Today is raw, wet and windy with gusts up to 25 mph — a lousy day in most anyone’s book. But it would be a good day if I had a wind turbine in my back yard. And I soon will.
I have been interested in wind power (not just in the journalistic sense) since the '70s when the best you could do was a custom-made and often unreliable backyard eggbeater. It’s hard to believe that two of the most influential inventions of the late 1800s was the mechanical wind turbine for drawing water out of the ground and barbed wire which is enshrined in several museums. A resurgent home wind turbine industry is now producing many readily available off-the-shelf models. Even Amazon is selling three models (400, 900W and 1.8 kW) ranging from $800 to $5,500.
The obvious place to start researching is the Web where a wealth of information exists about how to start, the economics, costs, location, electrical work/wiring and wind dynamics. One unit I am investigating is Southwest’s Wind Power’s SkyStream 3.7, a self-contained unit with an inverter to get on the grid. Southwest claims to have sold 100,000 wind turbines so far and, often, reading through the online owner’s manual is as good a primer as any. But there’s any number of primers for intrepid experimenters and implementers. That said, I have also ordered Paul Gipe’s book “Wind Energy Basics,” which is considered something of a bible for wind power newbies.
Moving up the power curve, you’ll find Bergey and Aeromag, two other established wind turbine manufacturers. A 100-ft or higher tower with a turbine producing all your electricity — the typical home uses between 600-2000 kW-hr per month and averages about 940 — can easily burn through $50,000. Based in Norman, OK, Bergey offers packages, the most expensive of which is a 7.5 kW home system for $56,000 and that doesn’t include permitting and other ancillary costs that can run as high as $20,000. But that’s the home version Cadillac. You can experiment for as little as $1,500 and do very well spending around $10,000-$15,000.
Bergey’s website is packed with information that includes pricing. Founder Karl Bergey, a MIT and Penn State-trained aeronautical engineer, was a key developer of the Piper Cherokee airplane. Who better to understand propeller and wind dynamics?
For my backyard, I’m guessing anything higher than 40 ft might get nixed by the zoning folks. Checking local zoning ordinances for height restrictions, setbacks and other rules is a crucial first step, but siting is vital to the health of a wind turbine and harnessing the maximum energy. Consulting a wind map for local wind speeds or installing an anemometer to track them is important. How does the PURPA law work in crediting me for the power I produce? What’s the “avoided cost” rate that utilities pay? How do I get on the grid? Do I go with batteries? What are the economics? Where do I site the unit on my land? Are there area electricians who understand this technology? Should I consider a hybrid solar and wind turbine system for when the sun shines and the wind doesn’t blow which is common in summer.
This should be a fun and exciting journey. Understand that I am willing to lay down a few thousand dollars even if I do not achieve payback within a year or three. Thereafter, payback will be something I will track closely. Hopefully, my kids can get along without books, a dorm room and board for three or four college semesters. If you’ve installed (or built) a wind turbine already, I would love to hear from you. Write me at firstname.lastname@example.org or visit my blog Design Engineering at Large.