Sunday, 16 September 2007


It's been a bright, blustery day with pelting showers. The sky is a pageant of clouds and when they part enough for the sun it sets the bracken to bronze. The birches are slowly giving up their leaves, one by one. With winds like this, as each leaf ripens to gold it is blown off, so the trees remain green overhead, thinning, with only the floor of the woods taking on autumn colour.

This morning the wind seemed light enough to row from the caravan at the shore to the bridge, which is its nearest road access. It's not far, maybe 300 metres. Two dead batteries needed shifting, and it was time to tackle that job. They're heavy. These two batteries were from the original set when the wind generator was installed 8 years ago. After they weakened about 3 years ago they were relegated to the caravan, where they have been fed by a solar panel and used to power the music and lights down there. They have finally given up the ghost. Battery technology is rubbish - they are the weak link in the off-grid system, predicted to fail in as few as 3 years and when they do they are full of toxic non-renewable chemicals so they are a pain to dispose of. We should be pretty pleased to get 8 years out of them. Compare the solar panel, which is guaranteed for 25 years, and the wind generator itself, which should last for decades, with the odd replacement bearing. We won't solve the planet's energy problems until we sort battery technology. Who's on that case?

The really smart solution is a battery system that uses the wind power to split water into hydrogen and oxygen, and then a fuel cell to generate electricity from the hydrogen when you need it. That's what the PURE project does. Unfortunately it's still way out of our price range and not at our kind of scale. At least lead acid batteries are relatively cheap, though that's all they have going for them.

So, that's why I was rowing two big batteries up the loch this morning. The wind was surprisingly strong and kept blowing the boat sideways. At the uidhe - the 'throat' in Gaelic - where the loch narrows enough to bridge it, I was blown aground. Fortunately the tide was coming out so that acted as a counter-current to the wind and I managed eventually to get the boat up to the landing point and the batteries are now poised for recycling. On the way back to the caravan I was rowing against the wind. It felt like a lot further than 300 metres. Good exercise.

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