“At the rate the WT6500 [off-grid wind turbine] is delivering power at our test site, it would take several millennia for the product to pay for itself in savings—not the 56 years it would take even with the 1,155 kWh quote we received.”
Is there a role for new renewables, specifically wind and solar PV in our electricity generation portfolio? And if not at the industrial-scale, grid-feeding level, what about at the micro-turbine level for local electricity use? This Consumer Reports (CR) study answers just this question.
Before examining the verdict, CR’s claim that wind power is the fastest growing source of new electric power deserves a critical comment. “Fast growing” from a small base too often is hype over substance.
Take the example of the lemonade stand of a little girl on our street, Suzie, just this summer. She sold one glass the first day, four the second, and 15 on the third. I’ll bet she is the fastest growing soft- beverage maker on the planet, but the big soft drink industry is not much concerned. I know this is a very simple comparison, but the lesson should be clear.
As far as having stand-alone wind turbines to meet energy needs is concerned, and basically this is what we are talking about here, is there a role? Well yes and no. It sort of depends.
A Little History
It might come as a surprise to many, but the U.S. was the world leader in wind turbine capacity for most of the 20th century. A later comer to this scene was Germany, which temporarily took the lead in the late 1990s, and of course lost it again in the early 21st century. The Germans had the worst record for renewable energy use in Europe and felt they had to do something about it.
The U.S. was the world leader for so long because of the size of the country and the limited extent of the electricity grid in some rural areas for much of this period.
What were the wind turbines used for? I’m not sure, but I imagine with some confidence it was to provide electricity to pump water and possibly to provide some lighting at night. Note the storage capability that pumped water provides, and wind tends to blow more at night than during the day.
Another interesting perspective is China, the major producer of off-grid wind turbines (100w to 10 kW), and I can imagine the domestic applications are similar to the U.S. as described above for remote areas.
What Role Micro-Turbines?
So what is the role for micro-turbines in modern societies? I suggest three:
(1) A hobby for those so inclined;
(2) A statement about one’s belief in the technology and be seen to be doing something about what the “experts,” as well as our democratic governments, are telling us we should be doing for a variety of reasons, and
(3) Some simple off-grid application.
Otherwise, wind turbines have no role today and for the foreseeable future, which is probably the next 50–100 years or so, if at all. Forget about the wild schemes that might be thought of, including high-flying platforms, and even offshore wind.
So what are the economics of micro turbines? Ed Perratore provides the financial analysis, and it is not pretty for all but the very rich (like Alec Baldwin’s proposed 120-foot-tall wind turbine in Suffolk County, New York).
Perratore’s “Recouping Cost of Wind Turbine May Take More Than a Lifetime” in ConsumerReports.com (August 6, 2012) follows:
Wind power has been the fastest growing source of new electric power, according to the U.S. Energy Information Administration. But if you’re considering a wind turbine to supplement your home’s power, consider our experience with one product, the Honeywell WT6500 Wind Turbine, a cautionary tale.
Among the few wind turbines that can be mounted on a roof, the WT6500 is similar to traditional wind turbines: Any unused energy it generates can be sent or sold to a utility for credit off your power bill. But it’s quieter than traditional turbines, and, according to the manufacturer WindTronics, starts generating power at lower wind speeds. The company claims the unit starts spinning from winds of a mere 0.5 mph—with electricity generated from only 3 mph. Traditional gearbox wind turbines, said the company, require at least 7.5-mph winds to start generating power.
A tool on Windtronics’s website had calculated we’d get 1,155 kWh per year at the 12-mph average it predicted for our area of Yonkers, New York. And the authorized installer, during his initial visit, didn’t say the roof of our headquarters might generate any less, but that rating is at a height of 164 feet, not the 33 feet WindTronics requires for rooftop installations.
In the 15 months since the turbine was installed, though, it has delivered less than 4 kWh—enough only to power a 12,000 Btu window air conditioner for one afternoon. A company representative in charge of installations worldwide recently visited our offices and confirmed that our test model was correctly installed. What’s more, he told us that while the WT6500 should start generating power at about 3 mph, the initial juice goes just to power the system’s inverter, which must be running before it supplies any AC power elsewhere. The true wind speed needed to start producing AC while the inverter is on is 6 mph, not far from the 7.5 mph needed by a traditional gearbox wind turbine.
The Honeywell costs $11,000 installed, comes with a five-year warranty and has a 20-year expected product life. But having a thorough site analysis by a manufacturer-authorized installer, backed by your own research on websites such as the National Renewable Energy Laboratory, is vital.
At the rate the WT6500 is delivering power at our test site, it would take several millennia for the product to pay for itself in savings—not the 56 years it would take even with the 1,155 kWh quote we received.