Hydrogen bus pilot attracts international attention

The hydrogen bus pilot by the City of Edmonton and Strathcona County caught the attention of planners across Canada and the United States during a June 9 presentation. Virtual attendees from British Columbia, Nova Scotia, California, Texas, and beyond tuned in to learn how research conducted by the city and the University of Alberta shows promise for diversified fuel sources for municipal vehicles. Hydrogen-powered buses outperform electric vehicles in cold weather, researchers found, leading them to posit that there's cause to deploy different kinds of buses depending on the time of year.

Bahram Bahri and Mahdi Shahbakti from the U of A's Energy Mechatronics Lab gave performance metrics for the hydrogen-fuelled Route 9 in Edmonton and Route 441 in Strathcona County in comparison to diesel- and electric-powered buses. The researchers found that EVs are the most energy-efficient option during warm service hours, but suffer the most when it's cold. Hydrogen buses have greater resilience at below-zero temperatures, while diesel vehicles are largely unaffected by climate conditions. Therefore, the pair and the city's Patrick Baltazart suggested the region could cut its emissions more effectively in the winter with hydrogen than with EVs. That said, hydrogen production is on a colour scale with varying degrees of carbon emissions. The City of Edmonton has worked with Calgary's Azolla Hydrogen to fuel its buses. Brent Lakeman, the executive director of the Edmonton Region Hydrogen HUB, earlier told Taproot that Azolla's methanol-to-hydrogen method differs from producers who truck in hydrogen from as far away as Texas and Arizona. Azolla's biodrome technology does not fit neatly into the colour scale, but purportedly has 21% fewer greenhouse gas emissions than grey hydrogen.

Where is just as important a question as when, speakers noted. Route 441 in Strathcona County outperformed Edmonton's Route 9, offering further considerations for deploying hydrogen-fuelled buses. Speakers said higher traffic density and a greater concentration of stops on a route hinder the performance of H2 buses. Route 441 has just 0.8 stops per kilometre compared to 3.2 stops per kilometre for Route 9, and it idles less, allowing the Strathcona County route to make more efficient use of the alternative fuel.