Backup Power

Function and Importance

Escalating frequency and severity of extreme weather events may increase interest in backup power systems. For example, the catastrophic Oregon wildfires of 2020 and their corresponding widespread power outages showed how changes in the climate may increase the need for backup power. Wildfire risk to grid infrastructure may result in utilities implementing proactive Public Safety Power Shutoffs, or other protective measures to ensure public safety. In California, these shutoffs have increased demand for backup power — the 2021 California study found that total capacity of backup generators increased by 34 percent from December 2018 to 2021.

Solar panels and storage at the Wheatridge Renewable Energy Facility. Photo: OPB

Electric Vehicles and Backup Power

Ford F-150 Lightning Pro

Electric vehicles are an emerging potential source of residential backup power. In 2022, Ford released the F-150 Lighting, an electric pickup truck that provides automatic backup power in the event of a power outage. The base model includes a 98 kWh battery pack, and the extended range model a 131 kWh battery.18 Ford estimates that the extended range option could provide up to 10 days of backup power to a residence, and touts this benefit in one of its TV commercials. Ford has partnered with the solar company SunRun to provide integrated solar charging systems for the Lightning and is developing a home integration system.

Fossil Fuel Generators and Solar Plus Storage

The Oregon Department of Energy office in Salem has a 300-gallon diesel backup generator that can provide power to critical agency equipment for about 24 hours in the event of an outage or emergency.

Most of the backup power systems serving commercial and industrial loads are diesel-fueled generators. There are no recent studies analyzing backup generators in Oregon, but a 2021 study conducted in California found that nearly 90 percent of existing commercial and industrial backup generators are fueled with diesel, 6 percent from natural gas, and the remainder from other fuels, such as propane. Permits for new backup generators also indicate a strong preference for diesel-fueled systems. In Crook County, Oregon, the Apple and Facebook data centers together hold permits to operate 222 diesel generators totaling more than 600 MW of capacity.

Battery storage paired with onsite renewable energy systems is an emerging backup power technology in Oregon. These systems typically use rooftop solar to charge wall-mounted battery storage packs. Solar plus storage systems can be continuously recharged without the need to store or procure fuel during a natural disaster but must be sized appropriately and rely on variable solar resources for recharging. In Oregon, battery storage systems are becoming more commonly used in residential applications; on a larger scale, solar plus storage systems may be used to power microgrids, providing power to critical infrastructure and making Oregon communities more resilient. However, there are limitations to the amount of power that can be generated and stored with onsite solar-plus-battery storage systems.

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