First Large Transit Order for ThunderVolt Gasoline Hybrid-Electric Drive System

Electric Vehicle Product Update from ISE Corporation
Volume III, Issue 2 * 2003.05.01

LONG BEACH, CA - On 28 April 2003, the Long Beach Transit Board of Directors authorized the purchase of New Flyer transit buses using a new gasoline-powered hybrid-electric drive system developed by ISE Research-ThunderVolt (ISE). Long Beach approved an initial purchase of 27 buses using this drive technology, but with options and "piggyback" orders from other California transit agencies, the total number of buses purchased over the next four years is expected to be well over one hundred. This makes the Long Beach order the second largest purchase of hybrid buses in U.S. history, as well as the first volume purchase of hybrid buses usinggasoline fuel.

The ISE gasoline-hybrid drive system generates electric power with a Ford Triton V10 engine mated to a Siemens permanent magnet generator. The Ford engine is ultra-low emission ("ULEV") rated, and produces even lower emissions when used as an element of ISE's advanced "ThunderVolt-ELFA" series hybrid drive system. In this drive configuration, the engine is operated in its most efficient, cleanest-burning power range, and a deep-cycle battery pack is used to provide surge power and capture regenerative braking energy. In tests conducted by the California Air Resources Board (ARB) in 2002, a prototype New Flyer bus (pictured below) using an early variant of this drive system was shown to produce approximately 0.6 grams/mile of oxides of nitrogen (NOx). Near zero particulate matter was also measured by West Virginia's Mobile Heavy Vehicle Emissions Testing Laboratory. As indicated in the graph, these are substantially lower emissions than produced by any other bus of this size in service in the U.S., including natural gas fueled buses and competing hybrid configurations using diesel fuel.

     Prototype New Flyer-ISE gasoline-hybrid bus of the type ordered by Long Beach Transit.

The bus tested by the ARB is the first of three prototypes developed by ISE for Omnitrans in San Bernardino. In service with Omnitrans since September 2002, this bus has achieved 5.5 miles per gallon in revenue service. Accounting for the difference in fuel energy content, this significantly exceeds the fuel efficiency of urban transit buses using diesel fuel on the same route.

Encouraged by the low emissions and high fuel economy of the New Flyer-ISE prototype bus, Long Beach identified gasoline hybrid technology as an acceptable option in a competitive solicitation released by the agency in late 2002. New Flyer teamed up with ISE to offer 40-foot low floor buses equipped with the gasoline-powered ThunderVolt-ELFA hybrid drive system. The solicitation immediately attracted strong interest in the industry, and a half dozen other California transit agencies have expressed interest in "piggybacking" orders for the New Flyer-ISE hybrid on top of the base Long Beach order. ISE is working with the ARB and Ford to make this the first ARB and EPA-certified hybrid drive system. Altoona testing of the bus is also planned. "Long Beach Transit is proud to be at the forefront of promoting clean-burning, efficient hybrid-electric drive technologies," according to Jim Ditch, Executive Director of Maintenance and Facilities for Long Beach Transit. Ditch cited other agencies seeking to piggyback on the Long Beach order as evidence that gasoline hybrid technology is already gaining widespread industry acceptance. In addition to producing very low emissions and achieving high fuel efficiency, the use of gasoline eliminates the cost and complexities involved with alternative fuels such as CNG.

The ThunderVolt-ELFA hybrid system achieves these results, while maintaining high reliability, by combining proven components with ISE's advanced hybrid control system. The system uses Siemens "ELFA" motors, motor controllers, and generators. These are the most proven hybrid bus components in the world, having been used in more than 600 buses in Europe.

Also utilized are nickel sodium-chloride batteries, which have a higher energy density than the lead acid and nickel metal hydride batteries used in competing hybrid drive systems. ISE's "series" hybrid architecture, also compatible with diesel and hydrogen fuel, is ideally suited to urban transit bus duty cycles, and offers a particularly large advantage over competing "parallel" hybrid systems.

Funding to support development, testing, and commercialization of the ISE gasoline hybrid system was contributed by Omnitrans, CALSTART/WestStart, the Federal Transit Administration, U.S. Department of Defense, California Office of Strategic Technology, California Energy Commission, CALTRANS, South Coast Air Quality Management District, City of San Bernardino, and San Bernardino Association of Governments.