Warwick Wind Trials Gives Failing Grade to Rooftop Wind

By Paul Gipe

If further proof is needed that mounting wind turbines on rooftops is a bad idea, the final report on the Warwick Wind Trials is it.

The report, while bending over backwards to give the British small wind turbine industry the benefit of the doubt, clearly lays out the principle problems with rooftop-mounted small wind turbines–poor performance and noise.

Encraft, the private firm performing the study, provides a wealth of information in its report, including measured power curves using 10-minute averages for the

  • Zephyr Air Dolphin Z1000,
  • Ampair 600 (two units),
  • Eclectic StealthGen D400, and
  • Windsave WS1200.

The summary of the results is particularly damning but the entire report is worth reading.

“Of particular note is that turbines on our high rise sites, Eden, Ashton and Southern Court were able generate as much energy in one month as other turbines in the trial did in one year. It is unfortunate that these high performing turbines had to remain switched off for the majority of the trial following complaints about noise from the building residents. The best performing turbine in the trial generated an average of 2.382 kWh per day when in operation, equivalent to 869 kWh in a full year. The poorest site generated an average of 41Wh per day when in operation or 15 kWh per year, which is less than the energy it consumed to run the turbine’s electronics. [emphasis added]

“Overall the trial has painted a picture of an industry and technology that is still at development stage and is likely to make a tangible contribution to energy and carbon saving only on the most exposed sites and tallest buildings. The combination of this reality, aggressive and over-optimistic marketing by some suppliers, and the enthusiasm and credulity of the market (and regulators) has potentially led to an unfortunate outcome where the wind industry as a whole is in danger of suffering from a setback in credibility.

“The evidence form this trial is that such potential setbacks can be avoided in future by greater openness by the industry as a whole, and more effort to educate the market and opinion formers about the fundamental science and challenges of new technologies earlier. Micro-technologies need not fear customer resistance, because there are plenty of early adopters out there willing to give things a go. Sustainable technologies and a sustainable future require customers who are properly informed and able to take individual decisions that are both economically optimal and environmentally sustainable. Without open data this is impossible.”

Unfortunately, this report and the others that are now appearing have failed to dampen the unfounded enthusiasm for rooftop-mounted wind turbines by an il-informed public and the hustlers who prey on them.

As I try to explain in my new book, Wind Energy Basics, there’s a phenomenon at work here. The public wants renewable energy and wants to participate in its development. Where public policy, such as in the USA and Britain, prohibit it, people will take action on their own. Rooftop promoters understand this and take malicious advantage of the public’s deep-seated desire to do something.

Final Report, Warwick Wind Trials