Low Carbon Accelerator, the first AIM-listed private equity fund to invest in alternative energy companies, has already got quite an interesting spread of investments - 8 in total.

The one that really caught my eye was their £4.5 million investment in Proven Energy, a highly respected manufacturer and installer in small wind turbines, ranging in size from 2.5 kilowatts to 15 kilowatts. Proven wind turbines are deemed to be the most solid and reliable on the market, not least because they are "heavy metal" and therefore unlike conventional megawatt class turbines, can work in hurricane force winds. Obviously it helps the firm that they are based in Scotland, where the climate can be unforgiving and for many, electrification by the national grid is not a possibility.

But it's the urban application that fascinates me. Here's a Proven wind turbine I drive by quite regularly on the Wandsworth Roundabout in London.

I'm always drawn to look at it and I have to say, it is almost never not turning at quite a speed. I gather that BP are rolling back their solar programme for their petrol stations and using micro wind turbines where possible instead - the economics are simply much better. Small wind turbines have been bashed in the media quite a bit, but I still think that in cost, output and potential, they will still beat solar pv hands down, for some time to come.