Our renewable energy is going to England

MAX Wallis, of Friends of the Earth, Barry and Vale, is being less than logical regarding renewable energy (“‘Gappy’ power is a very risky business”, WM letters, May 16).

He is correct that tidal energy provides “gappy power”. The tide cannot generate electricity for 24 hours per day due to tidal flows, and night-time generation is obviously “out of sync with demand”.

He is correct that the “National Grid does not want gappy power” but his solution of “modern high-power storage systems using batteries or fuel cells” are laughably inadequate to power a nation of 64 million people.

The UK uses more than 60,000MW at peak winter demand. Batteries covering many acres would generate only a few megawatts (if that) and need recharging from the fossil fuelgenerated electricity of the National Grid!

Max Wallis does not mention the biggest “gappy electricity generators” of the lot: gigantic wind turbines, which produce nothing in winds below 10mph or in gusts above 55mph (great danger from shattered blades in strong winds).

At least tides are predictable, unlike the yo-yo-like wind which often goes AWOL (check gridwatch. templar.co.uk. UK wind energy provides only 5.5% of UK electricity as I write).

The truth is that Wales only uses 1,850MW of electricity on average and the new gas-fired power station at Pembroke in the far west of Wales generates 2,000MW.

Therefore all the renewable energy of Wales, plus Aberthaw, Baglan, Usk and Deeside fossil fuel power stations, plus Wylfa nuclear, must be powering England, not Wales. LJ Jenkins Gwbert, Cardigan