What I Didn't Know About Wind Power

Monday night's wind energy class, presented by Michigan State Cooperative Extension, was packed with both information and audience. Although I have written about Michigan's Comprehensive Energy Package in brief, This was the first time I'd heard some of the nuts and bolts applications of the new laws. I had the distinct and exciting feeling of moving toward a hopeful energy future and it was wonderful to be sharing that future with a roomful of over 100 people. (There were also 30 people on the waiting list for the workshop, which will be repeated in January. Watch the Leelanau Extension website for details.)

I can't begin to cover the whole workshop, but here are some of the points that have got me thinking:

It's not just for hippies anymore. In Leelanau we've had neighbors using wind generators for decades now. They were usually "back to the land" types, ready to accept limits to their electricity use and able to tolerate outages that required an investment of their own time or money to resolve. Often people lived "off the grid"on sites so remote that the cost of erecting a tower, installing a windmill, batteries, and an inverter to change from AC to DC was still cheaper than stringing wires to the nearest utility pole. The new generation wind energy systems are designed to work "on the grid", feeding electricity into the same power lines that bring the rest of us power. The new systems require no extra inverters or batteries; the grid itself functions as the battery. The many windmills or solar panels plugged into the grid function as a lot of little power plants in this new system of "distributed generation". Many smaller generation sites result in more power being produced and used locally, lessening the strain and waste of moving large amounts of electricity from one region to another.

Michigan's laws have changed to favor home generated energy. Just three weeks ago our legislature signed a Comprehensive Energy Package, committing to meeting 10% of Michigan's energy from renewable sources needs by 2015. This is not just a matter of feeling "green". Right now Michigan imports almost all of our energy at a cost of some $20 billion per year. Producing more electricity by harvesting our own wind will allow more dollars to go to work building our state's economy.

The Comprehensive Energy Package changes the rules for "net-metering" or selling a wind or solar generating household's excess energy back to the utility. Under the old rules you bought power when you needed it at retail rates but you sold you excess power at wholesale rates, or roughly half of retail. Under the new rules, you can sell your excess electricity for the higher retail rate. Each net metering household gets two meters, one measuring what you use and one measuring what you produce. At the end of a billing period, if you have produced more than you used, you get a credit for the excess. Right now both Cherryland Electric and Consumers Energy, the two power companies who sent reps to speak at the workshop, have billing periods of about a month, but that could change in the future if they invest in more sophisticated metering systems that can charge different rates hourly or daily according to the real cost of electricity. As the rules stand now, you can carry credit forward from month to month, but not year to year, and you can't register a net-metering setup that is rated to produce more than your home currently uses. You would never have a negative electric bill, or even a zero electric bill, as there are base fees that must be paid by everyone. But your bill could be pretty darn cheap.

We can look forward to the cost of electricity going up slowly but surely. For years, residential electricity rates have been kept artificially low because they have been subsidized by business and industry paying higher rates. Michigan needs to encourage energy efficiency and avoid penalizing industry, so the residential subsidy is being gradually phased out.

While not part of the legislative initiative, I also think about the next generation of cars, the plug-in hybrids, and how they will increase our total need for electricity. A plug-in hybrid could also function as a storage device for excess electricity. You would recharge your car at night when your household energy use (or the utility's rates) was low.

With the cost of wind generators falling, the cost of electricity rising, and everything else so unstable, I suspect the next generation of wind aficionados will be people disgusted with the stock market and looking for a more predictable return on a $10K or $20K investment.

Size matters. A few days ago I posted a photo of Mariah Power's Windspire, a compact, vertical axis wind generator designed to provide about one quarter of a typical household's electricity while conforming to most neighborhoods' height and noise ordinances. (Mariah Power is of special interest to northern Michigan because their next generation Windspire will be manufactured in Manistee. Read more and watch a video about their design here.) The windspire' vertical axis design is also bird-friendly, addressing a concern for the many Leelanau residents who live near important bird migration paths.

But the laws of physics still apply. If you use a higher tower, you will be able to take advantage of faster winds. As wind speed increases linearly, the potential power increases exponentially. We may well find that taller towers supporting smaller generators will seem less intrusive. Another physics fact: the colder the temperature, the more energy in the wind, because cold air is denser.

Scale matters. My interest in this class was to learn more about zoning for wind energy. There were a few guys in the audience who make their living installing home-scale wind systems. They were adamant that zoning needs to consider home-scale wind and utility-scale wind as two different applications. One installer decried "cookie cutter zoning" that required him to "put a flashing light on top of a 40 foot tower." The last presenter of the evening was an attorney who advises on utility-scale wind leases. Because of the length of these leases and the expense involved in decommissioning an obsolete wind tower, local planners would be wise to require that any such projects include a performance bond or escrow arrangement to insure that today's wind farm is not the next generation's brownfield. Tomorrow I am attending the Council of Government's class on Zoning for Renewable Energy so I'll write more about zoning later.

Wind generation is an attractive option for utilities. Utility scale wind is less expensive to build from scratch than coal plants or nuclear plants. Wind energy is perhaps difficult to predict on a day-today basis, but in the long run the cost is less volatile than the cost of crude oil or natural gas. Even if we leave climate change out of the equation, wind seems destined to play a major role in our future because it is becoming affordable.