The Folkecenter for Renewable Energy (FC) has again published a handy report cataloging small wind turbines available worldwide.
The FC’s 2012 Catalogue of Small Wind Turbines is the one neutral source of product information worldwide on small wind turbines less than 50 kW in capacity.
While there are several online sources that list manufacturers and their products, these are commercial web sites where advertisers pay to get placement and prominence on the site. I’ve seen some of these web sites and the information they provide is “snake oil and bunkum” and unless you’re experienced in the wind field your best advised to stay away from them.
The catalogue uses one page per turbine, often with a photo, description, and a summary of the units sold and the years the product has been on the market. No where else have I seen such a quick summary of how many units of a particular product have been deployed. This is enormously useful in gauging the significance of a particular manufacturer and their products.
Disclosure: I received a fellowship from and lived at the Folkecenter in 1998 for four months while I was researching small wind turbines for my book Wind Energy Basics.
Frequently I get requests of the “What do you think of this product” from readers around the world. Now I can just scan through the FC’s Catalogue and determine whether “this product” is something significant or not-often they are not.
This data is also particularly revealing. Evance, a British manufacturer has sold 700 units of its 5-meter, 5 kW turbine. This is a remarkable achievement for a small manufacturer in the British Isles.
The data is also revealing for manufacturers who don’t report how many units they have sold, most likely because the number is so small.
The cataloging of units sold, moreover, give us a picture of the entire industry’s heft. Consider the two principle manufacturer’s in the US: Bergey Windpower and Southwest Windpower. They dominate the US market and have done so for years.
Nevertheless, their combined contribution is less than 100 MW of capacity. Bergey’s share is about 25 MW. And there’s no way of knowing how many of those turbines are still in operation, though Bergey’s turbines are the most robust on the market.
Southwest Windpower’s Skystream alone accounts for another 20 MW. But we should discount the contribution from Southwest Windpower’s Air series of turbines. The number sold is unlikely to represent the amount of turbines still operating. The early turbines were particularly unreliable. Many considered the product a “disposable” wind turbine. Thus, it may look like a lot of capacity but it’s not. So to with the Whisper line. It’s extremely unlikely that a larger percentage of the Whisper turbines are still in operation. (My Whisper lasted five years, no more.) My guess is that the Air series and the Whisper line contribute only another 10 MW at best. This brings us to about 30 MW.
Bergey and Southwest’s total operating capacity is probably about 50 MW-and this is after decades of development.
For a sense of scale, Germany installed 1,800 MW of solar photovoltaics (solar PV) in just the first three months of 2012. And while the yield of solar PV is half that of commercial-scale wind turbines, it’s about equivalent to that of small wind turbines. This puts the contribution of small wind in perspective.
The pages of the catalogue are organized by country, then by manufacturer. This gives an outsize presence to China and it’s not surprising that the Chinese Wind Energy Association is a co-publisher of the report.
Unfortunately, the listings by country don’t give a complete view of the industry and its products. For example, there are several suppliers listed under the USA who source their products from China. So the question is, are these Chinese turbines or American? In this cataloguing system they’re listed under USA, but in fact the American company imports the turbines from China. The US company may or may not have designed the turbine.
Take the Bergey XL.1. It’s listed under USA because Bergey Windpower is a long-standing US manufacturer. The XL.1 was designed by Bergey, but the last time I checked Bergey was importing the turbine from China.
The FC and its researchers can’t be faulted for not reporting where turbines are actually sourced. It’s a dark secret that some companies don’t want to admit. Trying to dig up this data would be a nightmare for any researcher.
Like most tables of such data, the tables begin with rated power. While not particularly useful, it is what everyone expects and for that the FC can’t be faulted for following convention.
Fortunately, they follow this with the more useful data on the rotor diameter for conventional wind turbines and the height of the rotor and its diameter for vertical axis wind turbines. And to avoid any confusion, the data tables also give the resulting swept area of the rotor. Believe it or not some promoters of small wind can’t be trusted to calculate swept area correctly.
It would be helpful if the FC would spend a little time analyzing the data in the catalogue. As it is the FC’s catalogue is just that: a catalogue of products and not a report on the status of the small wind turbine industry.
And it’s a weakness of such enterprises that the FC’s catalogue is only a snapshot in time. The market changes so rapidly-manufacturers come and go so quickly-that it’s out-of-date as soon as it’s issued.
Nevertheless, the FC’s catalogue remains the single best unbiased source for a glimpse at what small wind turbines are available on the world market.
Catalogue of Small Wind Turbines Under 50 kW: 6th Edition, 2012 by Katie Christensen, the Nordic Folkecenter for Renewable Energy; Kammersgaardvej 16, Sdr. Ydby, DK-7760 Hurup Thy, Denmark; firstname.lastname@example.org; www.folkecenter.net; 137 pages; 20 Euros for pdf version, 25 Euros paper.