Comments on: Study delivers blow to urban microwind turbines

A multi-site study in the U.K. finds that a marginal wind resource, particularly in cities, means that rooftop small wind turbines are unlikely to meet manufacturers' claims.

[ittesi259]

Wow...maybe its to early in the morning but where is Manhattan2 with his babble about Solar Transfer and how great it is but tells us nothing about it?

[The_happy_switcher]

"Small wind turbines attached to individual homes work fine unless you have lousy wind. " wow, I wonder how much money was spent on this study that concludes that windmills don't work very well without wind? What's next, lightbulbs don't work very well without electricity?

[Michichael]

Hardly! We need proof that water is wet first.

[rapier1]

Its sort of important to actually quantify these things. For example, if Company A says that Product B will produce 8 kilowatt/hours with a 5MPH wind its useful to know if it will actually do that. Especially if a lot of people are spending money on these things. In fact, if you read the article you'd pick up on why knowing how a small wind turbine would work in urban environments is important.

[sanenazok]

I completely agree with the Harvard rep. The turbines and panels are meant as an enviromessage ("outward symbols of our commitment to renewable energy and sustainability here on campus") to the local leftists that the university supports green causes. Next, there'll be a study that the only way to make these systems self-supporting is a giant government subsidy. Good thing government money falls from the sky like manna!

[-_o]

Anyone else feel like the article could have cut off "Poring Over Wind Maps?" That section has nothing to do with the study. Seemed like a combination of filler and subtle marketing.

[carlhage]

Interesting study. What matters is the cost/kWh/year. Because power is proportional to the cube of wind speed and wind speed rises dramatically with height, the tall turbines get much more power. Power is proportional to the square of the rotor diameter, so you'd need 10,000 1m turbines (on a 100m tower) to equal only 1 100m turbine, so it seems hard for urban wind generators to compete with the large turbines sited optimally. In this study, the average turbine generated <$10/year of electricity, and the best performing unit generated <$100/year. (They sell the data for each station for more money than was generated in electricity in a year! :-) Part of low performance was due to being broken or shut off, so the average would have been <$30/year if running all the time.

No mention was made of the cost/unit. The turbines look to be ~US$2-3,000, without the inverters.

It looks like UK government rebates are 30% of installed cost-- it would be better to have a production credit so the incentive is based on the kWh generated. That would move the subsidies to the most efficient installations.

It was interesting that the measured wind-speed vs power curves differed so much from manufacturer's data sheets.

[smithenergy]

A Crowd Sourcing map has already been started to map where renewable energy is being generated - go to www.buildbabybuild.net/blog/residentialmap/ to add new locations.