How much wind is too much?
Wind is not a silver bullet. It does, however, change the energy equation. By exactly how much will depend on a number of factors including among other things government's (state and federal) commitment to increasing our reliance on indigenous energy resources and mitigating climate change. If these rise to the top of the nation's priority list (as they should), wind will play a major role.
That raises the question of just how much wind energy the grid system can comfortably and reliably accommodate. That in turn depends upon among other things, the nation's commitment to modernizing (digitizing) the grid and investing in the development of storage technologies. (GW)
Debate flares over wind power in Texas
By Elizabeth Sounder
The Dallas Morning News
July 6, 2008
There is such a thing as too much wind power.
For electricity companies, predicting wind patterns is a new art.
The wind blows hardest before the sun comes up, when people aren't using much power. It tends to die down during the afternoon -- especially in the summer -- just when people demand more juice.
Solving each issue will cost money.
Wind developers say wind power is so cheap that the cost to accommodate it is negligible. Coal, nuclear and natural gas plant owners doubt it.
"As we add more and more wind, there are some uncertainties and some costs," said Thad Hill, head of Texas operations for NRG Energy, which operates coal, nuclear, gas and wind plants in Texas.
"The important thing is, when we decide how much wind is the right amount, that we make that decision understanding these costs," he said.
Paul Sadler, executive director of advocacy group the Wind Coalition, said wind must be accommodated fairly, and technology exists to do so.
"Integration of wind is not sending a man to the moon," he said. "It's just a matter of having the will to do it."
But how much wind is too much?
The answer depends on the extent to which a person is invested in wind power.
Ned Ross, director of regulatory affairs for FPL Energy, a Florida company investing in West Texas wind farms, says there's no such thing as too much wind.
Other wind advocates say 30 percent of Texas' power could be supplied by wind. The Department of Energy, citing the Bush administration's support of renewable energy, says the country could get 20 percent of its power from wind by 2030.
Major generation companies in Texas that operate coal and natural gas plants say 10 to 15 percent is about all the state could handle.
Right now, the 5,000 megawatts of wind power capacity on the Texas grid contribute 2.9 percent of supply.
ERCOT expects wind developers to boost capacity to 9,000 megawatts by the end of the year, and to as much as 15,000 megawatts in the next few years.
That's good news for the environment since wind doesn't pollute, emit greenhouse gases or use water for cooling. But at times, the grid just can't handle so much wind power.
"There's really not enough transmission to West Texas to carry 9,000 megawatts," said ERCOT's vice president of system operations, Kent Saathoff. "So we're going to have to curtail wind, you know, probably significantly below 9,000 megawatts" until transmission lines can be built.
The Public Utility Commission is in the process of designating new transmission lines between West Texas and North Texas, South Texas, and possibly Houston. Commissioners later this month will choose among four scenarios costing between $3 billion and $6.4 billion. Those costs would be passed along to consumers.
Operation issues
Even if regulators solve the transmission issue, it isn't easy integrating more wind power into the grid.
In February, wind in West Texas died unexpectedly, leaving ERCOT scrambling to get backup natural gas plants online to meet power demand. The scare prompted ERCOT to upgrade its wind forecasting system.
ERCOT pays some power plants to operate on standby, ready to begin producing power within minutes if needed. Accommodating the fickle wind means paying more plants to stand by, adding to the total cost of wholesale power.
Some electricity executives quietly worry that the cost and trouble of accommodating too much wind could discourage generators from continuing to operate backup natural gas plants. Older plants that can't fire up quickly aren't flexible enough to provide backup for wind. And generators might not build new, flexible natural gas plants if they have to compete with cheap wind power.
Natural gas plants are the most expensive types of plants to operate these days because of the high price of fuel. Wholesale power prices can spike to 10 or 20 cents per kilowatt-hour, even higher, on a hot afternoon as more natural gas plants turn on. Add up the cost of building and maintaining a wind farm, and the power costs about 5 cents per kilowatt-hour.
Phillip Oldham, a lawyer representing Texas Industrial Energy Consumers, said that's why he doubts the wind developers' theory that more wind means lower electricity prices. At a certain point, the grid will need fresh back-up natural gas generation, and consumers will have to pay for it.
Airing concerns
Lawyers representing nearly everyone in the power industry have been airing these concerns to the PUC during the past couple of years as commissioners consider wind transmission.
The concerns about wind often come from companies that operate coal, nuclear or natural gas plants. Wind developers say those guys are just afraid to compete with cheap wind power.
"They're overplaying it, trying to make it a big deal," said Mr. Ross of FPL Energy.
Energy Future Holdings, the state's largest power generation company, operates a lot of power plants in North Texas and zero wind farms. The company supports a transmission scenario that would pipe wind power not only to North Texas, but also to South Texas. This would prevent cheaper wind power from driving down power prices only in North Texas.
NRG Energy, Texas' No. 2 power generation company, operates largely in Houston and South Texas. They want a modest transmission scenario that takes wind power to North and Central Texas, not to their home region.
And the Texas Industrial Energy Consumers, which includes Exxon Mobil Corp., Valero Energy Corp., DuPont and other giant factories and refineries, prefers the smallest amount of transmission. Many giant industrials own their own power plants, and they don't want to pay to support wind power that they probably won't use.
Leading the way
The arguments against supporting too much wind are swaying PUC Chairman Barry Smitherman. Last month, he said he'd been leaning toward the scenario to build the largest amount of transmission, but after hearing arguments from various parties, he favors a more modest scenario.
The experience in Texas will be an example to the rest of the country. The Federal Energy Regulatory Commission will spend the next three years copying Texas' process of siting transmission lines to accommodate wind power in the West.
0 Comments:
Post a Comment
<< Home