Climate change is our national emergency. Zero-emission buses (ZEBs) are a critical technology in the fight against climate change as well as public health threats -- and cities around the U.S. and across the world are already reaping the rewards. But there is still a lot that needs to be done to dispel myths around electric buses, prioritize investment, and address our massive transportation pollution problem.
Transportation is now the largest source of emissions of all energy sectors in the nation, responsible for more than 28 percent of greenhouse gas emissions. The overwhelming majority of areas designated to be in nonattainment with federal air quality standards are congested urban areas that rely on dirty, polluting buses for public transit. Smog from buses and other vehicles drives up asthma rates across the country, with children under 18 and low-income communities bearing the greatest burden. As cities attract more people, and thus more cars and air pollution, there is no room for fossil fuel buses in a future where climate justice is a priority.
In addition to providing invaluable public health and environmental benefits, ZEBs are cheaper to maintain and cost less than diesel and compressed natural gas alternatives over a vehicle’s lifetime. Bloomberg New Energy Finance estimates the global number of electric buses in operation in 2017 at roughly 385,000. At the beginning of 2018, only 300 battery electric buses were on US streets. The two leading manufacturers in the US market – BYD and Proterra – report total sales of almost 1,300 buses through 2018, an overall 30 percent increase in ZEB deliveries. Additionally, commitments from California and major transit hubs, including New York City and Seattle, to go 100 percent electric with their bus fleets have led to estimates that electric buses will make up one-third of the national fleet by 2045. We need to move faster.
One thing is for certain: ZEBs are on the rise in the US. However, this transformational technology faces hurdles like higher upfront costs, range anxiety, concerns about cold weather performance, and myths spread by fossil fuel interests whose profits are threatened by the future of electric transit. Rather than disqualifying the technology, these challenges indicate a need for more focus and investment in the growth of the electric bus sector.
Estimates indicate that electric buses will reach subsidy-free, purchase-price parity with diesel buses by the mid 2020s, 2030 at the latest. Factors like increasing fuel prices, greater efficiency in manufacturing, and declining battery costs will all drive down the upfront cost of ZEBs. Today, although ZEBs cost $200,000 more than diesel alternatives on average, they save an estimated $400,000 in fuel and maintenance costs over the course of their lifetimes.
As more and more electric buses are produced, the cost per unit falls. The standard Proterra bus was valued at $1.2 million in 2014. Today, it costs around $700,000. With plenty of remaining undetermined funds from the VW Settlement and programs like the federal Low or No-Emission Bus Program, there is no indication that subsidies for public transit and school buses will be phased out anytime soon. In addition to plentiful grant resources, financing options (including battery leasing, joint procurement, and bus sharing) are bringing costs down for transit agencies across the country. This report by Environment America provides some excellent electric bus financing examples.
For agencies across the country that are already facing declining transit ridership, reliability of service is a priority. This has produced concerns about range -- the distance an electric vehicle can travel on a single charge -- of electric buses and their ability to service popular routes. Concerns have been intensified by recent reports from Albuquerque, where a fleet of electric buses was returned after not meeting promised range metrics. While this represents a real challenge to the development of the ZEB industry, it hardly disqualifies electric buses as a viable option for many routes.
The average transit bus in the U.S. travels 130 miles a day. New Flyer Xcelsior CHARGE buses currently provide an operating range up to 275 miles, a figure that will continue to increase as battery technology advances. In 2017, Proterra broke the world record for miles traveled on a single charge of any electric vehicle when one of their buses traveled 1,100 miles.
Battery and charging technology is constantly improving with new fast-charging stations being piloted in countries from Chile to New Zealand. Companies like Proterra, New Flyer, and others are catalyzing this innovation in the US and seeking to make 24/7 electric bus service a near-term reality. Wireless-charging technology also seeks to expand the range and service potential of ZEBs without requiring midday layovers.
When extreme heat and cold set in, battery efficiency tends to decrease. Battery charging and regenerative charging through braking are also limited in cold weather. EV car owners get around this issue by being aware of this and making sure that they maintain above 20 percent capacity in their batteries to ensure the vehicle has enough reserve to power up.
Reports of electric buses not performing well in the cold don’t always paint the full picture. For example, a Proterra pilot bus in Minneapolis in a no-cost trial was recently reported as requiring “ongoing charging” throughout the day due to poor cold-weather performance, making it appear as if the bus could only travel one loop (16 miles) before running out of charge. Proterra’s staff clarified that because the bus was running loops all day, the operators capitalized on short intervals of charging in the time between loops to keep the battery full in preparation for a longer route (over 100 miles) that was planned for later that night. This was a unique trial situation; on normal routes in extreme cold weather, the same bus is capable of running over 120 miles on a single charge.
Electric bus manufacturers are offering an expanding array of options with different specifications and capabilities. As options increase, the range of routes that electric buses will be able to service also increases. Cities facing extreme cold weather should invest in buses with higher battery capacity and more-efficient drivetrains to cope with the seasonal shifts. Manufacturers are also developing auxiliary heating systems that reduce the draw on the battery in cold weather. As the innovation accelerates toward new technologies, including solid state batteries, sophisticated cooling, and charge monitoring, electric buses will be able to outperform conventional models in almost any climate.
Some have raised concerns about the range and efficiency of electric buses in cities with large elevation shifts. Transit officials in Los Angeles also reported issues with diminished range and stalling on hills for their BYD buses. That being said, other transit officials in California where electric bus adoption is surging argue that stalling, breakdowns, and other technical issues faced by diesel and propane buses do not face the same level of scrutiny and press coverage as electric bus challenges. Proterra’s DuoPower drivetrain seeks to address this issue by doubling horsepower and acceleration on buses with this feature. You can see the results for yourself; these buses can handle hills of up to 26 percent grade, double the performance metrics of standard diesel buses.
The Road to Electrification
According to this recent report, 13 percent of all U.S. transit agencies have electric transit buses in their fleets -- or have ordered them. Asking whether electric buses are “ready” for the road is a waste of time. They are here offering real-world benefits, the number of transit agencies committing to them is increasing, and the technology is improving. Any new technology experiences iterations of troubleshooting that spur innovation. Even cities that have experienced challenges with the technology, such as Los Angeles, have doubled down on their commitments to full fleet electrification by 2030. New York City’s MTA has committed to all electric buses by 2040. California recently committed to all-electric transit buses statewide by 2040. The environmental and cost benefits associated with electric buses will only continue to grow. Early adopters will be the first to experience these benefits, and transit agencies that delayed and doubted the potential of this technology will be left having to explain to their customers what took them so long to hop on board.