Pacific Gas and Electric Company is considering building a 300-megawatt power plant in Lodi that could store energy in the form of compressed air and release it during peak use hours. It would be the third of its kind in the world, if the current study finds Lodi a feasible location.
A representative from PG&E confirmed the company is in discussions with the city of Lodi about the potential lease of city property to build the plant. A tentative timeline sets the activation date sometime in 2020.
“This is a very long-term project, but we believe it will help assist us in providing reliable energy services to our customers,” said Nicole Liebelt, PG&E spokeswoman.
The Lodi City Council was introduced to the project during Wednesday’s closed-session meeting. City Attorney Janice Magdich said the power company approached Lodi some weeks ago about leasing 20 acres near the White Slough Pollution Control Center south of the city.
Lodi has all three factors the power company is looking for in potential project sites, said Liebolt. That includes a location above the flood zone, existing electric transmission lines and natural gas pipelines, and porous bedrock under the soil.
The power storage process is a little like saving leftovers from lunch for a later dinner.
During off-peak hours, renewable energy is created through solar panels or wind turbines and run to a motor. That motor uses the energy to compress air and shoot it underground into depleted natural gas reservoirs. It remains in the reservoir until the energy demand spikes. Then, pressure turbines pull the compressed air out of the ground, where it powers a generator to produce electricity.
“When the sun is shining and wind is blowing, that’s great, but at night when folks get home from work, that’s when you need (more energy),” said Liebelt.
If the project is successful, Lodi could be the site of only the third compressed air energy storage plant in the world by 2020. One exists in Germany and was built in 1978, while another was built in McIntosh, Ala. in 1991.
The proposed project is part of a study by PG&E using a $25 million grant from the U.S. Department of Energy. That grant was matched by the California Public Utilities Commission, with another $1 million pitched in by the California Energy Commission. The idea is to study the viability of porous rock as a storage medium for compressed air. If approved, the Lodi project would be the main demonstration of that study.
Liebelt made it clear there is no rush.
“There’s a lot of steps in the process and we’re following it carefully,” said Liebelt. “We want to give those interested in the project the time to provide us with input.”
At the Wednesday council meeting, Councilman Bob Johnson said the city needs to create a plan about what projects are appropriate for the 1,000 acres of city-owned land at White Slough.
“We need to take a moment to see what we really want to put out at White Slough and create a priority list in our best interest, not the best interest of the people who are coming to us,” he said.
The California Air Resources Board has required the state to provide 33 percent of its energy using renewable energy sources like solar and wind power by 2020. But the challenge is finding ways to store that energy during times of low usage. The state believes compressed air may be a solution; hence the PG&E study.
“It would be groundbreaking to see this kind of technology in California,” said Liebelt. “Renewable energy storage is one of the most environmentally and economically sound forms of bringing more energy onto the grid.”
Contact reporter Sara Jane Pohlman at email@example.com.