Small wind system tackles big issues
As I’ve said before, the market for small wind turbines doesn’t get much respect on the larger renewable-energy stage, and that’s probably because many of the products out there don’t live up to their claims. I’ve seen a dozen or so newcomers hoping to corner the small-wind market with their vertical-axis wind turbine models but so far nothing major ever comes of their efforts. Part of the problem with small wind is that you typically need to erect a standalone pole — separate from any residential structure — because the turbines cause very annoying, and over time destructive, vibrations. The pole itself adds extra cost and is unsightly if you’re planning it for any suburban or urban area, so these systems only end up at cottages and other rural dwellings where there’s lots of space and neighbours can’t complain.
Noise is also an issue, yet another reason to locate it a comfortable distance away from a residence. Vertical-axis turbines are being designed to address such problems, but progress — or perhaps it’s just acceptance — has been slow. Cleanfield Energy, Raigatta Energy, Tesnic are just a few of the Canadian companies going after this market.
A Grand Rapids, Michigan-based company called Cascade Engineering hopes to overcome some of these technical issues with small wind but using a design that improves upon traditional horizontal-axis turbines. Cascade’s Swift turbine, which has limited distribution in both the United States and Canada, has five blades instead of three that are connected by an outer ring. The ring, the company claims, dramatically reduces noise and vibrations by diffusing air flow as it travels up the length of each blade to the tips (which is typically the source of noise).
The Swift turbine has a rated capacity of 1.5 kilowatts and supposedly generates up to 2,000 kilowatt-hours annually, which isn’t that much considering the typical home in downtown Toronto consumes about 10,000 kilowatt-hours a year. You’d need five Swift turbines, at $10,000 a pop after rebates, to offset all the electricity your home uses every year. If you sold that 2,000 kilowatt-hours into the Ontario grid at 11 cents per kilowatt-hour under the province’s standard offer program, you’re talking a 45-year payback. Not good, to say the least.
The bottom line is that I’ve yet to see a small-wind turbine that makes sense in a grid-connected scenario, at least if your plan is to sell electricity back to a jurisdiction like Ontario that has feed-in tariffs. If your plan is to use the electricity to merely offset your electricity use (i.e. net-metering), the payback is even worse (if you can imagine). So really these products only make sense in a rural or cottage setting where getting electricity to where you want it might require paying the local utility $20,000 to put in a new hydro line. So, for these products to be of any economic use in urban or suburban settings, the price has to come down by more than half — preferably two-thirds — before it begins to become attractive.