Wind energy a simplistic solution

TO great media fanfare, a group called Spirit of Ireland recently launched its proposal for wind energy in Ireland along the lines suggested by Prof Igor Shvets last December.

They propose that wind, along with pumped storage of water, could provide all of our electricity needs as well as much for export.

I wish to make a measured response.

As their advertisements and website are short on numbers, I have to rely on Prof Shvets’s figures and assume that is what is now being proposed. The proposal is to instal 6,900mw of wind generators which, given a load factor of 35%, would provide an average of about 2,400mw of electricity. Our requirement can easily be 5000mw, so the proposal would provide less than half of this.

For pumped storage, reservoirs of a total area of 2km by 2km, with a depth of 20m and a height of 250m above sea level, are proposed.

Using first-year college physics one can calculate this would only provide 5000mw of electricity for less than 11 hours; not very useful if we have calm weather for a week or more.

For example, using EirGrid’s figures, wind only provided a negligible 60mw on average for six days between September 23-28 last, which is less than 5% of the installed wind capacity. To suffice in this situation, 20 times the proposed pumped storage would be required.

This is impractical and enormously expensive. If, when the wind fails, we were to rely on interconnectors to Britain and France we would need to build 10 of the type now being proposed (€550m each).

This always presupposes electricity is available from these countries and the cost is likely to be very high.

The proposal is obviously very simplistic and very impractical. To say it could be achieved in five years is mind-boggling.

While we are right to consider sustainable sources, it is my opinion that renewables alone will not solve our energy problems and that we are on a dangerous road led largely by the Green party.

Our energy problems will become so serious we must urgently consider all options, including renewables, strict conservation measures, nuclear power and the role of dwindling fossil fuels (though they have carbon dioxide emissions).

Philip W Walton

Emeritus Professor of Applied Physics

NUI Galway