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Montebello, CA to Buy 150 ISE Gasoline Hybrid-Electric Buses

New Flyer-ISE gasoline hybrid for Montebello.

The Board of the City of Montebello, CA has authorized the purchase of 150 40-foot gasoline hybrid-electric buses, to be supplied by the team of New Flyer and ISE Corporation.

This is a Federal Transit Administration pooled procurement program that provides 90% federal funding to participating agencies. ISE will provide its ThunderVolt gasoline hybrid drive system. (Earlier post.) New Flyer of America will be the vehicle manufacturer.

Montebello Bus Lines (MBL) is the municipal bus operator serving East Los Angeles, Commerce, and the City of Montebello, and is the leading agency in this 7-agency pooled procurement program. The other participating agencies are Norwalk Transit System, El Dorado Transit Authority, Fresno Area Express, Long Beach Transit, Napa Valley Transit, and Torrance Transit.

The hybrid buses will feature ISE’s ThunderVolt gasoline hybrid drive system, which was certified as an alternative fuel system by the California Air Resources Board (ARB) in November 2003. More than 100 of these hybrid buses are already in revenue service in various California cities, including Long Beach, Orange County, Norwalk, Montebello, Gardena, San Bernardino, and Fresno. Currently operating ThunderVolt gasoline hybrid-equipped buses have exceeded 4 million miles of total revenue service, with availability of 97% at the largest fleet in Long Beach.

Components of the gasoline hybrid cradle. Click to enlarge.

The series hybrid drive uses a Ford ULEV 6.8-liter V-10 gasoline engine mated to a 650V, 150 kW Siemens ELFA generator and motor system. The dual drive motors each deliver 85 kW (114 hp) of power and maximum torque of 450 Nm (332 lb-ft). Energy is stored either in an ultracapacitor or a nickel sodium-chloride (Zebra) battery pack.

The hybrids deliver fuel economy of 3.5 to 4.5 mpg, with a typical range of around 300 miles. The bus can operate on battery power alone for 5–15 miles and in emergency situations. Regenerative braking recaptures up to 30% of daily operating energy.

At the recent ARB ZEV hearing, ISE Chief Scientist Paul Scott noted that ISE is also working with Altairnano on future li-ion battery packs in the context of hydrogen buses.

ISE will be delivering the new hybrid systems to New Flyer over the next 5 years.



Go one more step and make them CNG hybrids and you get a really clean bus. Not hard to do and would make a big difference.


CNG has no intrinsic advantage over current diesel technology. It is not cleaner, CNG has less BTU content than diesel fuel, CNG is more expensive from infrastructure standpoint, less reliable and inherently more dangerous.

Bud Johns

They didn't mention why they chose a gasoline engine. Why am I a little baffled?


Because gasoline engines are cheaper and because fixes such as direct injection may improve efficiency comparable almost to diesels I was told.


"Because gasoline engines are cheaper and because fixes such as direct injection may improve efficiency comparable almost to diesels I was told."

They are cheaper but less durable, and the potential of GDI is just that at this point.

Gas makes sense for pollution reasons, but not GW/PO reasons. Of course, this particular fleet of buses represents only a miniscule fraction of total oil used in the US or the world, so it's not a big deal.

John Baldwin

CNG buses available today in Europe meet the EEV standard which is far ahead of diesel. Also, if you use bio-methane (as the 228 CNG buses in Lille), you run on a fuel with ZERO carbon dioxide!

You can't beat that.


from an earlier article in 2006...
Elk Grove Struggles with Hybrid Buses on Freeways

“Hybrid may not be the way to go for commuter service,” said e-tran Transit Manager Carlos Tobar, who was hired to run e-tran more than a month after the start of the new service. ”Live and learn.“

So, what’s the problem with the hybrids? They perform best during stop-and-go traffic, Tobar said. The hybrid’s electric energy booster, an ultra capacitor, works in tandem with a 145-kilowatt generator. That booster is recharged every time a driver applies the brakes.

That’s great for intercity transit, but is troublesome on freeways where brakes are less often applied.
“At highway speeds, many of the systems are stressed,” Tobar said.

Elk Grove’s hybrids are remanufactured by Complete Coach Works, using a gasoline series-hybrid powertrain from ISE Corp. The 17-bus e-tran fleet was to be the country’s first 100% hybrid commuter bus fleet.

The ISE powertrain uses a Ford ULEV 6.8-liter V-10 gasoline engine mated to a Siemens ELFA generator and motor system. The dual drive motors each deliver 85 kW (114 hp) of power and maximum torque of 450 Nm (332 lb-ft).


Even with low sulfur diesel, I can not imagine a diesel fueled engine having cleaner tailpipe emissions than a CNG engine. I have no proof, but would like to see some.


The Honda GX CNG Civic is the cleanest car that Honda makes and they make some mighty clean cars. So I do NOT see why making this bus CNG would not make it cleaner.


6.8-liter V-10 !! WTF is up with that?
DaimlerChrysler has a three axle articulated hybrid bus that runs on a 4.8L diesel.

DaimlerChrysler Developing Series Hybrid Citaro Bus


Isn't this a step backwards? How does this wean us from
M.E. oil?


Most buses are smelly and dirty, and these buses still run on gasoline. Can't we just improve on the old electric
trolleys? They had to be ahead of their time compared
to these soot-belching monsters we have now.


CNG would be cleaner, but the return on clean tech, purely in terms of emissions, decreases as you compound technologies. At a point your return on investment is low and you've made too complicated a marriage of new technologies to have success.

Also, CNG requires a fueling station that cost about 5 million. Achieving economically efficient clean emissions without CNG is what these buses do.

I think that its a step forward in a long journey towards zero emission buses. Making a cleaner, efficient vehcile that can be introduced to the market is better than making a zero emission vehicle that costs the price of ten vehicles...right? We will need to start with adaptive technologies that can operate within our current infrastructure.

The same company has built a CNG hybrid in San Diego

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