Last week I got a chance to check out one of Metro’s new Proterra’s electric battery-operated buses. It was parked at Microsoft for an hour and I was lucky enough to talk with a rep from Proterra and the bus driver. Previous coverage of the new buses can be found here.
The bus was 40 feet long. It has a charger on the top of the bus for use with the rapid charging system currently installed at EastGate. It also has a side charger port that you could theoretically also use to plug in the bus via a cord.
One thing that stuck out was that the bus body was made out of composite materials and not sheet metal. This significantly reduces the weight which helps increase the range of the bus. The interior of the bus has 40 seats and can accommodate 37 more standing passengers for a total capacity of 77 passengers. 28 seats are forward facing while the remaining 12 face inwards towards the center aisle. All interior lights are LED which also help efficiency.
The back of the bus houses the motor, inverter and the transmission. I was surprised to hear it has a 2 speed transmission, but apparently this was necessary to reduce the current needed to start the bus from a stop and for slow speeds. With less parts than a conventional diesel bus, it allows for a rear window, which most Metro buses don’t currently have. The top speed is rated at 65 miles per hour. 8 battery packs line the floor of the bus between the rear and front wheels.
The documentation I got from the Proterra rep states that the bus typically gets 1.7 kWh per mile with full passenger load and full HVAC. They claim a nominal range of 60 miles, which would but the battery capacity at 102 kwH.
I didn’t receive any information on the total cost of the new bus, but I’m sure it’s significantly more expensive than a diesel or hybrid diesel coach. But the maintenance and fuel energy costs will be much less. Over a 12 year lifetime, the company estimates that energy costs will be $81k while maintenance costs will be $300k. That’s much less than the cost of a Diesel or Hybrid bus which run between $700k – $800k for that same period. So that equals out to around a $300k savings over a conventional bus over its lifetime.
Metro is currently doing testing with large water jugs on each passenger seat to simulate a load of passengers and measuring how well the bus performs. The bus driver didn’t know when they would enter service, but they gave a hint that they were hoping they’d be ready by sometime in the spring and the likely first route would be from EastGate to Seattle.
I’m really hoping the tests go well and that Metro will not only confirm the large cost savings compared to conventional buses, but will be much better for the environment with how much hydro power our area produces.
Great report! Thanks. Should note hydro power has a cost too in terms of habitat loss, fish kills, etc. Hopefully more solar and wind generation will arrive soon.
Let’s just remember what the alternative’s are. This is a phenomenally clean and efficient source of energy using already built power sources. In 21st Century America, that is the best it gets right now.
Still, good old trolley buses are the best in terms of power efficiency. If we can just combine this and trolley infrastructure for our entire 15 minute all day frequent network, we would have the cleanest transit system in the country.
I really need to be brought up to enough facts for a workable comparison between buses running on battery rather than line power.
One question I have, both for buses and hybrid streetcars, is how well they handle a crush load on a very steep hill in heavy traffic.
Performance also needs to include powering such ventilation and air-conditioning, since unventilated confinement on a vehicle whose window don’t open-is both bad PR and probably a crime.
But where trolley wire is still necessary, one thing batteries might do is greatly simplify “special work”- the extra complicated hardware needed to let wires cross each other without serious damage to all equipment.
Should be possible to make the whole crossing “dead”, and let the battery push the bus to where the live wire begins again. Which brings us to the main point in all vehicle procurement:
Don’t start discussion with what the vendor has for sale- but on what we need out of it. Above paragraphs, good example.
Mark
Hopefully, battery powered buses can one day provide all the benefits of trolley buses, but without the trolley wires. This would open up some interesting routing possibilities. For example, the 13 could extend northward over the Fremont bridge and eastward to the U-district, replacing route 32. Besides finally providing a decent connection between upper Queen Anne and areas to the north, it would also eliminate duplication between the 32 and the D-line along Interbay, freeing up service hours to run the extended 13 more frequently.
Just eliminating the overhead from neighborhoods would be a huge plus for anyone tired of looking out their front windows seeing nothing but wires. Eliminating a permanent line-crew on stand-by saves buckets of money. An finally, keeping the fleet rolling because some operators spend lots of time putting poles back would be a big hit with the riders.
With the new trolley order coming on-line, they have 15 years to figure this out.
Totally agree! I’d also add that the maintenance costs of battery-electric vs. overhead wires is so much less. Maintaining overhead wires is expensive. Metro typically runs diesel buses on the trolley routes on weekends since there’s so much work to do maintaining the overhead wires. And because the wires are all connected, it’s really hard to work on one section of wire and still run a trolley on the entire route.
Long-term, maintenance costs are significantly lower for trolley wire than for battery-electrics, because the batteries *do* wear out eventually, and they’re expensive to replace. The wire lasts an extremely long time.
But this is without considering “special work” on the trolley wires, which is super-expensive to maintain. I think the future of trolleybuses is to have no specialwork at junctions. Carry enough batteries to drop the wires before the intersection and pick up them up again after the intersection.
I used to live in front of the wires in and a layover and I loved it. The hum of an electric bus is soothing compared to the idle of diesel. The trolley bus sound as it rounded the corner was beautiful and the wires might not be beautiful but they look cool and it isn’t like living under an elevated train. On the weekend in the winter when the trolleys were replaced with regular buses when drivers would lay over and idle, the diesel fumes and the sound was horrible.
You guys are maligning something that is truly wonderful about Seattle. It would be better if the wires could be invisible, of course, but I would take trolley buses on my street any day over any car. Batteries are the perfect interim solution where we don;t have trolley wire but not the ultimate answer as they rely on the world’s very limited supply of lithium and waste a ton of energy.
Drew, THANK YOU! I used to live at Sixth West and Galer before the old tight overhead was replaced. One of the magical things about the old system was that it “sang” as the bus approached: “tsingggg-tsinggg” softly. Since my stop was around the curve from Sixth to Galer it was nice to be able to hear the bus coming and know that it was almost there.
I like Nathanael’s idea of powering through route divisions on batteries and eliminating the special work. There needs to be a pretty fail-safe method of re-wiring the poles in order to do that, though. Didn’t the dual-mode tunnel buses have something like that at IDS and CPS?
You can have the experimental battery bus that wears out, I’ll take the tried and true local icon trolley buses with clear routes marked out in the sky.
This solution would be a great mitigation for the proposed BRT on the ERC through Kirkland where people question whether a multi-use trail should co-exist with BRT.
Electric buses would certainly help, at least with the noise aspect. But, it wouldn’t be a panacea. When a car or bus is traveling above 30 mph, the bulk of the noise comes from the air striking the car and the tires rubbing against the road, not the engine. Where the impact of electric buses on noise would be most noticeable would be slow routes like the 48 trying to climb up Capitol Hill.
It also wouldn’t do anything to address the huge impact of the construction of the busway itself, nor would it address the fact that a busway would effectively cut of one side of the trail from being able to access it.
I agree that battery-electric buses are going to replace nearly all diesel buses for city-bus service in the very near future. There are three brands in active use in the US:
Proterra (which you reported on)
BYD (used in some LA-area municipalities and being ordered by WA)
New Flyer (being used in Winnipeg and Chicago)
All three of them seem pretty nice. They also have very similar specs — but the Proterras have by *far* the shortest range before recharging, with New Flyer advertising a 120 mile range, and BYD advertising a 155 mile range.
Eastgate to Seattle seems like a waste of the strong suit of an all electric which is heavy stop and go service. I understand they are tied to the Eastgate charging station but surely there’s better test routes that can be come up with.
Well, if the electric test fleet is all 40-footers, that immediately excludes the more popular routes. I suspect also that Metro is intentionally phasing in the electric buses on less popular routes first so, if they run into unexpected issues, fewer people would be impacted. It also helps, of course, that Eastgate Transit Center had sufficient space to install the charging station.
It’s the runs rather than the routes that matter. You’re only going to be running the battery electrics on trippers unless you want to drastically increase the amount of deadheading.
http://www.facebook.com/groups/moreelectricbuses