The new Carlsbad power plant will replace the Encina Power Station with a smaller, lower building. Jan 24, 2017. Megan Wood, inewsource.
The new Carlsbad power plant will replace the Encina Power Station with a smaller, lower building. Jan 24, 2017. Megan Wood, inewsource.

A long planned gas-fired power station in Carlsbad that squeaked through approval largely because it was the only source that could be up and running by the end of 2017 will not be complete by that date after all.

[one_half][box type=”shadow this-matters”]Large natural gas assets like power plants are built to last. The decision to place a new one in Carlsbad has impact long into the future, and many residents opposed it.[/box][/one_half]

David Knox, communications director with plant owner NRG Energy, confirmed construction has not begun and the powerhouse won’t be complete until the end of 2018, or later if there are further legal appeals.

An inewsource examination of utility filings has also found the new plant will be much dirtier than its original design. A design change to make the plant run at peak times rather than constantly will cause greater greenhouse and other pollutant emissions, hour for hour.

An array of clean energy businesses and environmental groups opposed the fossil fuel plant. The delay could give them another opportunity.

“It does mean we can continue to fight for a while,” said attorney Mike Levin of San Juan Capistrano, director of government affairs for Fuel Cell Energy, a clean energy provider. Opponents will continue lobbying the California Public Utilities Commission and state legislators, he said.

The renewable energy groups had argued it is too late to build another power station that runs on a carbon fuel in California. The state has committed to reducing carbon emissions 40 percent below 1990 levels by 2030. They say that means no new natural gas units can be constructed.

Making electricity is the second largest source of greenhouse gases in San Diego County.

The deal between NRG and San Diego Gas & Electric was also contentious because it was struck without competitive bidding. Some would-be bidders who had cleaner offerings were incensed at being sidelined by what they saw as a manufactured urgency for an end of 2017 deadline. John Leslie of Shell Energy North America LP wrote in a filing that it was “a convenient excuse for SDG&E not to consider other least-cost best-fit resources,” to meet regional need.

But NRG and SDG&E argued, citing analysis from the California Independent System Operator, that in the event of unusually high demand coinciding with the downing of two transmission lines — a planning scenario — there could be a critical shortage of electricity as soon as 2018. Only the new Carlsbad 558-megawatt plant could be ready by then, they said.

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In an unusual instance of state courts reviewing a public utilities decision, the 1st District Court of Appeal agreed last December with the Public Utilities Commission that approval of the 20-year power purchase agreement between NRG and SDG&E was reasonable.

Levin said originally he was stunned that the region’s needs would be met by burning more gas.

“You got a whole bunch of San Diego companies and Orange County companies — people who go home and pay their electric bills to SDG&E — and we all know that our technologies could be part of the solution. But we are really not being given the opportunity to compete on a level playing field,” he said.

Several energy experts have said the Carlsbad Energy Center will be one of a handful of new gas burning units that are the last of their kind built in Southern California.

NRG Energy will tear down the steadfast Encina steam boilers and the smokestack that’s been a landmark for coastal commuters along Interstate 5 for decades. Taking its place will be a new, lower building, about three football fields inland. Since it will be built in the depressions of former oil tanks, it will be mostly below ground.

A 3D image of the southern part of Agua Hedionda lagoon. The left foreground show the former oil tank depressions where the new power plant will be built. Google maps.
A 3D image of the southern part of Agua Hedionda lagoon. The left foreground show the former oil tank depressions where the new power plant will be built. Google maps.

But a funny thing had happened on the way to final approval. Engineers changed the plant design to one that will be both more flexible, and more polluting, hour for hour, than the original approved design.

Hourly pollution rates when the plant is running full bore will be higher “for all pollutants,” according to the staff assessment by the California Public Utilities Commission. It will release 25 percent more greenhouse gases per hour than its original design, 15 pounds more smog-forming oxides of nitrogen per hour and 6 pounds more fine particles than the public was originally told.

“I wasn’t even aware they had done that,” said Tom English, an environmental and electrical engineer who lives in Carlsbad and tracked the issue. But he said the per-hour emissions increase isn’t the point.

“The big picture is they should not be putting in a gas plant in California if they have any intention of meeting their greenhouse gas goals. It goes in the opposite direction. It is a giant mistake,” English said.

Ironically, the design change is partly a response to San Diego County’s increasingly green mix of electricity.

Environmental engineer Tom English on the beach in Carlsbad. Jan 24, 2016. Megan Wood, inewsource.
Environmental engineer Tom English on the beach in Carlsbad. Jan 24, 2016. Megan Wood, inewsource.

The original idea was to build something that would run much of the time — base load power. But such power stations, which use technology known as combined cycle, don’t like to be turned on and off frequently.

So NRG asked authorities for a change to a design that could fire up and turn off frequently, cycling on and off before the sun rises and again when it goes down. Additionally, each of its five 100-megawatt units can operate independently.

“You need 100 megawatts? Flip one switch, you need 200, flip two switches, if you need all 500, flip five switches and you bring them all on,” Knox said.

Southern Californians’ demand for power shows just how useful that is. Some afternoons and evenings demand can rise astronomically — 80 additional megawatts per minute, as people come home from work and school, Knox said. It’s a level of demand he does not believe can be met by renewables.

He points out NRG is not only in the business of building natural gas plants, but invests in renewables as well, with projects in solar, wind and storage.

So the Carlsbad Energy Center morphed into a peaker plant, albeit a large one. Peaker plants usually employ a technology called simple cycle. Simple cycle pollutes more than the combined cycle of base load electric stations.

Experts say peaker plants are usually the most expensive, dirtiest electrons we generate.

Jim Robo, CEO of the energy firm NextEra, predicted at a conference in 2015 that there may be no more gas-fired peaker plants built after 2020. Cleaner, cheaper, more easily deployed alternatives are proliferating.

Some locales are installing batteries instead of peakers. Other forms of electricity storage are burgeoning.

Entrepreneurs are even bundling promises as a form of energy. Homeowners can commit to delay washing laundry and dishes during hours of high demand and get paid for it. The saved power is promised as available to the utility company.

The Carlsbad power plant also goes in at a time when demand for electricity has flattened, thanks to conservation and to more efficient buildings and appliances. It is also because a growing number of homeowners and businesses have installed rooftop solar so they don’t draw as much power off the grid. Rooftop panels now feed more than 650 megawatts into the grid locally. This has forced forecasters to lower their predictions for overall electricity demand.

This is part of why, at one point in the process, an administrative law judge and the California Public Utilities Commission Office of Ratepayers Advocates rejected the proposed gas power plant. Administrative law judge Hallie Yacknin said that San Diego Gas & Electric had not sought out “preferred” or cleaner energy first, which would have shown whether  a large new gas plant was the best buy.

She said the Carlsbad Energy Center would “categorically preclude” renewables and other clean alternatives such as battery storage and demand reduction “beyond the minimum.”

But Stephanie Donovan at San Diego Gas & Electric said it’s a mistake to think building the large plant edges out cleaner electricity.

“The Carlsbad project doesn’t compete with renewable generation; it actually enables it – by filling in the ‘gaps’ of the variable (intermittent) renewable power and smoothing out the overall energy flow,” she wrote in email. “In the middle of the day, solar provides 50 percent or more of the power available for our customers, but when demand on our system peaks in the early evening, solar is not available.”

She called the new plant a workhorse for the region.

Ingrid Lobet is a reporter at inewsource specializing in the environment. To contact her with tips, suggestions or corrections, please email