As climate change and resulting extreme weather events wreak environmental and economic havoc on the globe, power outages have become increasingly problematic.

In California, for example, public safety power shutoffs have been implemented as a stopgap measure for mitigating increasingly intense wildfires. And the U.S. as a whole isn’t faring much better: The average American went eight hours without power in 2020, more than twice as long as 2013, according to the U.S. Energy Information Administration.

To deal with these outages, building and design professionals have turned to power generators as a partial solution. But, with all the options available, which fuel source is ideal? Power Generation: The Emissions Shifting Problem, a new report from the Propane Education & Research Council, sheds light on this question with evidence that shows propane can provide emissions and resilience benefits, particularly compared with diesel.

“Replacing diesel assets with propane-powered equipment will continue to push us toward significant air quality improvement and decarbonization,” says Gokul Vishwanathan, author of the report and director of research and sustainability at PERC.

As architects and engineers evaluate power generation solutions that can provide resilience in the face of outages—and help in the battle against climate change—this report provides clear data to help inform their decisions. Here are some of the highlights.

1. Propane can displace diesel generators in many markets and significantly improve air quality, mainly by lowering the release of nitrogen oxides (NOx) and particulate matter into the air. The use of backup generators has surged in recent years. In California, for example, the number of backup generators increased 34% from 2018 to 2021 in the Bay Area Quality Management District and 22% from 2020 to 2021 in the South Coast Air Quality Management District, according to M.Cubed, an economic and public policy consulting group based in Oakland, California. Currently, 90% of the backup generators in both the districts are powered by diesel.

But this prevalence of diesel generators doesn’t mean they’re the best choice for architects and engineers worried about air quality. Propane engines can improve air quality by providing significant particulate matter and NOx emissions reductions relative to diesel, according to the PERC report. Depending on whether the engine is optimized for propane, propane generators can also provide CO2 emissions reductions. (See the report for the full comparison data.)

2. Renewable propane can help with decarbonization. There’s more than one type of propane available to put in that propane generator. Renewable propane—produced from renewable feedstocks such as used cooking oil and animal tallow using hydrotreated vegetable oil process—is identical to conventional propane structurally and functionally. But it can lead to a between 50 and 70% reduction in lifecycle CO2 emissions compared with conventional diesel and can accelerate deep decarbonization. And to add to the fuel’s flexibility, blends of conventional and renewable propane are also practical solutions for accelerating the crucial process of decarbonization.

For a deeper dive into these insights and more, download the full report: Power Generation: The Emissions Shifting Problem or learn more at