Shoppers from Dudley to Somerset in the UK are seeing new ‘work of art’ wind turbines generate electricity for Tesco supermarkets. The 6kW “Ropatec” wind turbines have two vertically driven rotors instead of the usual propeller blades on a horizontal axis. Vertical axis turbines are notorious for not being as productive as horizontal axis turbines as they do not have those large surface areas to capture the wind power that long blades provide.
Tesco spokeswoman Melanie Chiswell said: “It is true it will not produce enough energy to power the store but it will make a bit of a contribution.
“We try to do the best we can within the development confines available to us. We wouldn’t waste our time installing something that was useless.”
A spokesman for GallifordTry, manufacturer of the turbines, defended the turbine energy output and said: “In the right conditions they have an energy output of 6kW, enough to power four houses for a year.”
This is clearly a misleading statement as the turbines will not be operating at full capacity. No information about how much electricity the turbines are likely to generate is given. I hope that the majority of small scale wind turbine manufacturers provide as accurate information as possible about their turbines and that the customers who purchase them are not just doing so for “visual effect” PR reasons. If this is not the case the industry risks damaging the reputation of all wind energy. A report on small scale roof top wind turbines has recently been published and is very useful for anyone considering purchasing a wind turbine.
Solar Sasch
February 3rd, 2009
You nailed it on the head – simply stating that the wind turbine has a (peak) power rating of 6kW is like saying you have a fast sportscar that goes 200mph when the question wasn’t how fast it go but how far did it go. With roads with speed limits chances are the car is never exceeding much beyond 60mph on average. What’s important is what is the estimated energy output (kWhr and not kW) for the average wind speed for the location in question.
Usually the peak power rating of a small wind turbine is assuming a 25-30mph wind – which hardly any location on the planet gets on a regular basis. Wind speed to power output of a turbine is a cubic relationship. So if this windy site only averages 10-12 mph it’s likely that the turbine is produces an instantaneous power output of around 750kW.
Vertical Axis Wind Turbine Market Continues to Expand | Wind Energy Planning
October 24th, 2009
[...] wind turbines. In the UK, supermarket giant Tesco has installed several “Ropatec” vertical axis wind turbines with a rated capacity of [...]
muscle relaxer
December 10th, 2009
You need think about it. Despite the emails, the overwhelming evidence showing global warming is happening hasn’t changed.
“The e-mails do nothing to undermine the very strong scientific consensus . . . that tells us the Earth is warming, that warming is largely a result of human activity,” Jane Lubchenco, who heads the National Oceanic and Atmospheric Administration, told a House committee. She said that the e-mails don’t cover data from NOAA and NASA, whose independent climate records show dramatic warming.