ELECTRIC TROLLEY: LINK Transit in rural Wenatchee, Wash., uses five, Ebus-built, seven-meter long, 22-passenger trolleys with 28 kWh-batteries that travel on two separate eight-kilometer-long loops and can be filled in about seven minutes with a fast charge at the downtown Wenatchee Transit Center.
Image: Courtesy of Nick Chambers
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Better lithium ion batteries have led to an explosion in availability of plug-in passenger cars. And now, thanks to relatively cheap electricity and the simplicity of the electric drivetrain, electric vehicles have even more potential for use in the extremely cost-sensitive public transportation arena—a concept that is only just taking root.
In particular, two projects funded mostly by grants from the American Recovery and Reinvestment Act of 2009 (ARRA)—better known as the stimulus package—are pioneering new ways that public transit systems both large and small can think about total cost to operate buses and their environmental impact in the burgeoning era of cheaper, large format, lithium ion batteries.
Different needs, same goal
Spanning from Pasadena to Pomona in an area east of Los Angeles, Foothill Transit is a large bus operator serving about 14 million passengers per year over a 900-square-kilometer area. On the other end of the spectrum is LINK Transit, based in rural Wenatchee, Wash., which conveys just one million passengers annually—but unlike the compact footprint of Foothill Transit, its lower passenger volume is spread out over an area about 10 times larger.
Both public transit operators place significantly different demands on their buses, but each has trained its long-term vision on battery power as a way to reduce costs, improve operational efficiencies and reduce environmental impact. During multiple-year electric bus projects that were funded in 2009 but didn't pick up steam until 2010 (and in the case of LINK, still aren't fully in place), the operators are using different equipment and battery technology to see if their projections pan out in the real world. The projects were mostly funded by ARRA grants, with LINK receiving $2.9 million (of which all went to purchasing electric buses and associated charging equipment) and Foothill receiving $21.3 million (of which only a portion went to the buses and associated equipment).
Lithium ion batteries are still not energy dense enough hold more than the equivalent of between four and eight liters of gasoline in a battery package small enough to put on a bus. Nevertheless, inherent efficiencies in the electric drivetrain enable significant increases in fuel economy. Whereas a typical 12-meter-long, diesel-powered transit bus might return between one and two kilometers per liter, the electric ones that Foothill is running average the equivalent of 8.5 kpl. After some quick math it is apparent that 8.5 kpl combined with 7.5 liters of energy storage is not enough to fuel the hundreds of kilometers a bus might need to travel in a day. To get around this, both Foothill and LINK have added ultrafast charging stations in the middles of their buses' loops.
Foothill Transit operates three 12-meter long, 35-passenger buses built by Greenville, S.C.–based Proterra. Each relies on batteries that supply 72 kilowatt-hours and runs on a 27-kilometer-long loop that handles 5 percent of the yearly ridership. At specially built fast charging stations in the Pomona Transit Center the buses can fill up within 10 minutes on their normally scheduled layover, meaning they never have to travel more than 27 kilometers between full charges—about half what their rated battery capacity can provide. LINK's system is similar, although it uses five, Ebus-built, seven-meter long, 22-passenger trolleys with 28 kWh-batteries that travel on two separate eight-kilometer-long loops and can be filled in about seven minutes with a fast charge at the downtown Wenatchee Transit Center.
LINK originally planned to have its electric trolleys up and running by late 2010, but issues with the battery cooling system and manufacturing of the fast-charging station delayed full operation until later this year—although the trolleys are currently running for about two hours each day without fast charging. "There's nothing off-the-shelf about our trolleys," says Greg Pezoldt, special projects coordinator at LINK Transit. "As the first electric trolley of its kind, everything we have done with Ebus we've had to develop and sometimes redevelop. Even with the delays we're still excited about it, and we have an ultimate goal of electrifying the entirety of our Wenatchee and East Wenatchee routes."
Cost savings achieved
It is no wonder LINK is still bullish on the endeavor: Pezoldt says a comparable diesel-powered trolley would cost about $435,000 and each electric trolley built by Downey, Calif.–based Ebus costs significantly less at $370,000. On top of that, diesel fuel for the same trolley on the same route runs about $1,200 per month, whereas the inexpensive and green hydropowered electricity used for the Ebus trolley comes in at approximately $100 per month—less than one tenth the cost. The biggest question revolves around battery life, but even with the worst-case estimates, Pezoldt says LINK still comes out significantly ahead with electric bus operation in terms of lifetime fuel and maintenance costs.
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17 Comments
Add CommentLuckily the electricity to charge the batteries is produced with zero emissions? (while also forgetting the environmental load of the production, installation, maintenance, and ultimate disposal of the vehicle itself)
Reply | Report Abuse | Link to thisA trolly on rubber wheels...who would've guessed? That is a nice looking trolly though. With those savings in favor of E-buses and the improvements coming fast with batteries, transit systems would be a fool not to transfer over.
Reply | Report Abuse | Link to thisThey didn't say 'zero emissions', they only said there are 'zero tailpipe emissions'. This is pretty beneficial for urban air quality.
Reply | Report Abuse | Link to thisWhy would the production etc of these vehicles be any more energy intensive etc than with a diesel bus? Frankly I don't know the lifecycle impact of one vs the other, but I see no specific reason to think there's a huge difference.
Overall it sounds like this is a fruitful line of development. The thing is we've optimized the heck out of ICE systems. While there's always SOME more to be gained it is telling that these electric buses are ALREADY at a similar level of utility, price, efficiency, etc and they are far further down on the optimization curve. It is hard to imagine that the electric bus of 20 years from now won't be vastly superior, at least for the kind of applications being discussed here. I'd imagine they will have wider applicability as well.
Believe it or not, when I posted my comment, the article was completely different than the one that appears now. It led off with a statement about a 'zero emissions' solution. I agree with the points in this new content.
Reply | Report Abuse | Link to thisI wonder if the local fish, especially the spawning salmon, would agree to the term "green hydropowered electricity"?
Reply | Report Abuse | Link to thisElectric buses are great, but they are nothing new. In fact, most electric vehicles sold are for commercial & industrial applications
Reply | Report Abuse | Link to thisIn an October 24, 2011 article, Electric Vehicles Research indicated that currently 60% of the value of the electric vehicle market is being spent on commercial and industrial vehicles – and this trend is expected to continue and grow into the next decade.
Heavy industrial vehicles (those used do heavy lifting, such as forklifts) make up the largest segment of the market. This is understandable, since by law, forklifts must be electric to be used indoors. While little opportunity may remain in this market, there are plenty of other uses for electric vehicles in the commercial and industrial sector.
Airports are under increasing pressure to switch their Ground Support Equipment (GSE) to pure electric versions, both on and off the tarmac. Besides lowering their carbon footprint, this would lower their cost of ownership, cost of maintenance and their exposure to price increases in fossil fuel supplies.
Governments, wanting to be perceived as environmentally conscientious, will help to drive the continuing growth of the commercial and industrial EV market.
This market is seen as being less dependent on government incentives and funding than the more fragile personal EV market, and innovations seem to appear in the industrial and commercial market sooner.
Electric vehicles offer so many advantages over traditional vehicles in the industrial/commercial environment. Electric delivery vehicles cope better with frequent stopping and starting. Electric shuttles can be used to transport visitors through industrial plants, airports, and other venues with no concern about noxious emissions. Rangers can use electric vehicles to access areas of parks and natural areas where it is important that environmental impact be limited. The applications are only limited by the imagination!
I was a little disappointed that there wasn't more information about the truly unique characteristics of both of these systems. They both use AltairNano Lithium Titanate batteries plus ultra-fast charging to achieve all day running without huge battery packs. These buses charge at about 240kW for a few minutes at the end of the route. This is enough juice to get to the other end of the route and charge again.
Reply | Report Abuse | Link to thisThese LTO batteries can be charged extremely fast, and also have a super long number of times they can be charged. Perfect for buses that run the same route and can be charged every hour or so. They aren't so good for cars because they weigh more than the other types of lithium batteries. Since you only charge your car maybe once a day, car batteries need to have very high energy per kg. Buses are different since they run the same route all day and can charge at the route ends.
Trolley buses?!? Trolley buses are buses that run on overhead power lines, and Streetcars are trolley buses that run on rails. Unbelievable, but Greenies are still pushing the dumb idea of streetcars & trolley buses. The rails are a death trap for cyclists, and the overhead trolley lines are very expensive, unreliable and make moving large loads through a city very difficult. A really obsolete idea. The only sensible use of trolley lines nowadays is for LRTs or Electric Trams with multiple cars for high volume corridors, and even those could soon be converted to batteries and/or ultra-capacitors, with inductive charging.
Reply | Report Abuse | Link to thisBoth the Proterra & Ebus are poor examples of what EV tech is capable of. Believe it or not the drivetrain of the Tesla Model S sedan is more powerful with larger batteries than the Proterra Bus. With an 85 kwh battery, a 270 kw motor, 45 min recharge, 1 min battery swap, it is quite capable of running a City Bus, with about a 85 km range between charges. It also would not be difficult to convert existing smoke belching diesel buses to battery electric, that would be the most cost effective way to rapidly replace diesel buses with Electric, with much lower operating and maintenance costs.
And full lifecycle analysis of EVs vs ICE vehicles indicate similar embodied energy & emissions in both, and both are only about 15% of the full lifecycle emissions of the vehicles, most of that comes from fuel consumption, or grid mix Electricity emissions. Even fed from a Coal power plant, a typical EV is equivalent in full lifecycle emissions to an ICE vehicle getting 45 mpg.
Too bad California is ripping off its citizens with high Electricity prices due to its whacky Renewable Standards Portfolio idiocy. The biggest source of Green Energy in California is its Nuclear Power plants. They would be much better off abandoning their devious, cowardly, secretive Renewable Energy massive subsidies, and start on a Nuclear Power build, then their Electric City buses would be even cheaper to operate.
Great progress being made, I would say :)
Reply | Report Abuse | Link to thisTrolley buses run in Seattle on several routes and seem to do very well. Also, how much can the battery pack be sold for when it declines to say 75% of original capacity. I understand that old battery packs may be more useful recycled intact to users who don't need the full capacity.
Reply | Report Abuse | Link to thisTrolley buses are archaic, and need to be replaced with battery electric buses. Usually Battery Packs for EVs will be replaced when they have about 80% of rated capacity. They are quite valuable at that time for off-grid storage batteries, and utility storage batteries, and there is a big demand for them, utilities are already negotiating with EV manufacturers for buying expired battery packs.
Reply | Report Abuse | Link to thisIt would seem that adding a resonance-charging system at one or more stopping points along the route would be an improvement over any "trolly" connection or even manual plug-in wherever for a recharge. The primary coil would likely be underground with the secondary permanently mounted under the bus on the framework. Trolly-supplied power is so yesterday, to use our children's expression.
Reply | Report Abuse | Link to thisWhy not use a trolly connection where it exists as a recharging device for a bus battery? Who cares if it is not the latest technology?
Reply | Report Abuse | Link to thisThe horseless carriage (automobile) got its start because it used a type of fuel also used by some kitchen stoves. The fuel was available anywhere in the United States and most of the rest of the world. Blacksmiths could repair them and existed in every town in the country. Thus the automobile was a conservative change and did not require a brand new infrastructure. It could exist alongside the horse and buggy and eventually provide the replacement.
A new technology should start off trying to use an existing infrastructure or simply use one at the home base. We could create filling stations that would provide a hybrid with both gasoline and a battery charge. When enough filling stations had battering charging capability, then we could go over to electric cars. Such would use current technology.
Instead of using the phrase "federal grant money" be honest and say "taxpayer funded"
Reply | Report Abuse | Link to thisInstead of using the phrase "federal grant money" be honest and say "taxpayer funded"
Reply | Report Abuse | Link to thisRetpro1...true, and whats your point...
Reply | Report Abuse | Link to thislamorpa...don't know why your not more concerned with the lack of water exiting streams than the damning of them...just check out the colorado...
Reply | Report Abuse | Link to this