Health Wales is highlighting the work of Welsh Crucible researchers – the cream of Welsh research talent. Dr Simon Neill explains his research into the impact of tidal energy and other sources of marine renewable energy
ANYONE living by the sea will be familiar with the twice daily rise and fall of the tides.
What is less familiar is that these tides cause the water to flow and in some regions these tidal currents can be very strong – such as past exposed headlands and through narrow channels. These regions of strong tidal flow have been identified as desirable places to install farms of marine current turbines or underwater windmills for electricity generation.
In contrast to wind energy, which is intermittent, this form of renewable energy is predictable. We can tell what the tides will be doing 100 years from now, but can’t tell what the winds will be doing tomorrow.
Much of my research is concerned with understanding how to maximise the tidal energy resource once tidal energy schemes are scaled up, making them competitive with other forms of electricity generation such as nuclear or coal-fired power stations.
I also investigate how these large tidal energy farms will interact with the environment.
One particular aspect of the environment which could be affected by large tidal energy schemes is the movement of sand around our seas. Tidal currents continually transport sand, feeding into coastal systems, like beaches and offshore sand banks. These coastal systems remove the energy from storm waves so are vital natural forms of coastal protection.
Any large tidal energy scheme which interferes with the processes maintaining these natural systems could make our coasts more exposed, affecting flood risk.
In my research, I use computer models to understand the natural movement of sand, and how this varies from year to year and from season to season.
I incorporate tidal energy farms into these models, and determine what impact energy extraction is likely to have.
I make recommendations on the scale and layout of schemes, which will be appropriate for different locations. For example, at a particular location it may be appropriate to site the planned tidal energy farm slightly further offshore to minimise interaction with the natural coastal dynamics.
Although tidal currents may be slightly weaker further offshore and less electricity will be generated, this could be a small price to pay if it prevents any negative impacts to our natural coastal defences.
One of the most exciting developments of this research is the possibility of strategically siting tidal energy farms to enhance coastal flood protection by geo-engineering the sand resource.
This is particularly relevant in the context of the predicted impact of sea-level rise on increased coastal flooding over the next few decades.
With the rapid global commercialisation of marine renewable energy now taking place, from prototype to large-scale electricity generation, it is essential and timely that research into understanding the resource and potential environmental impacts is being carried out now.
If Wales is to fully exploit its world-class renewable energy potential, it is important these issues are being investigated for Welsh coastal waters by researchers in Welsh universities.