When discussing electric vehicles with skeptics, I often hear a familiar refrain: “Electric vehicles aren’t really clean, because the energy used to power them is created by fossil fuels.” A valid point, although perhaps overstated given that the grid is rapidly embracing clean technology and electric vehicles still release far fewer emissions than gas or diesel-powered models even when using fossil fuel-powered electricity.
Likewise, clean energy skeptics are quick to say: “We can’t transition to solar and wind energy because it’s not reliable enough and our electrical grids don’t have the storage.” Indeed, outdated infrastructure and a lack of energy storage are important challenges to resolve.
There is no overnight fix for these issues. But clean energy and transportation are interdependent: Making progress on one front will help accelerate change on the other.
We know that increasing the share of clean energy used to generate electricity will help reduce the emissions connected to electric vehicles. Similarly, electric vehicles – in particular, electric school buses – could provide critical storage for power grids switching to renewable energy.
By transitioning to electric school buses, the United States could ensure clean air for kids (electric buses don’t release dirty diesel fumes that threaten children’s health), reduce climate-harming emissions from transportation, and strengthen renewable energy infrastructure – all at the same time.
Vehicle-to-grid technology and electric school buses
How would electric buses support renewable energy? Electric school buses have large batteries that can store significant amounts of power. When equipped with something known as vehicle-to-grid (V2G) technology, these buses can return this stored energy to the electrical grid. In this way, electric buses can absorb renewable energy when it is available in abundance and release it during periods when it isn’t, such as at night (in the case of solar). This flexibility helps reduce the grid’s overall fossil fuel use, reducing carbon emissions and making clean energy more reliable.
These gains are significant. A new U.S. PIRG Education Fund report estimates that replacing every yellow school bus currently in operation across the United States with a V2G-capable electric bus of the same type would create a total of 61.5 GWh of extra stored energy capacity – enough to power more than 200,000 average American homes for a week.
One 2016 study found that the use of V2G in electric school buses could eliminate an average of more than 1,000 metric tons of CO2-equivalent greenhouse gas emissions over the lifetime of the bus – equivalent to the emissions produced by more than 200 gas-powered cars per year. Indeed, the use of V2G would completely offset air pollution from the fossil fuels used to create the power for electric buses.
Electric buses could even eliminate the incentive to invest in new coal and gas projects. A California study found that switching to V2G-capable electric vehicles would help make solar energy more reliable – potentially avoiding the construction of 35 new natural gas plants.
V2G technology’s potential is profound, and electric school buses offer a perfect starting place. Unlike personal vehicles, school buses are typically owned and operated together in large fleets by school districts or school transportation companies. That simplifies the installation of charging infrastructure and makes coordinating with electric grid operators easier.
Furthermore, school buses are generally only in operation twice a day, five days per week, during the school year. That means school buses sit idle the vast majority of the day at predictable times, maximizing the time they can use V2G to store and return energy.
Supporting a renewable future
It’s already worth transitioning to zero-emission electric school buses just to protect children’s lungs from harmful diesel pollution. When the climate and grid benefits are considered as well, the case is even stronger.
Replacing all of the country’s diesel powered school buses with electric models would in itself contribute to a sizable reduction in greenhouse gas emissions, avoiding roughly 8 million metric tons of emissions per year. That’s a big step towards cleaning up America’s transportation sector, which is the number one contributor to climate change in the United States. And switching to electric is far more effective than turning to false solutions like propane or natural gas buses, which could have higher greenhouse gas emissions than electric, still emit harmful tailpipe pollution and offer no pathway to a truly zero-emission future.
But electric buses still have even more to offer – when equipped with V2G technology, they can support the transition to renewable energy, helping to clean up two parts of America’s infrastructure at once.
The sooner we can roll out electric school buses, the bigger the benefits. School districts should invest in large fleets as soon as possible, and coordinate with electric utilities from an early stage. Regulators and utilities should invest in V2G pilot programs and develop creative financing programs to start taking advantage of V2G grid benefits. State and federal governments should support the transition by continuing to invest in electric school buses and supporting research on standardizing V2G technology and business models.
Electric school buses can drive a cleaner future for transportation and energy. It’s time to get rolling on a clean ride for kids and a cleaner electric grid for all.
Director, Environment Campaigns, PIRG
Matt oversees PIRG's toxics, transportation and zero waste campaigns and leads PIRG’s climate program to promote a cleaner, healthier future for all Americans. Matt lives in Amherst, Massachusetts, with his wife, two daughters and chihuahua.