Power from tidal lagoons could provide UK electricity generation’s missing link

Swansea tidal lagoon power scheme could be the UK's first.

Multi billion pound investment would provide payback with jobs, energy and an economic boost, say Douglas McWilliams, Oliver Hogan and Colm Sheehy.

A startling lack of urgency in replacing the UK’s ageing energy infrastructure has left us with the prospect of a ten year period between 2015 and 2025 with plants closing and electricity supply barely able to meet demand.

The temporary response has been to introduce an electricity ‘capacity market’ which pays a guaranteed price for electricity generators to produce at times of peak demand. The Government’s longer term response is to incentivise investment in a more diverse electricity mix that allows transition to a low carbon future. 

Our research found that a £35.4 billion investment over a twelve year construction programme would make an accumulated contribution of £27bn to UK GDP, creating or sustaining up to 35,800 jobs on average and up to 70,900 jobs at its peak.

Tidal lagoons (see note) could provide the missing link to this future low carbon mix – scalable, lower cost renewable power generation which is intrinsically predictable and a far cry from wind and solar power which are subject to intermittence and seasonality.

Tidal energy plants have a design life of 120 years which is far in excess of any other electricity generation technology.  In contrast to offshore wind farms, tidal lagoons have a low visual profile and therefore have far less of an impact on the marine landscape. 

It just so happens that the UK has some of the best tidal range resources in the world – estimated by the Crown Estate at up to 59 GW. A planned fleet of six tidal power stations with 15.9 GW installed capacity would harness a portion of this untapped resource to produce as much as 8% of the UK’s electricity needs – enough to power 7.9 million homes. The first lagoon planned for Swansea Bay (320 MW) is set to start construction in the first half of 2015, subject to planning permission.

The technology used by tidal lagoons is well-established – the La Rance tidal barrage station in Northern France has been successfully operating for 50 years. South Korea has one operational tidal barrage plant and has plans to build up to six more. Wave power technology on the other hand is in its infancy. Although significant investment has gone into the technology, it will take a lot longer to get to a point of commercial viability.

There is an estimated 80 GW of capacity at sites already identified as having commercial development potential around the world, amounting to a potential global market for tidal power worth £383 billion. As the first country to develop a tidal lagoon industry, the UK stands to reap the benefits from the development of international projects.

The Centre for Economics and Business Research (Cebr) last week published a report assessing the potential economic impact of building six tidal lagoon electricity generation facilities across the United Kingdom. 

Our research found that a £35.4 billion investment over a twelve year construction programme would make an accumulated contribution of £27bn to UK GDP, creating or sustaining up to 35,800 jobs on average and up to 70,900 jobs at its peak. The operation of the lagoons and the electricity they produce would contribute £3.1bn per year to the UK economy, creating or sustaining as many as 6,400 jobs. A further benefit is that the majority of the value of components and construction contracts required to construct and operate the lagoons can be sourced in the UK.

What our research demonstrates is that, not only does a tidal lagoon industry have the potential to make a significant contribution to the UK economy, but that it can also help secure our energy independence and create a brand new infrastructure industry that will support activity and jobs in the UK for many years to come.

Douglas McWilliams is founder and executive chairman of , the Centre for Economics and Business Research, Oliver Hogan is director and head of maroeconmics and Colm Sheehy is senior economist.         


Note: Tidal range is a renewable electricity generation technology that uses the differential between water levels inside and outside the lagoon (‘head’), created by the rise and fall of the tides, to generate electricity. Tidal lagoons – as opposed to tidal barrages which dams rivers and bays - involve the construction of a bund wall connected to the shore that encloses an area of the sea.