The dark side of California’s emergency grid rescue plan: More dirty emissions from backup generators

Late last month, California Gov. Gavin Newsom did what little he could to shore up the state’s stressed-out power grid in the midst of a second year of summer heat waves, drought and wildfires. To address a potential grid supply shortfall of up to 3.5 gigawatts, Newsom’s emergency proclamation waives air pollution restrictions on natural gas plants and diesel backup generators when they’re used during grid emergencies. The emergency waivers also offer similarly relaxed emissions regulations on large ships, allowing them to fire up their diesel engines instead of using on-shore electric power while docked at California ports.

Two weeks later, the first anniversary of the August 2020 rolling blackouts came and went with little fanfare. Although wildfires continued to rage across California, driving people from their homes and putting even more smoke into the air, the state was spared a repeat of the intense heat wave that gripped the U.S. West.

But environmental advocates worry that Newsom’s desperate attempt to avert grid imbalances by relaxing emissions rules will exacerbate unhealthy air, particularly in disadvantaged communities, and worsen the climate change patterns that are fueling bigger and more frequent wildfires.

“By using dirty power to keep the lights on, we are just adding to the climate debt that our kids and grandkids will pay,” Dan Jacobson, senior director of Environment California, wrote in an email last month.

Fast-tracked fossil expansion

In another action called for by Newsom’s emergency order, the California Energy Commission recently agreed to speed up permit approvals for new and expanded natural-gas plants and diesel generation to get more power online by the end of October. This new maximum 10-day permit approval process waives air and water protections for expansions of gas plants and the building of new fossil generation of 10 megawatts or larger.

To accelerate the deployment of new resources, the Energy Commission executive director is authorized to approve the fossil plant permits, and that decision cannot be appealed. The new gas and diesel generation is allowed to stay online for five years, although the plant owners are to install pollution controls within no set time frame, or ​“as soon as practical,” according to the order.

Air-quality regulators and clean-air advocates are concerned about the health impacts of higher emissions in the fifth-largest economy in the world, particularly those from diesel engines. The particulate matter and nitrogen oxides in diesel exhaust can cause and exacerbate respiratory illnesses and heart disease, including asthma in children, and increase cancer risks.

The South Coast Air Quality Management District, which regulates air quality in the often-smoggy Los Angeles basin, has expressed concern that increased operations of power plants and emergency diesel engines will disproportionately affect disadvantaged communities, according to an email from spokesperson Bradley Whitaker following Newsom’s order. That includes the many struggling communities around the large ports in Long Beach and Los Angeles.

“The potential for excess emissions of oxides of nitrogen and diesel particulate matter from emergency engines operating over their permitted limits is significant,” Whitaker wrote.

The Bay Area Air Quality Management District is also ​“concerned about diesel combustion throughout the Bay Area and the associated public health impacts on impacted communities,” spokesperson Kristina Chu said in an early August email.

Newsom’s directive acknowledges this ​“vicious cycle in which generating energy contributes to the very climate-impacted emergencies that threaten energy supply.” The governor, who also issued similar directives earlier in July and last year, faces a recall election next month. The state’s last such recall in 2003 saw former Gov. Gray Davis, who was blamed for the state’s 2001 energy crisis and energy deregulation debacle, ousted by Arnold Schwarzenegger.

Zeroing in on the impacts of diesel generation

The use of diesel generators has already soared in California over the past three years, driven by widespread grid outages imposed deliberately by utilities to forestall the threat of power lines sparking deadly wildfires. Beyond generators at homes and small businesses, large diesel projects have been exempted from California Energy Commission permitting, and hundreds of megawatts of utility diesel generators have been approved by the California Public Utilities Commission.

Diesel generators are cheap, powerful and usually widely available. But their increasing use harms human and climate health, more so because the newer ones will likely continue to be in use for decades, California Air Resources Board attorney Wesley Dyer told the state’s Energy Commission last November.

In Southern California, the South Coast Air Quality Management District has about 11,000 active permitted emergency engines in its jurisdiction. There also are other portable emergency engines that may be operating in the area that are registered through the California Air Resources Board, according to district spokesperson Whitaker.

The district analyzed the potential for NOx emissions under a fire-prevention grid shutoff in which 523 emergency engines in the affected area run for 24 hours.

“The resulting potential daily NOx emissions, over 36 tons per day, were much greater than the average daily NOx emissions from the eight refineries in South Coast AQMD’s jurisdiction,” Whitaker said.

In the Bay Area, there are about 9,000 emergency engines, most diesel-fueled, with an unspecified number using less-polluting biodiesel, according to the Bay Area air district’s spokesperson Ralph Borrmann. A number of generators were installed before emission limits were set. Outside of emergencies, the backup systems run about 14 hours a year for maintenance and testing.

Diesel backup use continues to grow

Jakub Zielkiewicz, a climate adviser with the Bay Area district, told the Energy Commission during a January 2021 forum on alternatives to diesel backup that the number of backup systems in the region over the last three years has grown by about 3,000 units. Of those, 60 facilities have a combined 1 gigawatt of diesel generation. Another 1.5 gigawatts of diesel backup capacity is being installed at data centers.

The average amount of time these generators run has also shot up. Last year, for example, one company ran its diesel backup 400 hours above its permitted allowance, Zielkiewicz said. Newsom’s emergency order officially allows these generators to run for two hours before to one hour after a grid emergency is declared without regard to pollution limits.

The California Energy Commission certifies large diesel projects between 50 and 100 MW but has largely exempted them from the state permitting process, putting them under the local air districts’ jurisdiction. Air districts set emission limits for systems larger than 50 horsepower, but the restrictions do not apply during emergencies, notably during power outages.

The governor’s order requires operators of power plants and diesel engines to report within 48 hours the time and amount of excess emissions to the local air district, the California Air Resources Board and the state’s Energy Commission. They are also to report the type and quantity of fuel used, additional hours the units ran and additional energy produced within 30 days of the event.

Similar emissions reporting was required under Newsom’s previous emergency orders. When asked via email to provide information on increased emissions during grid emergencies, California Air Resources Board spokesperson Dave Clegern replied, ​“We don’t really have any data that falls into this category.”

Mitigation plans and long-term threats

The California Air Resources Board must also develop a mitigation plan for air pollution increases by this November.

“We will be watching carefully to see if mitigation is done in a meaningful way,” said Bill Magavern, policy director for the Coalition for Clean Air, a statewide organization that advocates for clean air policies.

Whitaker, the South Coast air district spokesperson, said that mitigation should include ​“investments in programs to improve air quality in communities, with a particular focus on disadvantaged communities, and to reduce risk to sensitive populations.”

Chu, the spokesperson for the Bay Area air district, said that agency has been collaborating with other state energy agencies and municipalities ​“to transition backup diesel generators to cleaner alternatives — such as battery, mechanical and fuel cell power systems.” The air district has been talking with the state’s Air Resources Board and Energy Commission about changes ​“that may be necessary in the state regulatory scheme to lessen or eliminate the use of diesel backup engines,” she added.

Magavern also highlighted the need for ​“greening the peak with storage and demand response so we don’t get stuck again in this situation. The communities most at risk from air pollution and climate change are forced to bear the burden of the poor planning of the past.”

Tapping customer resources to alleviate grid stress

Newsom’s emergency order will increase payments to large commercial and industrial energy users that reduce energy use during grid emergencies — also known as demand response — but allows them to use backup generators to fill the gaps. Since last August’s rolling blackouts, the California Public Utilities Commission has taken some steps to expand the value of demand response programs.

Companies involved in that business have complained that the CPUC’s actions haven’t been aggressive enough to expand participation from customers equipped with smart thermostats or home batteries. Meanwhile, California’s efforts to add gigawatts’ worth of utility-scale batteries to help relieve the grid have struggled to keep pace with climate-change-induced stresses, including a drought that’s dried out reservoirs and sapped about 1,000 megawatts of hydropower resources from the state’s available capacity.

These impacts in California mirror worsening conditions across the U.S. West and across the globe. More backup generators and gas generation may help prevent grid emergencies in the short term but end up worsening the conditions that are causing the emergencies if they’re not replaced with cleaner alternatives, and sooner rather than later.

(Lead image: Pxhere.com)