Four months later we had a new turbine and new blades and for just over a year things were fine. We generated about 8000KWH during that time, which, while less than the sales pitch, was perfectly acceptable. We had an independent installer round for servicing and he advised that he would be surprised if we got less than 10000KWH per year, so our site location is clearly not bad.

Then in July 2008 we had a major electrical failure. This turned out to be a known overvoltage issue. Four months later all the electrics were replaced along with 3KW heat dumps to prevent overvoltage in the future. We had two 2.8KW inverters on loan as a 6KW unit was not available. Over the next 12 months we generated only 4000KWH. This was obviously a disappointment and I was advised by Proven that the two smaller units would be less efficient and hence my lower generation.

Eventually, we managed to get a replacement 6KW inverter and after many replacement chips and reprogrammings of said chips, we appeared to have a working system again with all the overvoltage protection built in! I couldn't be happier. Seven months on and we appear to be heading towards an annual generation of between 2500 and 3000KWH!!

So each time Proven 'fix' my system my output is approximately halving. Is it possible that the wind speed in the UK has been dropping off for the last four years or is there likely to be a software solution? I understand that my new 6KW inverter has the latest 7 phase curve in its software which should be more efficient but even on very windy days it is often generationg just a few hundred watts and also sometimes disconnects and appears to be unable to reconnect due to the very high voltages.

The annoying thing is that our all-electric house uses about 10000KWH per year and we should be generating pretty much all our own requirements.

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geoff
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