While it always seems to take a back seat when compared to solar and wind power, the challenge to utilise the power of waves and produce electricity from the ever changing tides has been literally bubbling away under the surface in recent times. There are a good few experts who believe that if we could just find the right way to unleash this potential in the UK, it could provide a significant amount of the power we need and make us truly energy independent.
Forget nuclear and fracking, the future is tidal energy…at least if we can get our act together.
Sihwa Lake Tidal Power Station
While here in the UK we wait for the Government to make up its mind on the Swansea Tidal Lagoon and the five or six other sites that have potential in this area, South Korea is already way ahead. The Sihwa Lake Tidal Power Station is officially the largest tidal power station in the world. In fairness, the Koreans have been planning this since way back in the 1970s but it wasn’t until the noughties that anything started to get done.
The current development cost about $560 million and consists of ten water turbines that are capable of generating 254 MW – a yearly output of around 550 GW for the local area. While tidal power has its environmental detractors, in this case the power station has actually improved water quality in the lake.
La Rance Tidal Power Plant
It’s not just our distant friends in the East who have been making progress. France has also started to embrace tidal power. Head to Brittany and you’ll find a 240 MW station on the Rance River – it’s actually been there since way back in 1966 and is the oldest tidal power station on the planet.
What this shows to detractors of the Swansea Tidal Lagoon is that tidal power has already proven to be effective and has been providing countries with power for some time now. Up in Scotland, off the coast Stroma, another potentially huge project is underway. If things go well, the MeyGen tidal installation could generate as much as 398 MW.
The Problem With Tidal Energy
There’s no doubt that many believe our oceans hold a huge, untapped resource for creating renewable energy. But there are actually a few big problems to overcome and which need more research before we all start shouting hallelujah.
First, you have to have the right tidal conditions for installing a project like this – there needs to be around 7 meters or more of tidal range. Secondly, tidal power goes in cycles. Essentially the sea goes in and out so your installation won’t be producing electricity every second of the day. This is way some advocates are more focused on deep sea tidal projects that have the capability of producing power 24/7.
Finally, the cost is still high. The estimated price tag of the Swansea Tidal Lagoon is around £1.3 billion which many see as prohibitive and we all know what happens to price estimates in the end. This has led companies like Ecotricity to suggest, once again, that it would be cheaper to produce offshore and a lot more reliable.
Offshore tidal installations also pose their own problems, however. Many developers are working on new ideas such as the kite turbines off the coast of Holyhead in Wales but investment in this area has been lower than for options such as solar and wind. The cost of maintenance depends a lot on the type of installation and something static could end up costing more than a project like Swansea.
Another problem that could have a big impact in how much tidal power we deploy in the future is the environmental question.
While the Sihwa Lake project in Korea found that the tidal plant helped clean up their water, it was, to be fair, pretty polluted to begin with. A tidal lagoon like that planned in Swansea and other locations around the UK will undoubtedly have some impact on the environment and activists and wildlife groups are likely to get involved. The trouble is that the true cost in this area will not be known until we have a working plant to get data off. If planning permission is to be granted for Swansea, an environmental impact assessment will have to be undertaken and the developers will then have to put in or propose measures to mitigate that impact.
For the moment, the future of tidal power, particularly in the UK, remains unclear. Financially, the Swansea Tidal Lagoon has been given the nod from all the right examining bodies. It has plenty of advocates and plenty of detractors. There’s still the hint, however, that the Government will continue to stall and that we may not get an answer for some while. In the end, the cost of doing nothing may well cost us a clean energy solution we could all get behind.
