Wind Energy in Virginia

Europeans used wind energy to sail to Virginia for 400 years, from the 1500's into the 1900's. Since those Europeans settled Virginia successfully in 1607, rural Virginians have used windpower to pull water up from wells - long before electrical lines connected farms to the "grid" and powered modern pumps. In some cases, wind power was also harnessed in Virginia to power manufacturing facilities, such as mills that ground wheat into flour. Pumping and powering grist mills required that the windmill be located directly next to the facility - gears and belts could not transmit the mechanical energy more than about 100 feet.

farm windmill
Source: National Renewable Energy Laboratory Photographic Information eXchange

Today, almost all labor-saving devices in the home, office, or manufacturing plants operate off electricity that can be generated far away from the site where the power is used. A handful of existing wind turbines convert wind energy to electrical energy, including one 10 kW turbine at the Smith Mountain Lake Visitor Center:

Smith Mountain Lake windmill
Source: National Renewable Energy Laboratory Photographic Information eXchange

More wind-powered turbines are planned. Demand for more electricity is expected to increase along with the state's population, despite intermittent efforts to conserve energy. The one-time infrastructure costs of building turbines and electrical transmission lines in remote areas is high, but the annual cost for fuel (wind...) is free. In addition, states are adopting Renewable Portfolio Standards that mandate a certain percentage of electricity generated or purchased within the state come from renewable sources, and urban regions with air quality problems (like Metropolitan Washington) are trying to get credit for purchasing "green power" to meet Clean Air Act standards.

wind energy potential in Virginia
Source: Wind Energy Resource Atlas of the United States
(note the potential in Highland County)

The greatest potential for generating electricity from wind energy in Virginia is to locate turbines in the mountains (especially Highland County) and offshore (east of the Eastern Shore/Virginia Beach). Utilities seeking to generate electricity for sale look for at least Class 3 or higher zones, where wind speeds exceed 7 mph.

Windmills involve tall towers, so the projects involve scenic impacts. Wind speed next to the ground is reduced by friction with vegetation and the surface of the ground. However, 400 feet above the ground, the wind currents will be faster and steadier. A tall windmill has greater potential to convert wind energy into electrical energy, but a tall windmill will also be more visible from a distance.

wind energy potential in Highland County, Virginia
Source: Virginia Wind Energy Collaborative: Virginia Wind Resource Map with VWEC Activities
Wind power density at 50 meters

Ridgetops in the Blue Ridge, Ridge and Valley, and Appalachian Plateau physiographic provinces - and the open water region off the Outer Continental Shelf - are clearly the areas with Class 3 and higher winds that could power a modern turbine. Raising the turbine above the trees on towers 150-400 feet tall increases the potential windpower that could be captured... but makes the turbines very obvious intrusions on top of forested mountain ridges. In addition, new transmission lines will require cutting new swaths through the forests, creating visual scars.

transmission lines in Highland County, Virginia
see any major transmission lines in Highland County, Virginia?
Source: National Renewable Energy Laboratory -
United States Annual Wind Resource Potential

The Virginia Wind Resource Map1 summarizes the wind potential of the state at 50 meters above the ground:
Several areas of the state are estimated to have good-to-excellent wind resource. These include the Atlantic coast along the Delmarva Peninsula and the Virginia Beach area, the ridge crests in the north-central part of the state, and ridge crests near the borders of West Virginia and North Carolina.

Offshore locations are atttractive locations because there are no forests, no trees to slow down the breeze. From a venture capitalist point of view, the ownership and permitting issues are also significant. Turbines are not cheap, and "time is money," so investors look for places where the delays in getting authorization to build will be minimized. Wind energy projects can be located according to financial and political reasons, as well as by simple physical geography.

There are no private landowners offshore, no land to lease or buy. Instead, Federal permits must be obtained from the Department of the Interior - Mineral Management Service. Previously the Corps of Engineers issued the permits, in order to manage the creation of new obstructions to navigation. Now MMS has the responsibility, reflecting their offshore responsibilities for oil and gas drilling and mining from the ocean seafloor.

Federal permits require an environmental analysis and a public comment process. The request for a Federal permit near Nantucket Island in Massachusetts became a hot political issue in 2005-2006, and the US Congress slowed down the proposed offshore wind farm there.

On land, the mountains of Virginia are the most attractive locations for electricity-producing wind tubines. Mountains channel the wind currents into gaps, and wind speed on the ridges is usually higher than in the valleys. Because the jet stream typically flows north of Virginia, windmills are feasible on low ridges in the northern part of the state. The closer to the North Carolina border, the higher the Virginia ridge must be to intercept strong and steady winds.2

Generally speaking, the elevation at which the mountaintop wind resource becomes attractive for wind projects increases from about 400 m (1300 ft) in the north to about 1100 m (3600 ft) in the south. This trend reflects the decrease in winds aloft as one moves south of the main path of the jet stream. An exception to the pattern may be the mountains at the outlet of the Roanoake valley, such as Roanoake Mountain and Windy Gap, which at a height of 500-800 m (1600-2600 ft) are well below the elevation that would be expected to have good winds in this part of the state. The valley appears to form a channel for winds flowing out of the mountains. That channeling effect is predicted to increase the wind resource on exposed high points within and just outside the valley.

Most wind energy projects in the mountains are located on private lands. Energy companies would rather pay a private landowner and go through a county planning process than request a permit from the USDA-Forest Service to place turbines on Federal lands. (In addition, wind energy projects intended to generate power for sale must get a certificate from the State Corporation Commission.)

wind energy potential in Virginia
would you buy stock in an energy company (or support an environmental organization) that planned to generate wind power along the Fall Line?
Source: Landscape Classification System For Virginia

In November, 2002, Winergy LLC proposed to build 271 wind turbines in the Atlantic Ocean, east of Accomack County at a site called Porpoise Banks 2. The company proposed to build enough turbines to generate 975 megawatts/hour, equivalent to the output from a nuclear power plant. When the Army Corps of Engineers advised that the location was sensitive to the military, Winergy shifted its area of interest to the ocean east of Smith Island, at the southern tip of the Eastern Shore.

Winergy proposed to locate the turbines three miles offshore, putting the structures in Federally-controlled waters 60 feet deep and spread out over 45 square miles. Winergy's primary interest was getting the authority, establishing a valuable permit that had passed through the legal and political process:
“Basically, we’re nothing more than real estate developers,” said Robert Link, one of two principals who make up Winergy, which hopes to sell many of the permits it receives to power companies. “We’re dealing with the zoning of the ocean.”3

However, all proposals for wind farms offshore from the Virginia coast remain just proposals, with no operating turbines. Locating turbines out of sight, offshore of the Atlantic coastline of Virginia, does not eliminate siting conflicts.

In addition to the constraints of finding a location in Virginia with sufficient energy to power turbines, two environmental constraints limit the potential location of new wind energy farms - the visual impacts of the towers and blades, and tendency of the blades to kill birds and bats migrating through the area.

Turbines could be "bird Cuisinarts." The Eastern Shore is a major stopping point on the Atlantic Flyway, and the Army Corps of Engineers must consider the potential impact on migratory birds before granting a permit for an offshore wind farm.

A proposal in 2005 to build turbines on a ridge in Highland County exposed the conflicts between tourism-based businesses and the those who support wind farms. One article in the local paper noted that Federal mandates for utilities to generate a certain percentage of their electricity from renewable sources (renewable portfolio standards or "RPS") would stimulate wind power projects, but some states are "wind poor."

Even within a state that has the climate and topography to generate a lot of wind energy, the locations for windmills are often in rural areas - requiring unsightly power lines to the urban areas creating the demand for power. As discussed in the Congressional debate:
Proponents of a mandatory RPS say, Just buy wind power from wind generators in other states. Sounds easy enough, but how do we get that power to the state? Wind turbines obviously have to be built where the wind is. These locations are usually remote and far from our cities where the electricity is most needed. In most every instance, there is insufficient transmission capacity to move that power to where it is needed.4

In early 2006, Community Energy, Inc. revealed its interest in building a wind farm in Patrick County. As described in The Roanoke Times:5

The company is looking at ridges around the county, but it has focused largely on Belcher Mountain, near Meadows of Dan, and Bull Mountain, near Patrick Springs.

Officials expect the turbines would be comparable in size to those proposed in Highland, which, if built, would stand slightly taller than Roanoke's Wachovia Tower.

The project will require approval from state and federal agencies, but because Patrick County has no zoning ordinance, the county's say extends only to whether it grants the company a building permit.

On Monday, however, the Patrick County Board of Supervisors voted 3-2 to pass an emergency ordinance that would prohibit the construction of any structure more than 100 feet in height...

Geographic Information System (GIS) technology can be used to identify environmentally-sensitive locations that would stimulate objections to a proposed wind energy "farm" of multiple turbines - see A Landscape Classification System for Virginia. Here is a sample map from that report:

buffer zones of environmentally sensitive areas and Class 3 wind zones
buffer zones drawn around sensitive environmental areas to identify Class 3 wind areas that may be more/less suitable for turbine locations
Source: Landscape Classification System For Virginia

Links

References

1. Department of Energy - Wind Program and the National Renewable Energy Laboratory, "Virginia Wind Resource Map," www.eere.energy.gov/windandhydro/windpoweringamerica/maps_template.asp?stateab=va (last checked June 11, 2006)
2. Brower, Michael, Wind Resource Maps of Virginia, p.2, 2002, vwec.cisat.jmu.edu/documents/Virginia%20Wind%20Mapping%20Report.pdf (last checked June 11, 2006)
3. Alliance for the Chesapeake Bay, Chesapeake Bay Journal, "Wind turbine proposals for Atlantic Coast face challenges," January/February 2003, www.bayjournal.com/article.cfm?article=727(last checked June 11, 2006)
4. The Recorder, "Congress takes up debate on wind energy," June 23, 2005 www.therecorderonline.com/index.php?id=145 (last checked June 11, 2006)
5. "Wind may be asset in Patrick County," Roakone Times, April 14 2006, www.roanoke.com/news/roanoke/wb/xp-60907 (last checked June 11, 2006)


Energy in Virginia
Geography of Virginia