Altair ProductDesign Selects Parker Hannifin's Series Hydraulic Hybrid Drive System for Advanced Transit Bus Demonstrator

Altair's BUSolutions platform surpasses diesel and hybrid-electric buses in both cost and performance with Parker's hydraulic hybrid drive system.

Altair Engineering, Inc., announced it has selected Parker Hannifin's series hydraulic hybrid drive system for its BUSolutions project. The system will enable the new advanced bus platform to achieve 45-70% increased fuel economy over average diesel powertrains and more than double the fuel economy improvement of hybrid-electrics, contributing to an overall lower cost of ownership for transit authorities and reduced emissions.

BUSolutions is a collaborative effort between public and private entities to research, develop and commercialize advanced transit bus systems that, compared with conventional buses, are significantly more fuel efficient, have lower operating and maintenance costs, are competitively priced, and can operate without updating the infrastructure of existing transit authorities.

The Parker advanced series hybrid drive system is unique in that the engine is not connected to the rear wheels of the vehicle. This de-coupling of the engine from the drive wheels offers several advantages including: the ability to recover and store as much as 70% of the energy from braking, reduced brake wear, which extends brake life; an engine management system that optimizes the vehicle's engine for reduced fuel consumption; the ability to drive the vehicle with the engine off, significantly reducing carbon emissions in depots and contributing to reduced fuel consumption.

"We decided to use hydraulic hybrid technology for the bus since it recovers more than three times the brake energy and an overall 30% lower cost of ownership than any electric hybrid technology available today," said Tim Smith, director of design engineering for Altair ProductDesign. "Of all the hybrid hydraulic products evaluated, the Parker system was the clear choice because it uses well proven technologies in a system that has been tested and validated through extensive field trials. It also can easily integrate with other technologies in the bus platform and can be implemented quickly within the required timeline."

"This application of the Parker advanced series hydraulic hybrid drive system demonstrates how we have been able to deliver results far ahead of any other hybrid hydraulic system, since it also optimizes the engine speed and load for maximum fuel efficiency and lowest emissions of the bus," said Dr. Joseph A. Kovach, vice president of technology for Parker Hannifin. "Parker Hannifin is pleased to be working with Altair on the BUSolutions program. Transit buses are a vehicle segment that could greatly benefit from our hybrid hydraulic technology, and this program will allow us to prove how our technology has the potential to be used extensively within the transit bus system."

Fabrication of the first technology-demonstrator bus body structure was completed in April, and final assembly is well underway. Hybrid driveline system commissioning will be completed in mid-November, with a technology demonstration event planned for early December. Once complete, Altair will conduct testing to validate the reductions in fuel, maintenance and lifetime-operation costs. Any necessary improvements will be incorporated to ensure the design is production-ready, ensuring a smooth transition of the program into a commercialization phase.

Since BUSolutions launched in 2005, Altair has worked closely with local transit authorities, the Suburban Mobility Authority for Regional Transportation (SMART) and the Detroit Department of Transportation (DDOT), to ensure the newly designed bus platform will meet regulatory requirements and address the needs of bus drivers and riders. Altair also established the BUSolutions Advisory Board to offer insight into broader community needs, as well as perspective on actual ridership issues and public-interface ergonomics. As a result, Altair ProductDesign successfully completed the bus structure engineering incorporating design principles that will enhance the rider experience.

Additionally, BUSolutions has strategically partnered with regional and global high-tech manufacturers that will help to incorporate state-of-the-art components and technologies from the transportation sector. Program sponsors include Arvin Meritor, Parker, PRAN, Sika Corporation, Meritor Wabco, Alcoa Wheel Products, Carrier Corporation, LAAD Industries, Pretoria Transit Interiors, Shaw Development, Tenneco, USSC Group and Williams Controls.

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