As wind power booms, so do the challenges
May 24, 2010 - The Seattle Times
Along the ridge-top flanks of the Columbia River, hundreds upon hundreds of wind turbines rise from wheat fields and sagebrush.
On a blustery spring day, these turbines can crank out more than twice the power of the Northwest's sole nuclear power plant. Then, on hot days in the summer, when the winds go still, the output plunges.
The turbines represent perhaps the most dramatic change to the regional power-supply system since the construction of the Bonneville Dam launched the era of federal power.
Billions of dollars of investment during the past decade have created a wind-power corridor that stretches more than 170 miles along the Columbia in Eastern Washington and Oregon, vaulting the Northwest to the leading edge of national efforts to develop this renewable energy source.
But the fickle, roller-coaster nature of generating electricity from the wind is also placing large new strains on efforts to manage the regional power grid.
"It is the great economic and engineering challenge of our time, at least in this industry, to try to figure out how to make all this stuff work," said Steve Wright, administrator of the Bonneville Power Administration (BPA). "It's a thrilling ride. But if something goes wrong, we're the folks that people are going to look at. So we take this very seriously."
The BPA manages a regional power grid that, minute-by-minute, must match the flow of electricity surging through the system with power consumption. When wind power unexpectedly surges or drops below forecasts, the BPA must idle back or crank up hydroelectric production from a network of Columbia River dams in order to avoid blackouts or other power disruptions.
As the wind industry expands, the BPA has found it more difficult to even out all the surges and drop-offs in electrical power, and still meet other responsibilities that include spilling water to aid the passage of endangered salmon.
Not driven by demand
The Northwest wind industry, which currently is able to generate more than 2,700 megawatts of electricity during peak winds, is expected to more than double or triple in size by 2016.
But the explosive growth in wind power isn't based on forecasts of growing regional demand for power.
The expansion is driven by federal incentives that offer generous tax credits or stimulus grants to wind-power producers. In addition, state laws in Washington, Oregon and California require utilities to generate or purchase an increasing amount of their power from renewable resources other than hydro.
Four years ago, Washington voters passed an initiative that requires utilities to harness 15 percent of their power from these renewable sources by 2020.
"This is a shift from the way power plants were built in the past, when you would wait for demand to increase to the point that the new power was needed," said John Harrison, with the Northwest Power and Conservation Council. "Now, there's a line in the sand that's drawn, and you have to have these plants whether you need them or not."
Some Northwest utilities, such as Puget Sound Energy, which recently announced plans for a third wind farm, in Garfield County, have made major investments.
But nearly half the region's wind power is shipped to California, and that proportion is expected to grow in the years ahead, according to BPA. The power lines that head south already are close to capacity, creating questions about who will pay for new lines and where they might go.
Wind-power developers are optimistic these challenges can be overcome, and some chide BPA officials for excessive hand-wringing about the future.
"I think that the solutions will evolve over time ... and that renewable energy from the Pacific Northwest is a great export to California," said Gary Hardke, president of Cannon Power Group, a major developer of wind power in Klickitat County. Cannon expects to tap into $200 million in federal grants to help complete its more than $1 billion investment in Washington.
Others say BPA has good reason for concern.
"It's not as easy as the wind-power developers would like us to believe, and I think BPA has gotten a bad rap," said Jim Smith, general manager of Klickitat Public Utility District. "It has the responsibility for making sure we don't have a blackout, and that the costs of sending all that power south aren't borne by the Northwest ratepayers."
New income for farmers
Klickitat County is the epicenter of Washington's wind-power industry. Less than a decade ago, the county was reeling from the closure of an aluminum smelter that employed more than 700 people. Today, developers have built or obtained permits to erect or expand more than a dozen wind farms.
In the county, wind-farm construction has created hundreds of jobs. Turbine owners pay local landowners more than $10 million in annual lease fees, and wind projects currently generate about $3.5 million in property-tax revenue annually.
"Motels that didn't even have a no-vacancy sign have had to buy them, and farmers who have been struggling for years have a new base of income," said Mike Canon, Klickitat County's economic-development director. "There have been benefits across the board."
But winds that blow through the region are fickle.
They can vary tremendously, meaning that wind-powered turbines can go from operating at 5 percent of their generation capacity to 80 percent in a matter of hours, then slump back down to nothing. In a year, wind-powered turbines generate on average about a third of their power capacity.
Small gaps between forecasts and wind-power production are relatively easy for BPA dispatchers to handle; they can quickly increase or decrease the amount of hydro power produced by Columbia River dams. BPA then charges the wind operators for this service, which also is necessary to avoid power surges that, in a worst-case scenario, could cause blackouts.
But the bigger the wind industry grows, the bigger the potential for major gaps between forecasts and outputs.
And the more wind power that is sold, the more backup that is required from hydro or other power sources in case the forecasts fall short.
There are limits to hydropower's ability to balance out the system.
Dispatchers, for example, need to keep some water in reserve to ramp up hydropower for an unexpected shutdown of the regional nuclear power plant. They also are required by federal court order to divert some of the water over the dams to help improve salmon survival.
Several times in recent months, BPA has asked wind-power producers to throttle back production the grid couldn't absorb. Cutbacks are expected to be more frequent this summer because a small snowpack will reduce the amount of water in the Columbia available to back up the wind power.
"BPA is rapidly being pushed to the operational and economic margin by the severe ramps of the large and geographically concentrated wind fleet on our system," BPA special assistant J. Courtney Olive wrote this month to the Public Utilities Commission of the state of California.
To try to reduce the surprise swings in wind power, turbine operators and BPA officials are scrambling to improve forecasting. They are installing more measuring gauges and developing sophisticated computer programs to model the passage of wind through the Columbia River basin.
Even with these forecasting aids, short-term trends in wind remain difficult to predict.
But some general long-term trends are obvious. Typically, the wind is strongest in the spring, when regional power demands are relatively low. And the wind often dies off in peak demand periods when high-pressure systems create winter cold snaps or summer heat waves.
Currently, the wind farms don't have a way to store the power. In the years ahead, that might change.
Klickitat Public Utility District proposes to harness surplus electricity to pump water from a low reservoir along the river to a second one high in the hills. When the operators want to tap into that power, they could run the water downhill through a hydro turbine system.
It's an expensive plan, with a price tag estimated at $2 billion.
Wind-power developers say there are other, less-costly options for balancing out the power surges without tapping into the BPA hydro system. They could, for example, pay companies that operate gas turbines to crank up capacity when wind dies off, and also pay to have those gas turbines backed off when the wind is blowing.
"That kind of integrated system is found in other parts of the country, and we need to do it here," said Robert Kahn, the Seattle-based executive director of Northwest & Intermountain Power Producers Coalition.
Smart-grid technology under development could help consumers make better use of wind power. In periods of surplus, for example, this grid would signal water heaters and other appliances to use more power, or electric-car batteries to charge.
In the meantime, the swings in wind-power generation keep getting bigger as developers expand old projects and launch new ones.
On the Oregon side of the Columbia, the largest wind farm in the world -- a $2 billion project with 330 turbines -- is scheduled to begin operations in 2012. The farm will sell all that power to Southern Edison, a California utility.
Hal Bernton: 206-464-2581 or email@example.com
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