Tidal energy could be a game-changer for a greener, more sustainable economy as the EU moves towards a target of 40-percent renewables in its overall energy mix by 2030.
It could deliver 100 GW of capacity by 2050 – equivalent to 10 percent of Europe’s electricity consumption today.
European grants – including Horizon 2020 grants – have been instrumental in moving the needle forward in tidal energy research, and now the technology has reached fruition.
The next step is scaling up the prototype platforms so that tidal energy can become commercially viable and enter the energy grid in a meaningful way.
There’s just one hitch in this plan: cost.
Tidal energy is the new kid on the block in terms of the renewable energy market. All types of energy production require significant financial backing, but tidal energy companies are running into problems when they ask for support to scale-up.
Traditional funders, like banks, are either unwilling to invest at all, or else offer sky-high interest rates on their loans, making it commercial nonsense for tidal energy companies to accept. No bank seems to want to be the first one to give tidal energy the green light, only to see the scale-up efforts flop.
“It’s really about the promise that this industry will take off and reach some maturity,” said Jan Cornellie, project leader of the Clean Energy for EU Islands secretariat.
“At the moment, I think that’s also why the banks remain sitting on the fence – to see whether it’s really going to happen.”
To get off the ground, tidal companies need national governments to introduce revenue support schemes, guaranteed prices and decent bank loan rates.
According to Rémi Gruet of Ocean Energy Europe, “At national level we really need guaranteed prices to be put on the table. This is the way we developed wind and solar and there is no other way that we can do tidal. You can’t just ask a new technology to go and compete against an old technology. Especially when all the other energy sectors are subsidised.”
It comes at a time when rising energy prices are making headlines all across Europe. An over-reliance on wind power and gas has led to fierce price hikes. It’s something that could be alleviated if tidal energy was on the table, Gruet says.
“Having an additional flexible energy (ocean energy) on the grid will smoothen the peaks and lows of production and thus make matching demand easier. In times of high energy prices it means that ocean energy will lower overall costs of electricity as you need to resort much less often to expensive and pollution ‘peakers’ (plants you only use when you have a spike in consumption – mostly gas at the moment unless the country has access to hydro dams).”
The big advantage that tidal energy has over other renewable energy sources is that it is entirely predictable. Wind and solar energy rely heavily on the weather – when the wind stops blowing or the sun goes behind a cloud, no energy is produced.
But tidal energy relies on the gravitational pull of the moon on the earth, something that’s not likely to change anytime soon.
That’s part of the reason why it’s so attractive to innovators like Orbital Marine Power. They’ve designed a unique type of floating platform that consists of a cylindrical tube with the turbines on two retractable legs underneath the water. The advantage of the retractable legs is that they can be lifted up with hydraulics up onto the sea surface, which facilitates repairs much more easily, thereby cutting costs.
“For a competing technology that has turbines on the seabed, they’re going to need a heavyweight vessel to go down to retrieve the turbines if they needed to be repaired. That could cost up to £100,000 [€117,000] a day,” says James Murray, programme manager at Orbital.
“For our vessels, doing repairs might cost up to £5,000 per day. It’s a much lower risk, because everything is so much more accessible, and those retractable legs are a big part of that.”
Nova Innovation, which operates in Scotland and France, is another innovative company that is bringing down the costs of tidal power through new innovations. Nova’s turbine doesn’t require a gearbox, for instance.
“Fewer moving parts enhance [the turbine’s] reliability and extend the period between maintenance intervals from one year to two years – further cutting the cost of energy. The direct drive turbine is more efficient and more reliable,” says John Meagher, director of business innovation at Nova Innovation. “The M100-D turbine has lowered tidal energy costs by 30 percent.”
Reducing costs in this way should make the technology more attractive to financial institutions like banks, but so far that hasn’t been the case. Although costs for scaling up tidal energy projects are not particularly high compared to other energy projects, banks still seem to be nervous of tidal energy.
“It’s going to be €100m, but for a bank €100m for an energy project is not that much. To give you an idea, if you want to build a wind farm today it’s going to cost you anywhere between one million and one billion,” says Gruet.
“The issue is really not the size of the project. It’s that the technology attached is a technology that the banks don’t know.”