UC Riverside to Conduct Hybrid Construction Emissions Study

October 19, 2011

The California Air Resources Board (CARB) has awarded the Center for Environmental Research and Technology (CE-CERT) a $2 million grant to evaluate emission reduction benefits of hybrid technology for heavy-duty off-road construction vehicles. CE-CERT is part of the University of California-Riverside.

This is part of a larger effort by CARB to expand the use of hybrid technology to help meet the goals of AB 118— to achieve an 80 percent reduction of greenhouse gas by 2050. The use of hybrid-electric technology in heavy-duty on- and off-road vehicles is at a very early stage of development. Through the recent Hybrid Truck and Bus Voucher Incentive Project (HVIP), more than 650 hybrid trucks and buses have been deployed.

Hybrid technology can provide fuel efficiency benefits of 5 to 20 percent, and potential emission reductions between 25-70 percent. Little is known about the potential benefits of hybrid technologies for construction equipment because of their unique and diverse duty cycles when used in real world applications.

The behavior of hybrid equipment, like excavators and bulldozers, will be characterized on a second by second basis, during in-use operations at construction sites. This includes measurements of vehicles’ emissions using Portable Emissions Measurement Systems, and to measure their “activity.”

Previous work at CE-CERT has shown activity data and emissions data profiles are quite different for various actions, such as digging, lifting, rotating, pushing, moving and transporting materials.

The project will help establish the methodology for making comparisons under such varied conditions. It will also consider the differences between emerging hybrid implementations by leading manufacturers.

The study may be useful in establishing future inventories —data that could contribute to a basis for hybrid incentives under AB 118 programs.