This content is brought to you by the Propane Education & Research Council.
Last month, the Environmental Protection Agency announced awards for round three of its clean school bus rebates. As with previous rounds, most of the funding went to electric school buses. To date, the EPA program has allocated more than $2.8 billion for 8,427 electric school buses and 440 low-emissions propane buses.
While the five-year program justifiably aims to replace the nation’s aging, dirty diesel buses, electric models should not be the default replacement of choice. Research shows that more affordable options can lead to lowering emissions faster.
School buses travel more than 3 billion miles each year, providing transportation to more than 25 million American children every day. The rebates, therefore, have the potential to make a huge impact on air quality and decarbonization by replacing existing school buses powered by diesel. EPA’s Clean School Bus Program allows applicants to request battery-electric, propane or compressed natural gas buses.
Eliminating diesel-powered buses is a vital goal. Diesel fuel has a high carbon intensity, and when burned, emits ground-level air pollution that is unhealthy to breathe. Electric vehicles address some of the problem, but don’t actually solve the climate change issues we face today.
Unfortunately, the U.S. electric grid is not as clean as most people think. While renewable energy is being added at a considerable pace, fossil fuels are still being used to meet peak energy demand. The average carbon intensity of the U.S. electric grid is roughly 137 grams of CO2 equivalent per megajoule (gCO2eq/MJ). In comparison, conventional propane has a carbon intensity of 79 gCO2eq/MJ, and renewable propane made from the cover crop camelina has a carbon intensity of only 20 gCO2eq/MJ.
Leaving conventional diesel behind is a good move, and it can happen today with a combination of clean energy resources.
Rebate applicants and the EPA should also consider cost in their deliberations. At $375,000 each, electric buses with charging infrastructure cost about three times more than a propane-powered bus. The cost-prohibitive nature of electric models means school districts may only be able to convert a small portion of their fleets, especially in disadvantaged communities where budgets are often constrained. By choosing propane-powered buses, districts can replace three times the number of diesels to lower CO2, NOx, SOx and particulate matter.
School districts nationwide are realizing that converting traditional fleets to EV is no simple solution. The environmental benefits are less clear, and the grid is simply not ready to service the load. As journalist H.L. Menken once said, “For every complex problem, there’s a solution that is simple, neat, and wrong.”
According to the U.S. Energy Information Administration, about 60% of U.S. electricity still comes from fossil fuels. The cleanliness of the grid varies by state, so it’s important to understand how electricity is being produced regionally.
While major investments are being made in renewable energy, the transition is not happening at a fast enough pace to keep up with load growth. Transmission infrastructure delays and permitting requirements are two major challenges that must be overcome to accelerate grid decarbonization. Grid operators have announced concerns about being able to reliably serve demand due to the intermittent nature of renewables and the retirement of older, dirtier power plants.
Eliminating things like diesel fuel because clean, affordable alternatives are available is a responsible step. This is the wide path ahead — using a variety of ever-cleaner technologies to match the daunting energy-intensive challenge. We applaud EPA’s Clean School Bus Program and hope to see the agency’s awards embrace a holistic view.
Visit propane.com to learn why propane school buses are the smart choice for today’s student transportation needs.
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