For the past four years, what most people in the Coachella Valley have heard about Competitive Power Ventures’ natural gas-fired Sentinel electric plant can be summed up in two words: Power and money.
The 800-megawatt peaker plant now under construction in North Palm Springs amid hundreds of windmills has been promoted as the answer to the valley’s need for extra power during its blistering summer days and for a supplement to its growing supplies of solar and wind energy.
The $900 million, privately funded project would power the desert economy as well, creating hundreds of jobs and generating millions of dollars in sales and property taxes for local coffers.
Then there’s the windfall $53 million coming to the region in mitigation fees CPV has paid to the South Coast Air Quality Management District to fund clean air initiatives.
“It’s important to note as well that by bringing a new facility like this one online, it enables us to put offline older, less efficient and more heavily polluting facilities,” said Assemblyman V. Manuel Pérez, the Coachella Democrat who wrote the law that created the mitigation fund.
But – as controversy grows over what kind of projects that money should be used for – what’s been missing from the equation are the hundreds of thousands of pounds of pollution and greenhouse gases the plant will pump into the valley’s air over its expected 30-year life-span.
As a peaker plant – able to run a maximum of 116 days a year once it begins operating next winter – Sentinel and its eight 90-foot-tall smokestacks could spew more than 1 million tons of carbon dioxide per year, according to the final approval from the California Energy Commission.
That’s the equivalent of adding 188,334 cars per year to the valley’s roads, using formulas from the Environmental Protection Agency.
The region already suffers from high pollution rates from smog, ozone and other emissions blown in from Los Angeles ports and carried east with about a million trucks that travel Interstate 10. The valley’s surrounding mountains, low elevations and strong winds further aggravate the problem.
In the American Lung Association’s annual air pollution rankings, Riverside County has received an “F” every year since 1999.
Regional air quality figures – using maximum, worst-case estimates – indicate emissions from Sentinel could push already-high pollution levels as much as 277 percent over annual state limits for particulate matter, the tiny particles from the plant’s combustion that can have major health impacts.
“Natural gas power plants are really PM facilities. They take natural gas and turn it into particulate matter, really small particulate matter,” said Angela Johnson Meszaros, attorney for California Communities Against Toxics, an L.A. nonprofit organization that has filed a series of lawsuits to stop the plant.
Sentinel supporters counter that the plant’s future pollution has already been offset by emission credits that CPV was required to buy from the air district – the source of the $53 million.
“The offsets represent emissions permanently erased from regional facilities permanently shut down or no longer emitting,” said Sam Atwood, spokesman for the Air Quality Management District.
“As growth occurs, air pollution increases; we’ve accomplished growth without that increase.”
The catch – and a point of the continuing litigation – is that CPV’s purchase of the offsets from the district represents a unique situation, the result of the law Pérez wrote to help the project overcome its legal obstacles.
The recent suit California Communities filed against the Environmental Protection Agency, AQMD and CPV is in the U.S. 9th District Court of Appeals. A hearing is likely between May and November, Johnson Meszaros said.
With concrete poured on the project site, and turbines and eight 90-foot-tall smokestacks waiting to be assembled and installed, such matters may seem a moot point. The litigation has yet to stop construction, and neither CPV nor AQMD officials expect it will.
Still, with $53 million on the table, balancing the plant’s economic benefits and public health impact might be a critical first step in deciding how to spend the money.
Michael Kleinman, a professor at University of California, Irvine’s School of Medicine, who has studied the health impact of air pollution, says the district’s use of offsets doesn’t guarantee clean air.
“If you look at it as a zero-sum game, if you’re reducing the total amount of pollution, it’s good for someone,” he said. “It’s not going to improve your air quality; it’s going to make the local air quality worse.”
“When you are talking about energy generation, you are always going to have tradeoffs,” Pérez agreed.
“There’s still going to be an impact to public health, and therefore it’s essential to accurately quantify those impacts and then aggressively work to mitigate them. That’s what the mitigation fund is for.”
Plant will help fill in several power gaps
The need for peaker plants such as Sentinel is undeniable and essential for maintaining California’s energy supplies, says Stephanie McCorkle, director of communications for the California Independent System Operator Corporation, which regulates power supplies for the grid statewide.
Beyond providing quick power at times of high demand, a peaker’s ability to fire up or shut down in minutes can smooth out uneven power flows on the grid resulting from new “smart” technology and the addition of wind and solar energy supplies. Integrating renewables is a high priority to meet California’s 33 percent renewable energy standards by 2020, she said.
The state also faces the possible loss of 12,000 megawatts of power due to a new rule on the water cooling of coastal power plants that may result in the retrofitting or closure of up to 11 of these facilities over the next five years.
“There’s more interaction on the grid for demand response; there are more dynamics. We’re seeing a historic shift in the electricity industry; we haven’t seen a change like this in 100 years,” McCorkle said.
“We’re trying to educate policy-makers about the need for flexible capacity. We’re not going to have as much hydro. Gas-fired generation is critical to reliability. The faster you can get power on the grid, the more valuable those megawatts will be.”
If run at maximum capacity, Sentinel’s eight natural gas turbines will produce enough electricity to power 640,000 homes, CPV spokesman Will Mitchell said.
The company has a 10-year contract to sell all of the power from the plant to Southern California Edison, and Mitchell expects that will keep Sentinel running at or near full capacity.
Edison officials confirmed the contract but said it’s not possible to know how often the plant will be online, how much of its power will be needed or whether it will be used in the Coachella Valley.
That will be determined by California ISO through competitive bidding on its spot market to ensure adequate power reserves.
“Power plant units bid in a day ahead and the day of to provide standby power in case we lose a power plant or demand suddenly skyrockets,” McCorkle said.
Fewer construction jobs created so far in valley
The plant also has delivered on local jobs, though not quite as many as promised.
CPV originally estimated Sentinel would take about 18 months to build and employ an average of 200 workers, with a peak of 370 by its sixth month.
Now almost halfway through construction, the project is running on schedule but has only 150 workers onsite, with about 120 coming from union hiring halls in Riverside and San Bernardino, said Mark McDaniels, manager for the project.
Expected job numbers for the project now top out at 250, Mitchell said.
Much of the work so far has been done by subcontractors, so day-to-day employment figures are hard to pin down, said Bill Perez, business manager for the Riverside & San Bernardino Counties Building and Construction Trades Council.
He estimated about 25 percent of the workers on-site are valley residents, with the balance coming from the Inland Empire. The percentage of valley workers should rise as the turbines and plants are built, he said.
Riverside County Supervisor John J. Benoit said the project’s contributions to the county’s budget will be helpful but modest – about $5.1 million in property taxes and $2.3 million in sales taxes.
The lower jobs numbers are predictable, Benoit said.
“When we get down to all these projects, they’re a little overoptimistic in their projections.”
Air studies still unclear on micro-particles
Natural gas is, undoubtedly, the cleanest burning of all fossil fuels, with greenhouse gas emissions about 43 percent less than coal and 30 percent less than oil, according to the Union of Concerned Scientists.
Sentinel’s eight GE turbines will use the best available technology for reducing and containing emissions – a process called selective catalytic reduction.
Particulate matter, called PM-10 and PM-2.5, is very small particles that result from the combustion of fossil fuels, including natural gas. PM-10 stands for particles of 10 microns or less; PM-2.5 is 2.5 microns or less. A micron is one-millionth of an inch.
The estimates for Sentinel have the plant pumping about 118,000 pounds of PM-10 into the air its first year of operation and an additional 112,000 pounds each year for the life of the plant.
A growing number of studies suggest there is no threshold below which these particulates don’t cause health problems.
More worrisome, and harder to quantify, are even smaller, ultrafine particles – under 2.5 microns – that natural gas plants also produce, Kleinman said.
“We’ve been doing studies in Riverside, Los Angeles and Orange County,” he said. “Exposure to ultra-fine particles contributes to a number of health effects. We’re finding effects on lungs, and ultra-fine particles contribute to heart disease.”
While Kleinman’s studies to date have been on animals, he and other researchers say the valley’s children, whose lungs are still developing, and older residents with preexisting heart or lung conditions, could be the most affected.
James Gauderman, a professor at the University of Southern California’s Keck School of Medicine, has tracked the connection between lung development and air pollution in children across Southern California for nearly 20 years.
In highly polluted areas, he’s found an average of 5 percent of children with abnormally low lung development – about 80 percent of normal growth, he said.
Gauderman has not included Coachella Valley children in his studies but he said, on top of regional air pollution from Interstate 10, “any new source of particulate matter would be of concern to children’s health.”
“These ultrafine particles contain a lot of chemicals that are generated during combustion, many of them are known to be mutagenic and carcinogenic,” he said.
Johnson Meszaros calls the ultra-fines the worst sort of pollution.
“This is not dust from a road,” she said. “These are ultra-fines that are going to embed themselves in your DNA; these are the products of incomplete combustion.”
Atwell says the Air Quality Management District does not have the power to set standards beyond monitoring compliance with federal or state clean air limits, but it is funding studies on ultrafine particles similar to Gauderman’s.
EPA officials said the agency’s standards for PM-2.5 also include ultra-fines.
More research on the particles is needed, Atwell said.
“There is a lot of concern,” he said. “Until you understand what’s harmful, you can’t figure out how to regulate them.”
Benoit’s view is more pragmatic.
“The truth of the matter is we still all like to use our refrigerators and flat-screen TVs,” he said. “People are willing to trade off a rational amount of pollution to get that power.”