Adopting tidal power alongside other forms of renewable energy can “significantly enhance” energy security and help communities to fulfil their clean energy ambitions, a new study has shown.
The University of Plymouth study, published in the journal Applied Energy, found that installing tidal stream systems, in addition to solar and offshore wind farms, is around 25% more effective at balancing supply with demand than just relying on solar and wind technologies.
Using tidal technologies as part of a renewable energy mix can also reduce the space required for power generation facilities, both on land and at sea, by around 33%, as well as reduce their visual impact since much of their operation is below the sea’s surface.
Adding tidal can also help to reduce the levelised cost of whole-system energy, relative to solar and wind systems, because it reduces the requirement to access expensive reserve supplies.
The study focuses on the Isle of Wight.
The island plans to generate as much renewable energy as it consumes, and achieve net zero emissions, by 2040.
To achieve this, it will need to find ways to generate an average of 136MW of electricity through clean energy to meet its future projected annual demand.
The island’s primary source of power is a gas-fired power station, while solar power generates 80MW.
Plans for a nearby offshore wind farm were refused in 2015 on the grounds of its perceived visual impact.
The island’s tidal stream potential, meanwhile, has not been fully explored.
To understand some of the challenges of achieving the island’s goals, researchers developed a model which takes into account the need for supply-demand balancing, the whole-system cost of energy, and the spatial coverage of the renewable energy projects.
The researchers found that installing 150MW of solar power, 150MW of offshore wind, and 120MW of tidal stream capacity maximises both supply-demand balancing, and the magnitude of maximum power surplus – by 25% relative to the best performing solar and wind systems.
Tidal stream adoption also minimises the magnitude of maximum power shortages and surpluses across the year by 11% and 24% respectively.
The study was led by Danny Coles at the University of Plymouth – working with the European Marine Energy Centre, Hydrowing Ltd, Perpetuus Tidal Energy Centre, and the University of Edinburgh.
It builds on previous research which showed tidal stream power has the potential to deliver 11% of the entire UK’s current annual electricity.
Coles, Research Fellow on the INTERREG V A France (Channel) TIGER Project at the University of Plymouth, said: “Tidal stream energy provides a predictable, reliable source of renewable power that, if harnessed, can complement the variability of wind and solar.
“Our results show that adopting a combination of all three can reduce reliance on imported power and volatile prices. This is particularly relevant to the current energy landscape, when cold weather is increasing heating demand and millions will be paid to use less electricity to avoid blackouts.
The research is already being used by the Isle of Wight Council and Scottish & Southern Electricity Networks to assess the scope of work needed for grid upgrades on the island.