April 8, 2005

Calpine prepares to fire up new Metcalf Energy Center

Company addresses operations concerns, environmental effects

By Shari Kaplan
Staff writer

“First fire.”

It’s the term a power-generating utility uses to describe the first time the turbines are turned on at a new power plant.

And while it’s not open to the general public like a restaurant ribbon cutting, it will soon be happening in San Jose’s own backyard.

The Metcalf Energy Center is a 600-megawatt combined-cycle power plant situated on 20 acres in South San Jose’s Coyote Valley area. Photograph courtesy of Calpine.

First fire is expected to take place before the end of April at the Metcalf Energy Center (MEC) in Coyote Valley, a 600-megawatt power plant located on approximately 20 acres along Monterey Highway south of Metcalf Road. Its parent company, Calpine, will then fine-tune the systems before June 2005, when the company expects full commercial operation to commence.

On average, according to MEC public and community relations manager Lisa Poelle, one megawatt can power up to 1,000 households, which means the MEC is capable of powering up to 600,000 homes at any given time. This will be especially valuable, she said, when the planned urban development in Coyote Valley is built in the next few years.

Looked at another way, 600 megawatts is enough to power eight million 75-watt lightbulbs, six million 27-inch televisions or 2.8 million personal computers.

How combined-cycle works
Calpine is a mega-utility that operates more than 90 power plants in the United States, Canada and the United Kingdom, with another under construction in Mexico. Founded 20 years ago in California, Calpine built the majority of its plants—currently 39—in its home state, where it generates nearly 4,000 megawatts of electrical power by way of technology called combined-cycle generation. It sounds high-tech, but it’s actually quite mechanical, according to Calpine literature that puts the process in layman’s terms.

In combined-cycle generation, clean-burning natural gas produces two forms of energy: electricity and steam. Gas-fired combustion turbines spin generators, which creates electricity on one end and heat on the other.

The electricity is harnessed and routed through electrical switching centers and substations, and from there goes across power lines to serve cities near and far. In MEC’s case, its electricity goes to the adjacent Coyote Valley Switching Center, and from there to PG&E’s Metcalf and Monte Vista substations.

The heat by-product of the gas-driven turbines is sent to the plant’s heat recovery steam generator, where steam forms and is quickly directed to a steam turbine, which in turn spins another generator. That generator produces additional electricity. The natural gas comes in through an underground pipeline Calpine built to connect with an existing PG&E gas transmission line running along Highway 101. The construction followed all federal and state safety standards.

Addressing concerns
Poelle says Calpine has worked to assuage the concerns of some South San Jose residents before the first fire, as members of the Santa Teresa Citizen Action Group (STCAG) had questioned the company and the City last year about the plant’s air quality monitoring and the need for a power plant in the area at all.

Elizabeth Cord, a Santa Teresa resident and STCAG co-founder, said even if the plant keeps its emissions to a minimum, it’s located in the wrong topographic area. Between the steep hills and mountains of the Coyote and Santa Clara Valleys and the marine inversion layer of cool air coming from the coast, valley air is often trapped for days. When this happens, it becomes progressively smoggy as well.

“It [MEC] may be a nice, clean plant as Calpine says, but it shouldn’t be in a valley that doesn’t have clean air circulation. I remember a professor from the Naval Post-Graduate School in Monterey commented that having a power plant there [in Coyote Valley] is like smoking in a closet,” Cord said.

“And it will be the biggest source of emissions in the city of San Jose. As such, that’s a concern,” she continued. “Cars are something we kind of have to have, but power plants don’t really have to be so close to a million people’s homes.

Most power plants I know of are located in remote places like deserts, or along the coast where the air isn’t trapped.”
In speaking of coastal power plants, Cord said she feels the 2,538-megawatt Moss Landing plant in Monterey County is sufficient to power the Santa Clara Valley, especially since the “energy crisis” of recent years past was not so much of a crisis after all.

“We’re also concerned about the tanker trucks that will be driving down Monterey Road delivering ammonia to the plant. That’s flammable stuff!” Cord said, referring to the chemical mixed in low percentages with the water used in the MEC’s combined-cycle power generation.

The MEC, like all power plants of its kind, will emit—among other things—carbon monoxide (CO), nitrogen oxides (NOx, a precursor to smog) and tiny bits of dust and soot called “PM10,” which stands for “particulate matter” with diameters of 10 microns or greater. A micron is one-thousandth of a millimeter.

Poelle said she understands why citizens may be alarmed when they hear statistics about MEC emissions. For example, the maximum amount of NOx the MEC may generate is 124 tons per year, and the maximum PM10 is 91 tons per year.

These numbers seem large, Poelle said, until they stand beside figures provided by the Bay Area Air Quality Management District (BAAQMD). For example, the number of cars in a city not even as large as San Jose generate over 7,800 tons of NOx per year, whereas the MEC will generate 124. As for PM10, it’s currently present in Santa Clara County air at levels of 18,000 tons per year. Poelle understands people’s concern about a power plant adding more to the mix, and agrees the current tonnage is alarming, but explained that MEC’s addition is less than one-half of one percent of that amount.

“In bringing new power plants online, the air quality should actually improve, because the older, less efficient power plants are not called upon as frequently,” she said.

Compared to the average standard fossil-fueled power plant, combined-cycle plants like MEC emit, on a megawatt-hour basis, approximately 96 percent less NOx, a major cause of smog; nearly 100 percent less sulfur dioxide, a major cause of acid rain; about 53 percent less carbon dioxide and almost 84 percent less particulate matter. And, unlike coal-fired plants, combined-cycle plants have no mercury emissions—a major health hazard.

Safety and scrutiny
“Calpine is well-known for operating environmentally safe and responsible plants,” added Poelle, citing that both the Loma Prieta Chapter of the Sierra Club and the Santa Clara-San Benito County Chapter of the American Lung Association have published letters of support for MEC. “We gave them tours and lots of data. They did their own research and were very thorough in studying how a combined-cycle generation plant works,” she said of the two Bay Area nonprofits.

“These projects go through a lot of scrutiny,” Poelle stated, citing 29 reviews by individual experts and civic entities and 50 public meetings that transpired between 1999 and 2002, before Calpine could even lay a foundation for the MEC.

In late March, Poelle told the Times that MEC has already received unanimous approval of its amended air permit from the California Energy Commission, and is awaiting approval from the BAAQMD, which should come by the first week in April.

The air permit to which she refers is officially called “Petition to Amend Air Quality Conditions” and will slightly alter some existing permit conditions related to startup, shutdown, turbine combustor tuning and commissioning. The amendment does not contain requests to revise any of the MEC’s particulate matter or sulfur dioxide emissions, nor would it cause MEC to exceed its allowed emissions of gaseous pollutants like carbon dioxide, nitrogen oxides or ozone.

The MEC will constantly analyze its emissions on-site, Poelle said, and regularly report its figures to the BAAQMD. Due to public concern, Calpine also made an agreement with the city of San Jose to install a temporary air quality monitoring station in Santa Teresa’s Los Paseos Park, which will establish what the area’s ambient levels of CO, NOx and PM10 are. It has been in place since November 2004. When the plant fires up commercially, the station will continue with its daily monitoring of these emissions.

Additionally, Poelle says, Calpine is waiting for the city of San Jose to find a location to install a second air quality monitoring station at the southern end of Coyote Valley, closer to Morgan Hill. That way, both the northern and southern municipalities bordering the valley will be covered. These monitoring stations are in addition to existing stations already located in the Santa Clara Valley, where Calpine has several other combined-cycle plants. The southern station will be permanent; the Los Paseos Park station will operate only until the City finds a permanent northern-end location.

“While these air monitoring stations are not required by state and local regulatory agencies, Calpine has consistently gone above and beyond in our efforts to provide further reassurance to South San Jose residents,” said Mike Argentine, Calpine director of development.

Another safety-conscious feature of the MEC, according to Poelle, are the stringent seismic safety codes followed in the plant’s construction, since there’s no telling when an earthquake might strike. One such safety measure is a foundation that was pile-driven and poured to 60 feet deep, to keep the structure as stable as possible during a temblor.

On the conservation front, Calpine purchased 116 acres on adjacent Tulare Hill, which it then donated to the Santa Clara County Land Trust and will maintain as an ecological preserve. It also has set aside 15 additional acres for habitat preservation on nearby Coyote Ridge. Additionally, the company has donated $50,000 to Our City Forest, a local nonprofit whose volunteers plant and tend hundreds of street and shade trees each year in the greater San Jose area. Trees, especially in large numbers, are effective at absorbing carbon dioxide and other pollutants and returning breathable oxygen into the air.

For more information about the Metcalf Energy Center, visit www.metcalfenergycenter.com on the Internet or call (408) 463-8008.