Everything You’ve Wanted to Know About Wind Power
- By: Joshua F. Moore
Q: How many wind turbines do we have in Maine?
That depends: What day is it? Reed & Reed, the Woolwich-based contractor who has so far built all the large-scale wind-power projects in Maine, can assemble the three pieces of a 262-foot-tall steel tower and attach the three 151-foot-long fiberglass or carbon-fiber blades in a single day. The components come from as far away as Vietnam and as near as Florida and the Midwest. The company is putting up the forty turbines at its latest project, the Rollins Wind Farm in Lincoln, as quickly as the weather will allow (it has to be dead calm, for obvious reasons) and CEO Jack Parker says his crews plan to finish sometime in June. But as of January 15, 2011, Maine had 133 turbines producing 265.5 megawatts of power in Mars Hill, Danforth, Freedom, Kibby Township, and Vinalhaven.
A megawatt is a million watts, the units used to measure electricity. But since this blast only quantifies a split second of electricity and fails to consider actual consumption, most people speak of megawatt or kilowatt (a thousand watts) hours, meaning the amount of power used over an hour. Maine’s residential electricity consumption rate is among the lowest in the country — just 3,433 kilowatt hours per home per year, thanks largely to our lack of air-conditioning units, according to a 2005 U.S. Department of Energy report. Each of the thirty-eight-turbines in the Stetson wind farm near Danforth produced 4,115 megawatt hours of electricity last year — meaning that collectively the project produced enough power for 44,000 homes.
Q: How many other wind projects are in the works?
Again, what day is it? An eleven-turbine expansion of the Kibby project was approved by the Land Use Regulation Commission in late December. Two wind farms, a twenty-two-turbine one in Roxbury and a thirty-four-turbine project in Oakfield, have been approved but are on hold while appeals are heard. Seven others have applications pending. In addition, companies such as Iberdrola and First Wind have erected weather towers in several locations around Maine — the first step in determining the feasibility of a wind farm.
Q: Why the gold rush?
We can’t blame it all on the Saudis. Granted, the price of a gallon of gasoline hit record prices in April 2008, when the Maine legislature passed an emergency measure to expedite grid-scale wind-power projects. But awareness regionally and nationally has also been increasing about the need to move to more renewable energy sources, and advances in technology have made wind turbines effective at lower elevations. Maine’s law, LD 2283, made wind power a “permitted use” within certain parts of Maine’s unorganized territories and streamlined the application procedure to encourage large-scale development within pre-defined areas. Regardless of the motivation, Maine’s wind-power law has had the desired effect: Where just four wind-power-project applications were filed before 2008, twenty-five have been proposed in the past three years.
Q: How much electricity does the law call for Maine to produce from wind power?
It sets a goal of two thousand megawatts of capacity by 2015 and three thousand megawatts by 2020, of which three hundred megawatts can be from offshore wind turbines. By comparison, Maine uses about twelve gigawatts annually to power itself, so the Natural Resources Council of Maine calculates that if the state reaches those goals, wind power could serve almost three-quarters of its current electricity consumption. To meet the state’s goals, developers will need to add 434 megawatts of electricity — nearly double the state’s existing wind-power capacity — each of the next four years. And the pace has to quicken with each passing day that a wind turbine doesn’t go up. Just a year ago, John Kerry, director of the Maine Office of Energy Independence and Security, put the necessary rate at 183 megawatts installed annually, a goal the state failed to meet in 2010. Kerry would not respond to inquiries for this article.
Q: The wind-power law talks about “grid-scale” wind farms. How big are we talking?
Wind farms vary from the three-turbine projects in Freedom and Vinalhaven to the forty-four-turbine Kibby project, which will soon expand to fifty-five turbines total. (Most wind farm developers require a project to have a capacity of between thirty and fifty megawatts to be financially viable.) The actual footprint of each turbine is relatively small, about twenty-five-feet in diameter, anchored to bedrock. That foundation usually requires a clearing about 250-feet wide. But since each 262-foot-tall wind turbine tower has to be situated about a thousand feet apart, a forty-turbine wind farm might require a line of turbines eight miles long if they’re all set in a row, as along a hilltop. For access, crews usually cut about a twenty-foot-wide road to the first turbine, and then a thirty-two-foot-wide crane pass between the towers, though this is usually re-vegetated back to about sixteen feet wide after construction.
Q: Does the power produced by wind turbines actually power the houses around them?
Not exactly. The power produced by industrial wind farms is fed back into the “grid,” which is actually a network of eight thousand miles of high-voltage transmission lines connecting six New England states and 6.5 million homes and businesses. These lines carry the power from 350 sources, ranging from wind turbines to biomass plants to nuclear plants, to substations where it is “stepped down” in voltage and sent back to houses and businesses across local distribution lines. This all happens in a fraction of a second, so it’s not exactly accurate to say that the energy going into a lightbulb in Mars Hill was produced by the turbines nearby. The grid is more like a big pool of electricity, with power flowing into and out of it simultaneously.
Q: That doesn’t sound like it’s doing much to reduce Maine’s carbon footprint.
Embracing wind power means thinking regionally, or even globally, but acting locally, according to Pete Didisheim, advocacy director for the Natural Resources Council of Maine. Because Maine is a member of the six-state ISO-New England grid, any electricity we produce from wind power will reduce our reliance on fossil-fuel burning power plants that currently supply 52 percent of our power (the rest comes from renewable sources such as hydropower and biomass). A report completed by ISO-New England in December determined that if the New England grid could get 20 percent of its power from wind power — up from 0.2 percent today — that would reduce the region’s carbon footprint by 25 percent.
Average price of a 1.5-megawatt wind turbine
Q: Doesn’t all this development ruffle some feathers in the environmental community?
Yes and, surprisingly, no. A strong campaign against land-based wind-power development has been led by groups such as Friends of Maine’s Mountains and Friends of the Boundary Mountains, which has fought against wind farms such as the Kibby projects since the mid 1990s. The Citizens’ Task Force — Maine, for instance, points out that 2,700 megawatts of installed capacity would require 1,800 1.5 megawatt turbines, or a total of 360 miles of windmills. But leading conservation groups such as the Natural Resources Council of Maine and Maine Audubon have actually endorsed several wind-power projects, arguing that the impacts on the immediate environment are outweighed by the potential of wind power to reduce the region’s carbon footprint. (The Natural Resources Council of Maine was one of the sixteen members of the task force that came up with the wording for Maine’s wind-power law.)
Q: So modern wind turbines don’t kill birds?
Actually, they do — and bats, too. The post-construction study that was done in 2007 at the Mars Hill wind farm (all such projects are required to complete avian studies), for instance, found twenty-two birds and twenty-four bats that had been killed by the turbines. All of the birds were non-threatened songbirds, including Blackburnian warblers and golden-crowned kinglets, while the bat deaths included three species of special concern, the silver-haired bat, hoary bat, and eastern red bat. Though the monopole design of modern wind turbines prevents the nesting and bird deaths that were found at the country’s first wind farm, in California’s Altamont Pass, even wind-power proponents like the Natural Resources Council of Maine’s Pete Didisheim acknowledge that more wind turbines will mean more dead animals.
Q: Wind power is often cited as the solution to Maine’s unemployment woes. How many people does the industry actually employ?
Again, it depends what day it is. Reed & Reed has more than two hundred people, most of them Mainers, working at its Rollins site. When the project is completed in June that number will plummet, as most wind farms only have a dozen or so paid staff, though a handful of maintenance personnel might remain after construction to perform warranty and maintenance on the gears, hydraulic lines, filters, and three thousand other moving parts housed in the turbine’s nacelle, or hub. All together, the wind-power industry in Maine has involved about three hundred companies since 2005.
Number of 1.5-megawatt wind turbines required to be installed annually in Maine to meet legislative goals
Q: What makes Maine such a great place for wind farms?
Duh! It’s windy here. An American Wind Energy report estimated that Maine is windier than the rest of the New England states combined, and among the top twenty windiest states in the country. That’s largely because wind is stronger the higher you go, and Maine is blessed with 165 mountains higher than three thousand feet — the Promised Land for wind developers. The Governor’s Task Force on Wind Power Development that led to the creation of Maine’s wind-power law tried to protect as many of these mountains as possible, but it still left twelve such peaks above three thousand feet in the so-called “expedited” zone for wind development (15 percent of the nearly 140,000 acres above 2,700 feet is also fair game). Finally, Maine’s sheer size allows developers to put wind farms in remote locations, away from homes, although some neighbors in Mars Hill and Vinalhaven have complained about the noise and the psychological “flicker effect” of the blades.
Q: So would the ocean be the perfect place for wind turbines?
Out of sight, out of mind, right? Wind farms in the Gulf of Maine may end up dwarfing all the land-based projects [see page 61], with up to eight floating farms, each measuring eight square miles, producing a total of five thousand megawatts — as much as five nuclear power plants. But such projects are still in their early development, and no offshore turbines or even prototypes have yet been launched.
Life expectancy of a wind turbine. (though this varies greatly depending on maintenance)
Q: Won’t turbine blades ice up in the winter?
Not for long. Though some ice buildup has been known to happen if the rotors aren’t moving, the sun generally melts it relatively quickly. Plus, just rotating the blades slowly tends to fling off whatever may have accumulated, in which case remember to duck — a 151-foot-long blade can fling an icicle quite a distance!
Q: What about when the wind doesn’t blow?
Modern turbines, like the GE 1.5-megawatt ones installed at most of the wind farms in Maine, start producing when the wind is blowing just eight miles per hour and keep spinning until the wind is blowing fifty-five (the optimal conditions are about twenty miles per hour). But when the rotors aren’t turning at all or the turbines aren’t producing their full capacity — around 70 percent of the time, depending on location conditions — the grid must rely on other sources such as gas- and coal-fired power plants. Wind turbines aren’t alone in having downtime; most coal-fired power plants operate only up to 70 percent of their capacity due to scheduled outages and market conditions.
Q: How loud are wind turbines?
Depends who you ask. According to Maine Department of Environmental Protection rules, wind turbines must produce a sound less than forty-five decibels, depending on the existing ambient noise. Most wind-power proponents say the “whoosh” of a wind turbine sounds like a refrigerator humming or a highway a few hundred yards away. But people who live near turbines use far different language to describe the “sonic bombardment” they experience when the rotors are turning, likening the noise to a drumbeat or the roar of a jet engine.
Q: So how far away should the closest house be?
Half a mile, at minimum. But most agree that a mile is more advisable, as virtually no complaints have been lodged by neighbors this far from a wind turbine.
Q: So can Maine really become the “Saudi Arabia of Wind” as former governor Angus King and other wind-power entrepreneurs claim?
Texas and Iowa lead the U.S. in wind-power production, turning out 9,727 and 3,670 megawatts, respectively. In New England, Maine wind turbines are currently supplying the vast majority of the 290 megawatts of electricity currently flowing into the ISO-New England grid from wind resources. If Maine were to miraculously meet the goals set out in LD 2283 tomorrow, it would still only be the third-highest state for wind production, according to data included in the American Wind Energy Association’s third-quarter 2010 report. Such a ranking is unlikely; just as Maine is increasing its wind capacity, electricity production from wind resources across the U.S. is increasing about 30 percent annually. Internationally, the U.S. used to be the leader in wind-power development, although China has recently taken the lead by installing a whopping 16,000 megawatts of capacity last year — more than three times as much was installed in the U.S. in 2010.
- By: Joshua F. Moore