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To Really Cut Emissions, We Need Electric Buses, Not Just Electric Cars
An anonymous reader writes: All the EV attention these days is going to Tesla and other sedan manufacturers, but this article makes the case that it's far more important to switch our buses over to electric power than our cars. "Last year, according to the American Public Transportation Association, buses hauled 5.36 billion passengers. While usage has fallen in recent years, thanks in part to the growth of light rail and subway systems, buses still account for more rides each year than heavy rail, light rail, and commuter rail combined—and for about half of all public transit trips." This, while managing around 4-5 miles per gallon of gas, and public buses usually average about 50,000 miles per year. The electric buses themselves are significantly more expensive, but the difference is made up dramatically lower fuel costs. And there will be difficulties: "The range—up to 30 miles—limits Proterra buses to certain routes, so it's hard for an agency to go all in. Drivers have to be trained to brake and accelerate differently, and to maneuver into the docking stations. And Doran Barnes of Foothill Transit notes that some of the cost advantage of using electricity instead of diesel can dissipate. Electric cars can be charged at night, when power prices are low. But buses have no choice but to recharge in the middle of the day, when utilities often impose higher peak usage rates."
San Francisco has had a fairly extensive trolleybus network since the 1930s. Although only 15 bus lines are trolleybuses, those are the most crowded bus lines, so a significant fraction of bus traffic there is electrified.
It appears that diesel buses cost $450,000, and battery-electric buses cost $825,000, and trolleybuses cost $1m each. Trolleybuses last at least twice as long as diesel buses. The overhead wires cost $2 million per mile and last almost indefinitely, it appears, because I have never seen maintenance being performed on any of them, in contrast to roads and stoplights which are being repaired constantly, and buses which are being replaced often enough.
San Francisco has 300 trolleybuses for 15 lines, and each line is about 6 miles long. Thus the overhead wires cost $180m, the buses cost $300m, and the electricity costs $48m over 24 years. It appears that equivalent diesel buses would cost $270m and use $330m in fuel over 24 years, servicing the same routes (just using the numbers I read from an article and doing the calculation manually). It would appear that trolleybuses cost ~$528m for those routes and diesel buses would cost ~$600m. However, that's not taking into account financing costs etc, which would probably make the trolleybuses more expensive than diesel ones since the upfront cost is higher. Also, this is for routes in San Francisco which are only 6 miles long; the economics may change for suburban routes.
That said, it doesn't seem like the costs are very different whether we choose trolleybuses, diesel buses, or battery-electric buses. It may be slightly more expensive to go electric, but not much.