Chevy, gas-friendly to gas-freeVertical-axis wind turbine spins into business
Mariah Power says its Windspire vertical-axis wind turbine is now commercially available, after having passed performance tests.
The Windspire vertical-axis wind turbine
(Credit: Mariah Power)The Windspire costs $4,995, which includes the inverter, pole, and other equipment.
Typically, small-wind turbines such as Southwest Windpower's 1.9-kilowatt Skystream, are best suited for homes with a substantial amount of land.
Mariah Power said the Windspire is aimed at residential customers in urban, suburban, and rural areas. It has already been installed in a handful of U.S. locations.
"(Its) efficiency is on par with most propeller-based wind turbines, but it is priced much lower. It is also much quieter because the rotor glides through the air at only a third the speed of propeller blades, and it can capture wind instantly from any direction," Mariah Power CEO Mike Hess said in a statement.
The Windspire produces about 1.2 kilowatts, or 2,000 kilowatt-hours, per year, according to Mariah's brochure. It works best in 12 mph average winds or higher, and it generally requires half an acre of land, the company said. It's 30 feet high and has a 2-foot radius.
Martin LaMonica is a senior writer for CNET's Green Tech blog. He started at CNET News in 2002, covering IT and Web development. Before that, he was executive editor at IT publication InfoWorld. E-mail Martin.
I do not see why they think you need half an acre. I could put one in a 50' X 100' yard.
So this will give you 2000kWh each year. Electric company power costs me a total of 7.7 cents per kWh. If I get 2000 kWh per year out of this generator, that's only $154 worth of electricity. For my small frugal home, I would need three turbines just to eliminate my $60 a month electric bill. (I don't use electricity for heat, hot water, or AC.) For a larger home with a more significant electric bill you would need 5 or 8 of these things. Also doesn't say what total cost installed is. Let's say that installation costs $2000 and the turbine costs $5000. My seat of the pants tells me it would take like 50 years to recover your investment. Not good.
Don't get me wrong, I sure like the idea of solar and wind, but they've got to be a lot more cost competitive than this or they will remain a tiny niche for the guilt-ridden conscience trying to reduce their 'carbon footprint'.
A wind turbine like this needs to get down to the sub-$2000 range before it makes any real sense at all.
www.selsam.com has a similar sized dual propeller model for a similar price.
A Solar PV system that produces about the same amount of power annually is closer to $15000 after rebates.
Wind is often seen as a lower cost alternative that will work 24/7. Often a total system will include both wind and solar to make sure that some power is harvested continuously (when it is overcast & windy or sunny & still).
Photo Voltaic Solar Panels make DC
Hydrogen is not easier to store than oil, yet.
One question: The blades look 'fixed pitch'. How does this unit 'feather' in high wind to prevent over-rev damage? Does the entire unit have a spring loaded mechanism under the generator to allow the unit 'unload'?
http://www.ncdc.noaa.gov/oa/climate/online/ccd/avgwind.html
Namely, in many places in the country the average isn't over 10. Even in the "Windy City" is about a 10.
The other indicator to look at is that the average in many places in that data set are lower in the peak summer months. When a high pressure front parks itself over your city sparking a heat wave that is when you want your energy production to go UP not down. (yeah, yeah, the power will get shipped in from somewhere else. )
Solar and wind have problems in that they are very much tied to local conditions. They don't solve the baseload power generation problem . Power needed 24/7/365 that is independent of current conditions. They can be contributors to the total power produced
P.S. There pragmatically isn't a problem with math that shows 50 years to get return on investment. Anything past 10 year is very likely a non starter. So it isn't really material that the breakeven lies in 12 , 25 , 30 , or 40 years are all just as much of non-options as 50 years is. Anyone who says they are accurately costs of anything 10 years from now is blowing smoke. There are numerous economic variables that contribute to costs you are hard pressed to keep them accuratee and accounted for 10 year projections.
Unless you house lies inside of a natural thermal, where the winds are almost constantly blowing or your electricity is very expensive the economics aren't quite there yet.
First - cost. No doubt that there are issues with it. We need to get a level playing field to really compare though. Nuclear & coal get all kinds of subsidies (many of which are hidden: reduced taxes on facilities, etc.), while renewables get few. However many states (& the feds) offer incentives for homeowner renewables that can make them more affordable.
About high wind shutdown (furling/braking in a regular turbine): Take a look at their site (updated specs link - this is copied from them):
Speed Control Dual Redundant: passive aerodynamic; electronic
&
Wind Ratings
Cut-in Wind Speed 9 mph | 4 m/s
AEP Average Wind Speed 12 mph | 5.4 m/s
IPR Rated Wind Speed 25 mph |11.2 m/s
Survival Wind Speed 100 mph | 45 m/s
Birds: There is so much bull#$%^ floating around about how many birds (& bats) are "killed" by turbines. 2 things: First, read studies made on existing modern (not 10+ year old) wind farms. The "kills" are very, very low. Here in Vermont a wind farm in the southern part of the state has less than 2 kills per year total on 13 turbines. Second: Do you know how many birds are killed by large windows in homes & commercial buildings? Thousands every month. Do you want to ban all windows too? How many are killed by cars, trucks, buses & airplanes? Thousands more. How about pet cats? The list goes on....
The whole bird/wind power subject is perpetrated by NIMBY's that refuse to accept that we have to do everything we possibly can to reduce (eliminate) our dependence on oil. Is wind the answer? Of course it's not the only one. First is conservation: insulate, use higher efficiency appliances, etc. etc. Then we need to put together a balanced portfolio of power sources that includes wind as a component.
OK, done ranting ;-) I'm tickled to see someone working on vertical turbines - as many have called the concept dead. Only real world use will show whether or not they are viable.
Most wind turbines - even carfully sited ones - have an effective output equivalent to about 20-25% of their potential. So for a well-sited 2kW turbine, you might expect ~4000kWh. 2000 kWh sounds about right for a non-ideal location.
Half an acre seems a lot of land for a slim turbine like this!