Posts Tagged ‘GLT’

Adiós Seattle’s Trolley Buses?

May 10, 2010

It seems transit authorities are taking a hard look at Seattle’s trolley bus system, with an eye to abandon the service. The problem in Seattle, as in Vancouver, the trolley buses are only seen as a electric bus, not a different transit mode suited for a specific job. Trolley buses should be used on heavily used routes, especially hilly routes, with stops every 450 metres or more. Broadway is a prime example of their ill use as if a European style trolley bus service were to be used, there would not be any need for the diesel 99B-Line express buses.

The term ‘hybrid‘ tends to scare me as it is the term used with experimental operation and that translates into expensive operation.

In the real world, trolley buses are slowly becoming a thing of the past, being replaced by low-end streetcars or more glitzy proprietary GLT or guided bus.

Fate of trolleybuses hangs in balance

King County Metro Transit’s fleet of 159 trolleybuses need to be replaced soon, but what they should be replaced with is up for debate

By Mike Lindblom

Seattle Times transportation reporter

About one-fifth of all King County Metro Transit rides are made on an electric bus, powered by a nonpolluting trolley wire overhead.

But the agency hasn’t purchased a new trolleybus since 1979.

Since then, Metro bought new bus bodies and fastened old electric motors onto them. They pulled out the diesel engines from a fleet of dual-mode buses, so they ran only on their electric motors. These minor miracles saved the public tens of millions of dollars.

Now the day of reckoning has arrived.

By 2014, the agency expects its fleet of 159 trolleybuses to wear out.

At the Sodo maintenance base, trolleybus-maintenance manager Mike Eeds pointed to a crack in a steel roof member, near the rear door of a bus. It’s not a safety hazard but could cause leaks — and cracks are expected to spread through the fleet. Worn-out teeth were being replaced on the same bus’s drive axle. Metro has been cannibalizing spare parts, but those will run out by 2016, he said.

County elected officials must decide by next year whether to retire the old trolleybuses, buy new-generation models or switch to some other technology.

An audit last year suggested tearing out the overhead wires and switching to hybrid buses, whose diesel engines are supplemented with onboard batteries. Doing so could ostensibly save $8 million a year compared to trolleybuses, by reducing electrical-maintenance costs and making route schedules more flexible, the audit says.

But many residents along the routes, and Seattle transportation director Peter Hahn, insist on preserving electric buses because they are quiet and nonpolluting. Seattle ranks third of only six cities in the U.S. and Canada that operate trolleybuses, behind San Francisco and Vancouver, B.C. Edmonton removed its trolleybus wires last year, but Laval, Quebec, is considering a brand-new system using local hydropower.

More than pollution

The debate here involves issues far beyond pollution and noise, with a major consideration being torque — electric motors have superior power to turn bus axles coming off a dead stop.

“San Francisco and Seattle have hills that are alike, up and down. There’s no way you can put diesel buses on the hills,” says Nathanael Chappelle, Metro’s 2007 co-operator of the year. Eeds agrees, saying a “straight hybrid” wouldn’t work.

Midway up Queen Anne Hill, a former cable-car route, the Number 3 and Number 13 buses stop for passengers on a 15 percent slope. When the wheels turn again, the acceleration pushes people firmly into their seat backs. The best drivers wait for all to find a seat, or feather the accelerator pedal, so as not to topple unstable riders in the aisle.

Larry Nelson, living in a fourth-floor hillside apartment, says sparks fly off the wire or the tires spin on damp pavement. Still, that’s better than smelling diesel, he says.

In the overhead network, there are dead spots where electricity is interrupted, so a bus must build momentum to coast through, but not faster than 10 mph.

Take a curve too fast, and the power poles fall off the charged wires — trolleybus driver Chai Kunjara compares the physics to a waterskiier who swings wide faster than the powerboat.

Despite the quirks, he says, the steering handles smoothly, the dashboard console is simple and one can navigate by following the wires, though sometimes drivers forget and stray off them.

The downside of trolleybuses is inflexibility. In the ice storm of December 2008, several trolleybuses on First Hill became stuck, paralyzing the central-city service as the following buses couldn’t pass. Diesel buses can go around stalls — Metro says it will “dieselize” its electric Number 70 route for three years because of the upcoming Mercer Street reconstruction.

Trolleybuses cost $1 million or more, compared with $720,000 for diesel-hybrids. Auditors also point out there’s only one North American trolleybus maker, exacerbating the risk of higher costs.

On the other hand, Vancouver is happy with its 2007 models by Winnipeg-based New Flyer, and expects them to last more than 20 years each. Dayton, Ohio, imported Czech buses for final assembly in the U.S. Hahn argues there’s no danger a robust international trolleybus industry will go extinct.

Exploring options

The County Council has ordered a technical study. Councilman Larry Phillips, D-Magnolia, argues electric buses support the fight against sprawl, by making busy city neighborhoods more pleasant.

The timing is awkward. Hydrogen vehicles or plug-in electric buses seem promising, but Metro can’t wait until those technologies mature. That leaves other options:

• Order a trolleybus with supplementary batteries charged through overhead power and regenerative braking — so the bus can sometimes detour off-wire.

• Combine overhead power with a supplementary diesel motor, for long or short stretches off-wire.

• Travel wire-free using electric batteries and high-torque motors, to be recharged by a diesel motor running at a steady, fuel-efficient rate. Metro General Manager Kevin Desmond also hopes to research whether there’s a bus available to use overhead power in-city, then continue off-wire several miles farther out.

Just last year, Metro published a paper describing a better “Rapid Trolley Network” that provided trips as frequent as every six minutes. There could be off-board payment and roomier vehicles, like a train. New wires over Denny Way, Yesler Way and East Madison Street would fill gaps in trolleybus routes.

When the county took over Seattle bus lines in 1973, the deal guaranteed “electric trolley service” shall continue, transportation Director Hahn’s letter emphasizes. The city is writing a new transit plan that likely would keep or even expand the lines, he said in an interview.

“We believe, in terms of climate change, greenhouse-gas goals, this is the most reliable technology.”


Let’s ride on the Clermont-Ferrand TransLohr GLT -Courtesy of U-Tube

October 27, 2009

This is an interesting U-Tube of the TransLohr GLT or guided bus. The centre rail is for guidance only as the tram like bus is propelled by standard rubber tires.

Tram on Tires – Guided Light Transit (GLT), the ultimate BRT

October 26, 2009


Guided Light Transit or GLT is a hybrid bus/tram system, where rubber tired vehicles are guided by a single rail and the TransLohr GLT falls into this category. It has been long realized that for a bus to obtain higher performances to compete against LRT, it must be guided. The Achilles heel of BRT in busways is that the kinetic envelope needed for BRT operation is much greater than LRT, thus the land take for a busway was much more expensive than for light rail. The Ottawa busway cost more to build than for originally planned for LRT! To reduce the kinetic envelope for buses, they must be guided and the German O-Bahn addresses this problem by side wheels running on a cement guide-way. Visually ugly, the guide-ways have not proven popular and are almost impossible to locate in city centres, which means the O-Bahn operates just as a bus in the city. In Germany, this problem has been some what overcome by O-Bahn track-sharing with LRT on reserved rights-of-ways and in tunnel; though problems still persist.

By guiding a bus by a single rail (monorail?), flush with the street (like a tram), enables the GLT to safely operate in city centres, within its kinetic envelope thus providing the bus with most of the benefits associated with light rail- but at a cost as GLT became only a little cheaper than LRT, but with a much more limited capacity than light-rail and limited productivity as GLT buses can’t operate in multiple unit. In Paris, GLT is more expensive to build than tram!

The new Paris tram-on-tire or GLT line Saint Denis-Sarcelles (6.6 km) will serve some popular destinations, as well trying to revitalize strategical urban areas. Many modal interchange points will be located along the route: Marche de Saint-Denis (T1 tramway line), Saint-Denis Basilique (metro Line 13), Garges-Sarcelles (RER local railways Line D), besides many other bus interchange stops.

A further standard tram line (steel wheels) will also serve Seine-Saint-Denis department, connecting Saint-Denis, Epinay-sur-Seine, Villetaneuse and serving Universitè de Paris XIII-Villetaneuse. It will interchange with metro L13 (Saint-Denis Porte de Paris stop) and tram T1 (Gare de Saint-Denis stop), but not directly with Saint Denis-Sarcelles line.
RATP (official site)

What is interesting to see is the cost of  Paris’s new GLT, CAD $52.7 million/km is much higher than Le Man’s new LRT line costing $31.2 million/km. or Paris’s tramway T-3 cost of $42.5 million/km! It seems the TransLohr GLT or tram on tires is very expensive for what it does and like SkyTrain, be built in very numbers.

It is important to note, when provincial politicians espouse the notion of Bus Rapid Transit as an alternative to LRT, Rail for the Valley must expose this nonsense as both BRT and GLT could be more expensive to install than light rail and certainly GLT/BRT will cost more to operate than LRT.

Country France
Line Saint Denis-Sarcelles
Inhabitants District 11.175.000
Date opening 2011
Future development:
Length (km) 6.6
Track sections
Stops 16, average distance 400 m
Platform doors
General characteristics
n. of vehicles 15
n. of cars per vehicle 3
Type rubber tyres bi-directional
Vehicle dimensions (m) length 30, width 2.2
Vehicle capacity (pax) 127
Frequency 5’/
Type of guide/gauge central rail
Speed Km/h Comm. 18, Max —
Accel./Decel. (m/sec2)
System capacity
Ridership 30.000 pax/day
Total cost 33 M Euro/km
System builder LOHR
Model Translohr STE3

Mobilien: Paris Version of Bus Rapid Transit. But could LRT do a better job?

October 25, 2009

The following  U-Tube presentation of Paris’s Mobilien BRT is interesting and shows what buses can do in congested cities, such as Paris. The observation can be made:  “that for a few dollars or Euros more, would not the modern tram bring more benefits to both the city and transit customers on these routes?” The articulated diesel buses used by Paris’s Mobilien, pollutes the air and spews diesel particulate a proven carcinogen, while LRT, run by electricity, is very environmental friendly. If electric buses were to have been used, then the cost difference between BRT and LRT would greatly decrease.  The higher commercial speeds for Mobilien are achieved by using dedicated rights-of-ways and preemptive signaling, which by strange coincidence is more basic that a trams, yet there is no howls of protest that BRT will cause accidents at every street corner as we constantly hear from the anti-LRT crowed.

In France, exhaustive studies done between bus and tram and a few interesting points have been made. To be competitive with a tram BRT must be guided, like the O-Bahn or the various proprietary GLT systems. Unguided BRT has a poor record in attracting new ridership has transit customers just think it is a bus and is the main reason that GLT vehicles (buses) look like trams! LRT lines cost about 30% more to build than GLT, but with the higher price for light-rail, one gets higher productivity, higher capacities, and higher commercial speeds and is for those reasons, many towns have opted (most by public vote) to build with light rail.

One interesting aspect of France’s LRT program is that one third of the cost of tramway is set aside for landscaping, etc. but with BRT the subsidies must be used for road layout or other measures which facilitate bus services, such as dedicated bus lanes, studies to give buses priority at intersections and can’t be used for landscaping or public amenities, which in France, is an important concern when one is planning for rapid transit.