Cleaning up power production on Catalina

The current power production system at Pebbly Beach Generating Station will need to be replaced in the next two years in order to reduce emissions and meet new more stringent regional air quality standards. Photos By Elisa Ferrari and Ron Hite

By Jude Schneider

For the Islander

Since 1962, Southern California Edison has been providing electric service to Santa Catalina Island’s 4,100 residents, businesses and roughly 1 million annual visitors. Catalina is located 22 miles offshore and is not connected to the mainland’s electrical grid. The island’s electrical power has mainly been generated by aging diesel-fueled locomotive engines, working alongside a fleet of propane-fueled micro-turbines and a long-serving battery energy storage system.

This current system, parts of which have been in service since the 1950s, will need to be replaced in the next two years in order to reduce emissions and meet new more stringent regional air quality standards.

“The goal for this new system is to continue to provide reliable and safe electric service to the island, while reducing air pollution emissions by at least two-thirds,” said Jim Buerkle, SCE director, Generation. “Our long-term goal is to increase the use of renewable energy, energy efficiency and demand response on Catalina, in keeping with SCE’s commitment to a clean energy future.”

In 2018, the South Coast Air Quality Management District implemented a new regulation that limits the amount of nitrogen oxide that can be released on the island. Nitrogen oxide is a pollutant that contributes to the formation of smog. Five of the current six generators do not meet this air quality requirement and cannot be upgraded.

To evaluate the leading repower options, SCE commissioned a study, “Santa Catalina Island Repower Feasibility Study,” from consulting group NV5 in partnership with the Federal National Renewable Energy Laboratory and U.S. Environmental Protection Agency. The study analyzes the cost, schedule, benefits and challenges of several new approaches to powering the island.

“The current diesel generators are nearing the end of their lifespan, so we look at this regulation as a timely opportunity to examine alternatives to power the island while improving air quality and increasing the use of cost-effective renewable energy, energy-efficiency and demand response measures,” added Buerkle.

While the study does not provide a recommendation, it suggests that the only feasible approach to timely meeting the air emissions regulations is to replace five of the existing generators with new, much cleaner, emissions-compliant diesel generators.

The study determined that a large share of solar energy, such as 60% or 100%, would be very expensive to implement now. Other forms of renewable energy, such as wind and wave power were also examined, but would not be practical or cost-effective for Catalina today.

The study also revisited the idea of connecting Catalina Island’s power supply with the mainland via an undersea cable — an idea which was last studied in 2004-2005. This option would cost almost twice as much as emissions-compliant diesel generation or a diesel/renewable mix over the next 30 years and could entail significant permitting delays as well as risk given the depths the cable must travel. That option would also require diesel as backup generation for the island if an issue occurs with the cable, which could require a lengthy repair timeline.

“The study does suggest that adding some solar energy and additional battery storage can decrease the project’s cost over 30 years by decreasing the use of diesel fuel,” said Buerkle. “And, as renewable and energy storage technologies improve and their costs come down, additional amounts of both may become economical.”

The next steps in repowering Catalina will be for SCE to begin the public permitting process before the South Coast Air Quality Management District. That filing is expected this year. SCE will also be reaching out to Catalina Island stakeholders and providing opportunities for residents to learn more about the study.

“At a minimum, we are going to reduce nitrogen oxide emissions by almost two-thirds — and this is just in the near-term,” said Ron Hite, SCE senior manager of the island’s utilities, who has been responsible for water, gas and power on Catalina for 17 years. “This is great news for the residents of Catalina.”

Costs of the selected project will be shared across SCE’s 5 million customers, subject to review and approval by the California Public Utilities Commission as part of the utility’s General Rate Case.

More information on the project is available at