Old Carlsbad Power Plant’s Environmental Toll Will Persist
Fish and other sea life smashed against intake screens. Creatures too small for the screens, liquified. Polluted air.
The Encina Power Station on the northern San Diego County coast, with its massive ocean water intakes, takes these tolls. California regulators called them so serious, that short of an emergency, the plant should shut down by November.
But the Encina gas power plant, whose landmark stack was built in 1954, will probably keep running through next year.
The expressed need to close Encina played a key part in the decision by the California Public Utilities Commission to approve a new $2.2 billion, gas-fired power plant in Carlsbad — with no competitive bidding.
The commission, California Independent System Operator, San Diego Gas & Electric and plant operator NRG Energy all said that the contract had to be awarded to build the new Carlsbad plant because it was the only one that could be open by the time Encina was slated to close.
“It did feel very manufactured, in terms of the urgency,” said Matt Vespa, a senior attorney with the Sierra Club, which opposed the plant. No sooner had officials decided that new power generation was needed locally, he said, than “you blink an eye and San Diego has a bilateral, a private contract with no competition with Carlsbad for 600 megawatts.”
Proponents of the new power plant see it differently. The urgency, they said, came from the sudden loss of the San Onofre nuclear plant in 2012. More power had to come online quickly to preserve reliability.
Now, however, the Carlsbad power station will not be ready in time. NRG said the site has been prepared but construction not started as the company waits to see if there are more lawsuits.
In the years since San Onofre, near the Orange County line, went offline in a scandal involving faulty steam generators, no particular burden has fallen on the existing Encina plant. In the three years after San Onofre closed, Encina operated just 5 to 7 percent of the time.
Demand from electrical users has been flat. Rooftop solar has proliferated, and a new power plant opened up in Otay Mesa.
It is impossible to know what kind of electricity project might have won if there had been competition for least cost, best fit and cleanest power. But it is clear the new fossil fuel plant goes in at a time when new sources for electricity are burgeoning.
Even the head of the Public Utilities Commission conceded that San Diego Gas & Electric received “a robust number of offers” for clean energy in 2014 when it asked for 200 megawatts.
Batteries are a big part of the buzz. Kate McGinnis, market development director at AES Energy Storage, points out batteries beat all the competition in 2014 when Southern California Edison was looking for 100 megawatts of new power in Long Beach.
“All different types of energy were evaluated for the LA Basin area, and this 100-megawatt project, plus other storage projects from other developers, were chosen in head-to-head competition with gas plants and other types of energy.”
Southern California Edison went on to buy an additional 160 megawatts of battery storage there in 2014, for a total of 260. Now, three years later, more battery installations have gone in. Tesla, Greensmith and AES just brought 70 megawatts online in record time in the aftermath of the Aliso Canyon natural gas disaster in Los Angeles County. That includes a project for SDG&E in Escondido.
“I can tell you that large-scale storage is definitely available today,” said Janice Lin, executive director of the California Energy Storage Alliance. “Storage is definitely a great application for an alternative to gas peakers.”
The new plant in Carlsbad will be a peaker, that is, a power unit designed to turn on when demand is very high or when demand climbs swiftly. Then just as easily, it can turn off as the sun comes out. They also are dirtier than plants that constantly run, known as base load plants. A change in design converted the new Carlsbad plant from base load to peaker, as reported last month.
Renewable energy, such as solar or wind, is changing the very concept of a peaker plant. No longer are such units only needed on the hottest days when people crank up air conditioners. Now, something akin to a peaker plant is needed each day when the sun sets or the wind dies down.
Power companies say ‘not yet’
NRG does not agree it could have installed an array of batteries or other clean energy instead of gas-burning turbines on its property in Carlsbad.
“Battery storage is going to change the world. But the question is, when is it going to change the world?” asked Dave Knox, an NRG spokesman.
Battery storage is still too expensive, he said. Batteries take too long to charge, they do not provide power for long enough and the number of times they can be charged and discharged — in other words, their life — is limited.
Blocks of batteries can currently provide power some four or five hours.
“What happens when you have a wildfire, and your power supply is off for two days?” Knox asked.
NRG’s partner in the project is San Diego Gas & Electric. Spokeswoman Stephanie Donovan agreed with Knox that the utility would not have been able to obtain 500 megawatts of carbon-free electricity.
The new plant will be a vast improvement for San Diego’s grid over the existing Encina plant, Knox said. Local power lines already have 35 percent renewable energy coursing across them. Encina cannot respond swiftly to changes in real-time renewable energy from sun and wind. The Encina boilers have to be heated for 12 to 18 hours in advance to keep all their metal from expanding unevenly.
“You want this plant operating tomorrow, you have to tell them to begin operating today.”
All that time, the boilers are consuming gas and polluting, Knox said.
It is clear why NRG wants to build the Carlsbad power plant. It already owns the large industrial property on Agua Hedionda Lagoon, where it will be built. High-pressure gas pipelines already deliver there. And NRG must either invest heavily or close the existing Encina steam plant to comply with the Clean Water Act. That type of plant, which sucks in millions of gallons of seawater to cool steam and discharges it back into the sea warmer, is no longer acceptable. The new one will be air cooled.
It is equally clear why San Diego Gas & Electric wants the plant: It will pipe gas to the new plant and then buy the electricity made from burning it. It adds the $2.2 billion cost into electricity rates, including a guaranteed profit for 20 years.
(That cost cannot be verified with the Public Utilities Commission because the agency does not release price information for three years after a power plant goes online.)
Off most of the time
Most peaker plants in Southern California are turned on an average of only 6 percent of the time.
They “can be expensive assets that are not used very often,” Lin said.
Mike Shurtleff, a naval electronics and computer engineer who closely follows battery developments, suggested that if a plant is used very little, then that opens up another alternative.
“If that’s all they’re doing, then they might just want to invest in incentives for home batteries,” he said. When people install batteries at their homes, as some already do, the homes draw less energy from the electrical wires, from the grid.
But NRG estimates the new 558-megawatt peaker plant in Carlsbad will run three times as much as the old one at the site does — about 15 percent of the time. (It is permitted to run as much as 31 percent.)
How much the new plant in Carlsbad runs, of course, dictates its emissions.
And how you assess those emissions depends on where you sit. NRG, SDG&E and proponents prefer to compare the plant to Encina.
It is projected to be much cleaner than the 63-year-old plant.
Also, compared to the list of other peaker plants in the San Diego region, Carlsbad is projected to be the cleanest for greenhouse gases — half a metric ton per megawatt hour.
But other people think the correct comparison is with the San Onofre Nuclear Generating Station — a source of carbon-free energy until suddenly, it was not. Vespa said Carlsbad should be compared with modern zero-emissions alternatives.
“At the end of the day, it is burning fossil fuels to run. Extracting gas from the earth is very polluting, burning it is polluting it, and there isn’t anything clean about it.”
The new Carlsbad plant also adds one contaminant to the air that has received little attention — ammonia. Ammonia is injected into the smokestacks to neutralize a different pollutant, nitrogen oxides. The ammonia is a smog-limiting device.
If the new plant runs just 6 percent of the time, it will release an estimated 17,446 pounds of ammonia per year, according to state documents. That would make it by far the largest industrial emitter of ammonia in the county, according to records from the Air Pollution Control District. The next largest emitter, the Point Loma wastewater treatment facility, gives off less than half that much.
Why care about ammonia? Ammonia can turn into particles. Particle pollution is linked to a long list of health problems including stroke, respiratory issues and low birthweight babies.
San Diego air officials said in documents in the Carlsbad proceeding they believe the local air is not likely to convert the ammonia into hazardous particles. But Kimberly Prather, a particle expert at UCSD, said the compound is not well studied; the only small particle-making molecule that is not regulated.
“There are no controls on ammonia,” she said. “I think it is amazing that it hasn’t been regulated yet.”
Some other places in the world, Panama and Tanzania for example, are only now getting their first natural gas power plants. In those places, natural gas is the new clean energy, replacing dirtier coal, diesel or oil burners. U.S. coal plants in the Midwest and East are getting replaced with natural gas at a pace few would have predicted just a few years ago. In California, it is a different story. The era of new fossil fuel plants here may be closing.