All energy sources – natural and nuclear – should be up for discussion

I WISH to reply to the letter headlined ‘Wind energy a simplistic solution’ from Prof Philip Walton (May 12).

I welcome his additions to the discussion on Ireland’s future energy needs. His active participation in a nuclear energy lobby group is acknowledged. Since my first lecture in December 2008 on energy storage, I have been surprised by the pressure put on me not to bring it to the public domain.

In my view all options covering both natural and nuclear energy should be open for national discussion.

However, inaccuracies in Prof Walton’s letter to you need to be corrected.

Average load requirement in the Republic is 2,500mw to 3,000mw, not 5,000mw. The peak is typically around 5000mw, but can go higher depending on weather, time of year, etc.

Spirit of Ireland proposes 2,500 to 3,000 x 3mw turbines in addition to the 3,000mw that will be connected under present plans. Two or three storage reservoirs will be built. The size of these is variable in generation capacity and length of storage.

This can range from days to weeks depending on how they are designed and used. Dam heights are in the range 70-100m. Reservoir sizes in suitable valleys range from four to more than 10 sq km – not 2km. Envisaged pump/turbine capacity per site is typically 1,000mw. Increasing the scale is very economical. More than 50 potential sites have been identified. Many have storage capacity from 100 gigawatt (gw) hours to several hundred gw hours.

Portugal is currently working on 10 storage-related dams. More than 200 hydro storage facilities are in operation worldwide and more are being built. Scale is increasing.

I agree that wind power alone is of limited value. Wind is intermittent and wind power needs to be stored for use when required.

In general, any renewable energy source (wind, solar, waves) is intermittent and we need to be able to make it available on demand.

I grew up in a uranium mining town in Ukraine. The consequences of uranium mining need to be seen.

Ireland is very fortunate. We have enormous natural energy. It can be the bedrock of our future prosperity and will spread wealth through the country and into local communities, businesses and homes. I welcome the nuclear lobby’s input. We need to discuss this as a nation.

See www.SpiritofIreland.org.

Prof Igor Shvets

Professor of Applied Physics

Trinity College, Dublin