Measuring wind power to see whether it makes sense to get a wind turbine has, until now, been either expensive or inaccurate. Now with the launch of the Power Predictor, it’s possible to take the risk out of what is a significant investment.

The device is the invention of Toby Hammond, managing director of Better Generation, who says: “Our intention has been to take the guesswork out of micro generation by creating a device that is not based on modelled data, which is often inaccurate, but on site specific data that shows anyone at home or at work, how much they could save by generating solar or wind energy.”

I’ve been one of the lucky people who had a sneak preview of the Power Predictor, I have been testing it out in my garden since April. We chose to put it up on the windiest day of the year, and had a hilarious time making a 6m high mast out of three lengths of baton screwed together, and trying to fix it (nearly) straight with a number of guy ropes and tent pegs. We took the cheaper DIY approach, but you can buy a ready made mast if you prefer.

A data cord comes down the mast to a little waterproof box which you tape to the mast at an easily accessible height. It’s pretty simple to enter the date, time etc, and press record. Then when you’ve got enough data (at least a month’s) you take out the data card and upload it to the Power Predictor website. You also put in data about your site, whether there are trees, houses or other obstacles around.

My report shows that the wind speed rarely meets the 4mph which the wind speed database states as the average for my postcode. The Power Predictor report is unequivocal – wind is not an option for me. Depending on what turbine I was to choose, payback times would vary from 390 years to 1087 years – and annual savings vary from £6 to £161. While I never expected wind to be a great option, I am somewhat taken aback at what a complete waste of money it would be. However, it's really good to know that, and if I had a borderline site, I’d definitely pay the £100 for a Power Predictor to check whether or not it would be worth taking the plunge.

The device also measures solar potential, and there I’ve got more hope. I’ve already got solar hot water panels and know that they work well. The report shows how various types of solar electricity (PV) panels might perform. For an investment of £12,800 I’d get annual cost savings of £324, generate just over 2MWh of electricity, reduce my carbon emissions by over 1,000 kg and have to live another 40 years to see it pay back its initial cost.

This tells me that if I’m thinking in purely financial terms, it’s not a good investment. What it doesn’t tell me is whether it’s suitable for my roof (which has dormer windows, and so potentially shading on the panels, and maybe not enough room), or the relative benefits of the different types of panel. But of course the answers to those questions are all to be found here on YouGen!

I really welcome the launch of the Power Predictor. The whole ethos behind YouGen is to help people to make informed decisions about renewable energy, and to be able to see through the hype, and only invest in appropriate technology for their site. This device means that more people can do that at a reasonable price. Congratulations to Toby and the team at Better Generation for a great new tool.

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