Seattle’s trackless trolley electric backbone (RouteFifty)

When transportation planners drool over the Emerald City’s transit successes, they shouldn’t overlook the decades of investments in this legacy asset.

In transportation circles, the word “trolley” can sometimes come with decades-old reputational baggage. Getting around on one might seem antique and quaint, best suited for tourists taking in local attractions at a leisurely pace, not daily commuters trying to get from Point A to Point B.

But that’s not the case in the Pacific Northwest’s largest city where there’s a nearly 80-year-old system of “trackless trolleys” in addition to more familiar transit modes like buses, streetcars and light rail. Instead of steel-wheeled vehicles guided by tracks set in the pavement and powered by a single overhead wire, the trolley network in Seattle uses rubber-tired buses and two poles that follow a set of overhead wires that deliver power to the vehicle.

Unlike streetcars that can’t leave their tracks, trolleybuses can travel around obstructions in the roadway—say, an Uber driver stopped to let out a passenger or an idling delivery truck—thanks to the flexible poles that are set on springs that allow such movement. In hilly cities like Seattle, electric trolleybuses are better at ascending long, steeper grades compared to diesel buses.

And because they’re electric, trolleybuses are cleaner and far quieter compared to diesel vehicles. The ride is far smoother, too, with braking technology that allows trolleybuses to return power to the overhead wires. Newer trolleybuses also have the ability to travel offwire for shorter distances on battery power.

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4 comments

  1. I’ve long thought that Britain’s severe reluctance to even consider trolleybuses as a serious option for the development of various transport corridors a great shame.

    At a time when reducing particulate emissions in cities is ever more important and when renewable energy is increasingly prevalent (in the case of solar – whose peak supply is more or less at the same time as peak transport demand – during the day) – that the historically extensive trolleybus networks around the country have been destroyed with little to no hope of reinstatement is a travesty. Maybe there were good reason for it at the time, but hindsight – at least in my eyes – has not been kind to that decision.

    Yes electric buses might be able to replace them to some extent – but the benefits of integrating this new battery technology into new generation trolleybuses far outweighs the benefits of electric buses alone (no need for extra diesel engine for example, fewer energy losses due to battery charging, since overhead wire transmission losses are smaller, no problems with weight limiting passenger capacity and damaging roads more).

    Yes that comes at the cost of some physical infrastructure – but even that has its benefits (wayfinding – if a road has trolleybus wires above it, there’s a good chance that a trolleybus runs along that road somewhere!). Historical issues with off-wire running, complex junctions, and overtaking have long since been solved – in many cases using the above-mentioned battery technology.

    I get the feeling that there’s a lot of re-inventing the wheel going on, with new, untested technologies being hyped instead of the mature, proven to be effective technology that does the same thing more effectively – Borismaster with a pantograph anyone?

  2. London once had the world’s largetst Trolleybus sytem.
    And we threw it away & replaced it with “Routemasters”
    Some of us, at the time, thought it was a mistake, but no-one listened.

  3. I live in Seattle, smack between two of our trolleybus routes, in the Central Area, east of downtown. The climbing abilities of the trolleys make the diesels look silly (particularly when we have diesel substitutes for some reason). The trolleys are quiet, they don’t pollute the air, and the newer buses also do a much better job at staying on the wire. They really are one of the best parts of the hodge-podge that is Seattle transit these days.

  4. @JohnSea

    As a former resident of Vancouver BC, I similarly loved the quiet, hill climbing trolleybuses. But Seattle is finally expanding LRT and streetcar lines. I had posted some Seattle links in March and April 2018 Friday Reads posts, such as.

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