Non-engine losses such as wind resistance and drag, braking, and rolling resistance can account for up to a 45% decrease in efficiency for heavy-duty vehicles. The Vehicle Technologies Office (VTO) supports research and development (R&D) to minimize these and other sources of energy loss, including: friction and wear in the power train, thermal (heat) loads, operation of auxiliary loads (air conditioning, heaters, refrigeration, etc.), and engine idling. This work both identifies and tests methods that may reduce energy losses. Once researchers identify methods that may reduce energy losses, they then prototype these promising technologies, and test them onboard heavy vehicles in the laboratory. If these technologies are validated, researchers test them on the road to obtain durability, reliability, and life-cycle cost data.
This process for validating performance, component robustness, operational reliability, and cost-competitiveness — conducted in conjunction with prominent participants in the heavy vehicle industry through research and development with the U.S. Department of Energy — is most likely to provide a basis for timely introduction of a technology into the marketplace and acceptance by industry.
Current areas of focus for the parasitic loss reduction activity include:
- Aerodynamic drag reduction research, to characterize and respond to energy losses caused by wind and rolling resistance.
- Friction and wear-reduction research, to understand and address the multiple surface interactions that occur in heavy vehicle systems.
- Predictive cruise control that can control vehicle speed for optimal fuel efficiency.
- Idle reduction devices and systems that enable truckers to turn off their engines when stopped and still be comfortable while sleeping.
- Thermal management to counter some of the negative heat-producing consequences of emissions control techniques.