work on the subsequent programme.

“Today we have secured the grid connection for a tidal power station equal in installed capacity to Hinkley Point C.  Looking at the pounds per megawatt hour unit cost of new build power stations, nuclear is currently priced in the nineties, the latest offshore wind projects are expected to drop into the seventies and our models show Cardiff Tidal Lagoon beating them all in the sixties. 

“What’s more, by leveraging the commanding position taken by UK industry preparing for Swansea Bay Tidal Lagoon, the supply chain contracts awarded for Cardiff Tidal Lagoon will be worth more than £6 billion to UK companies”.

Phil Sheppard, National Grid’s Director of UK System Operator, said:

 “Tidal power presents a reliable and predictable source of renewable generation that has the potential for highly flexible operation in the future. We have worked alongside tidal lagoon developers to gain an understanding of the operational characteristics of the proposed lagoons. This infrastructure project will have a significant impact as we move towards an increasingly low carbon electricity network.”

We have reported about other tidal projects in UK:

• 320 MW Swansea tidal lagoon power station in Wales
• 6 MW Phase 1A of the MeyGen 400MW tidal stream energy project
• 2 MW tidal array in Bardsey Sound
• 3 MW tidal energy power in Gwynedd
• Enabling Future Arrays in Tidal (EnFAIT) Project
• 160 MW Wyre Valley tidal barrage on the Lancaster coast
• 160 MW Wyre Valley tidal barrage on the Lancaster coast