The fact that Britain is an island nation has led many to claim over the years that the country can largely be powered by wave energy. Yet more than 40 years after the UK government first began investing in wave-power research, only a handful of pilot projects have been installed.
There is a reason why wave power has still not been commercialised, says influential energy advisor Michael Liebreich, who founded analyst Bloomberg New Energy Finance.
“Wave power will not be competitive,” he tells Recharge. “The idea of using big wave-generating technology — and I say this with the best will in the world, I would love it to work — it's just that the amount of steel, the amount of concrete that you need to use to make it survive the storms… because once you make something heavy, it tends to then reduce the amount that it wants to move.
“And also it's quite chaotic, it's already a high-entropy source because waves come from different directions and they bounce off things and so on. So the amount that you can harvest from waves relative to the sheer weight of the kit [is too small].”
Liebreich also rejects the notion that the island nations such as the UK should focus more on wave power than onshore wind to prevent Nimbyism.
“Wave will get the same Nimby pushback as onshore wind because as soon as somebody comes and says, ‘where you used to go on holiday as a kid… we're going to put a wave power generator just along there and you'll be able to see it from the shore.’, it’ll be, 'oh no, we won't be able to do that'. And you can go around the coast and you can immediately find the communities and the people who will object to any location used for wave power because it will be these great big things [installed] where it's wavy, which is near the shore, which is where they can be seen. And they will change the amount of sand or pebbles that accumulates on beaches.
“And so it's a fallacy to think that we'll be able to do wave [power] any easier than we can do onshore wind from a social perspective.
“That doesn't mean we can't do it somewhere. I think where wave might work would be for local communities or, for instance, desalination on the coast of Africa or Southeast Asia where you have a need for fresh water and you've got waves. Let the wave create pressure, and use that pressure to directly drive reverse osmosis.
“Or the military might use it for naval bases or there might be distributed wave [power] where you use it for emergency [power] supply.”
Similarly, Liebreich believes that tidal lagoons will remain too expensive (unless a breakwater needs to be built anyway). He points to the £1.3bn ($1.62bn) 320MW Swansea lagoon scheme, which called for a 9.5km of new seawalls, and was last year rejected by the British government on cost grounds, saying the £92.50/MWh strike price (which would have far higher were it not for a promised £200m cash injection from the devolved Welsh government) was much more expensive than other renewable technologies.
But Liebreich believes there is a future for tidal-stream turbines.
“Tidal is expensive, but it's output is more valuable because it's predictable. So you can rely on tidal to make all the hot water that a city needs for the next 12 hours, for instance. And potentially, if you look at an island like the UK, which has got tides at different times, you could start feeding it into the transmission grid and it becomes very dispatchable — very nice.”
He adds that despite the inefficiencies, politicians may well choose to decide to invest in wave power and other costly technologies.
“We’ll still find that politicians will put money into direct-air capture, solar roads, wave power and hydrogen cars because all of these things run off the most abundant renewable resource known to politicians — taxpayer's money.”