Popular Science readers: Please note that I have nothing to do with these companies, and so I can’t send you information about them. Please visit their websites instead.
Windside: http://www.windside.com (Finland) and Windaus Energy: http://windausenergy.com (Canada; site doesn’t render properly in Mozilla): both with near-identical twisted-savonius designs. Oh yeah, and a nice line in carping at the rest of the wind energy industry:
There are no flying ice blocks, leaking oil or cutting blades. (Windaus);
Most turbines don`t simply work. There is one turbine, which works. (Windside).
It should be pointed out that Savonius designs, being drag devices, are much less efficient than standard three-bladed horizontal-axis machines, which use lift. If you need a design without guywires, take a look at the Proven Energy machine. It’s very solid, and Scottish, too.
One has to wonder about lone voices in the wilderness. Once they start to drown each other out, it gets hard to tell which are the real deal, and which are not.
Addendum, 16 June 2004 — the note I’m sending out to request-for-information comments:
I’m afraid to say that there have been many wind turbine designs which deliver far less energy than their manufacturer would claim. If the websites are unable to answer your queries, I would be very cautious about investing in the design.
While it’s true that vertical axis wind turbines can capture energy from the wind in any direction, this is less of an issue in reality than you might think. In wind speeds that are useful for power generation, the wind tends to come from a fairly well-defined direction. Thus horizontal axis designs will capture as much energy as a vertical axis design, and do not have the same fatigue problems.
The Windaus and Windside designs look like drag machines. These are much less efficient than lift machines — which include most horizontal-axis designs. While drag machines may have lower noise from the blade tips (since they travel more slowly than lift machines), mechanical noise is usually the largest part of wind turbine noise.
It’s not that vertical axis designs are the great undiscovered secret of wind energy; they’ve been extensively tried before, and found to be less workable than horizontal axis designs. Canada invested millions into Darrieus turbine research in the 1980s, and the first company I worked for in the UK used to make vertical axis designs.
If you are genuinely interested in small wind turbines, I’d strongly recommend that you read around before choosing a design to use. Two resources I can recommend are:
• Home Power magazine: <http://homepower.com> — they’ve been using off-grid power for years. If they say a design works, it very likely does.
• any book by Paul Gipe, but especially his newest 2004 publication, Wind Power: Renewable Energy for Home, Farm, & Business: <http://wind-works.org>. Paul’s seen pretty much everything in the industry since the early 1970s.
Daily Kos Readers: ask my employers in the wind energy industry since the early 1990s if I know my stuff …