The news this morning, that the Atlantic Array of wind turbines in the Bristol Channel has been cancelled, makes me quite sad and angry. Here is a relatively simple way in which we can reduce our carbon emissions and our dependence on energy imports, but it seems that Britain is now a country where such simple things do not get done. It is very easy to be disheartened by this, and I see few reasons not to be so.
One of the main objections to the array of wind turbines was that they would be an eyesore. Nine miles offshore. I’ve walked close to a farm of wind turbines on a hill in Ireland, and I found it a bit unnerving. Close to it becomes apparent that the tips of the turbine blades are travelling impressively quickly, and this made me a bit nervous. I can understand that people would have objections to turbines being built on hillsides where they could enjoy walking, but I believe that in many cases they are a necessary evil. However, nine miles offshore?
Are these people insane? Do they not realise that the turbines would appear tiny at such a distance, for all that they would have been 220m tall? It reminds me of the Father Ted episode in the holiday caravan with the toy cows in the caravan and the cows outside in the field: “This one is small, and that one is far away”.
Thanks to the wonder of Mathematics, one can work out just how small the turbines would appear at a distance of nine miles, which is 72 furlongs, or 15,840 yards. 220m is 240.6 yards. The angle subtended by the turbines, theta, can be calculated thus:
theta = arctangent (240.6 / 15840) = 0.000265 degrees
If I hold my arm out in front of me the distance from my upright thumb to my eye is two feet, or 24 inches. So to work out what height of thing at that distance will subtend the same angle as the wind turbines at a distance of nine miles we use the following calculation:
height at two feet = 24 * tan(theta) = 24 * (240.6/15840) = 0.36 inches = 9.3mm
That is a couple of mm shorter than my thumb nail.
What we have worked out – which we could have used ratios for rather than the tan function – is that if one holds out your arm in front of you and points your thumb skyward then the size of the wind turbines in the Atlantic Array at a distance of nine miles would be smaller than the size of your thumb nail. This is tiny.
Thus we conclude that the vociferous opponents of the now cancelled Atlantic Array were, indeed, insane, or else moronic and cretinous.