Simon Johnson, chair of Tamworth and District Green Party (Herald letters April 12) wants an informed debate on the best way forward about renewable power, and in his words does not want to fall back on fear, prejudice and conspiracy theory.
Let’s start with a few facts:
When the wind blows and let’s say about 200-300 wind turbines start to generate, a single coal-fired or combined cycle gas unit is shut down but has to be kept on hot standby to come on when the wind stops.
This wastes coal or gas; it causes greenhouse gas emissions without producing power, discharges steam to waste in large quantities, wasting chemicals and other products and uses labour and other resources in totally unproductive work.
But the problem does not stop there, when the wind stops blowing, before the coal or combined cycle gas unit can come back on load again, steam has to be blown to waste until the correct dry steam conditions are achieved prior to generating electricity again.
This can take several hours and again wastes a terrific amount of fuel, water, chemicals etc and again produces emissions to the atmosphere without any electricity generation.
With our climate, the coal or gas plant are likely to be ready to generate about the time the wind starts to blow again – ie They would be on and off like a yo-yo.
If wind energy capacity is allowed to become too large this delay in bringing coal or gas units on line when they are needed, will cause serious problems for the National Grid and power cuts may become a real concern.
However, when wind power is used as a small supplement to our energy supply the intermittent nature of their generation can just about be accommodated. But don’t let’s kid ourselves it’s not the answer and I think all those people trying to convince the public that it is, should spend some time trying to understand the inefficiency and technical issues involved.
Indeed, I think it is imperative that MPs, councillors, planners and decision makers should take technical advice on how a large expansion of intermittent wind energy will be accommodated on the national grid. They should also ensure they understand the waste of energy and emissions that will take place in a conventional power station whilst they are waiting for the wind to stop blowing and their units have to come back on line.
Like Mr Johnson I also wish to ensure my children and my grandchildren inherit a healthy and sustainable place to live. But I know from my experience as a long serving power station engineer and manager it will only be achieved by making informed decisions and will certainly not be achieved if the same entrenched views are continually preached without fully understanding their consequences.
He speaks of fear, prejudice and conspiracy theory; well, I hope my response helps him to examine his own thinking.
Mr C N Meredith, via email.