Can We Transition to a Zero-Emissions Future in Public Transportation?

The transportation sector is the biggest emitter of greenhouse gas, releasing one-quarter of all GHG emissions. It’s a high-impact target for reductions — but what are the best strategies to cut transit emissions, while still connecting people with their destinations?

If you’ve ever breathed in a lungful of traffic exhaust on a hot summer’s day, you know intuitively that it’s pretty noxious stuff. But what your lungs can’t tell you is just how much road traffic contributes to harmful emissions that impact climate change.

The transportation sector is the largest contributor to greenhouse gas (GHG) emissions in the U.S., wheezing out 29 per cent of total GHG produced. In Canada, transportation sector estimates measure in at about 24 per cent of GHG emissions.

Diesel engines are a significant source of emissions — as it stands, they’re a serious offender when it comes to air pollution. In larger cities where diesel-engine buses are heavily used, buses alone can account for 0.78 pounds of CO emissions per passenger mile. With annual ridership in the hundreds of millions, you’d better believe those emissions add up fast.


Cutting emissions

It’s clear that the transportation sector is a high-impact target for reducing our GHG production. So what are the best strategies to start cutting down on transit emissions? Transitioning to electric buses is one move to help reduce emissions dramatically — and it’s a high-impact change with a broad range of benefits. Electric buses have a significant impact on reducing tailpipe emissions, but we also need to be aware of upstream emissions generated from the electricity.

For instance, adding 729 next-generation, clean-diesel and 254 hybrid-electric vehicles to the Toronto Transit Commission (TTC) fleet over four years is projected to save 64,200 tons of GHG-causing emissions every year.

Although electric vehicles aren’t causing a massive drop in barrels of oils, as reported by Bloomberg, electric buses are. For every two electric buses on the road, one barrel of oil is removed from circulation.

There are other environmental benefits as well. Let’s not forget the urban noise reduction of an electric bus, from both inside and outside the vehicle. Electric buses create a significantly lower level of noise, which can improve noise pollution in urban centers.



What about the costs of replacing entire bus fleets with newer, more tech-forward models? Far from being a sunk cost, investing in electric buses can actually generate serious savings.

In a report for Halifax Transit, WSP estimated that an electric bus fleet could save between $127 million and $163 million over the next 20 years.

Electric buses can create a significant reduction in maintenance costs per kilometre due to the lack of an internal combustion engine and other components. Engine and transmission overhauls are no longer needed, and WSP has found savings in preventative maintenance activities such as oil changes and extended life for brakes. Fuel cost is another major component for a transit agency, and our research shows that electric buses can reduce this line item greatly. Over the life of the asset this can translate to thousands of dollars in savings for operations and maintenance. On the other hand, battery and traction motor overhauls (depending on the annual kilometres driven) need to be factored in.

Electric BusElectric Bus

Fuel cost is a major component of hourly service cost for a transit agency as well. Our research shows that electric buses can reduce this line item greatly.


Leading the charge

If electric buses are a low-risk, high-reward inevitability, how to we begin the implementation process? Like any other large-scale change, it is a gradual transition process requiring detailed planning and strategic deployment. Tools like WSP’s proprietary BOLT route simulation model or lifecycle database can provide invaluable data to plan an electric bus fleet that serves a city’s needs while streamlining operating costs and slashing GHG emissions.

A WSP project in Lima, Peru provides an excellent example, because WSP was brought in from day one when the project was being conceived we worked with the local transit agency to map the routes, which would be optimum for a pilot program. We worked with the municipality and NGO to develop a specification, which would meet all local requirements and maximize battery range. Moreover, this project operational plan was developed by WSP as a pilot to accelerate adoption of electric buses in Peru with all the data being monitored in real time for performance and KPIs.

Shifting gears toward more sustainable power sources in the transportation sector is a groundswell that’s gaining momentum fast. And when clearing the air from harmful GHG emissions comes with long-term operational cost savings, the benefits are too good to ignore. For municipalities considering making the change, the only question left is when.


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