Feasibility of Thermoelectrics for Waste Heat Recovery in Conventional Vehicles

Technical Report · Wed Apr 01 04:00:00 EDT 2009

DOI:https://doi.org/10.2172/951806· OSTI ID:951806

Smith, K; Thornton, M

Thermoelectric (TE) generators convert heat directly into electricity when a temperature gradient is applied across junctions of two dissimilar metals. The devices could increase the fuel economy of conventional vehicles by recapturing part of the waste heat from engine exhaust and generating electricity to power accessory loads. A simple vehicle and engine waste heat model showed that a Class 8 truck presents the least challenging requirements for TE system efficiency, mass, and cost; these trucks have a fairly high amount of exhaust waste heat, have low mass sensitivity, and travel many miles per year. These factors help maximize fuel savings and economic benefits. A driving/duty cycle analysis shows strong sensitivity of waste heat, and thus TE system electrical output, to vehicle speed and driving cycle. With a typical alternator, a TE system could allow electrification of 8%-15% of a Class 8 truck's accessories for 2%-3% fuel savings. More research should reduce system cost and improve economics.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO.
• Sponsoring Organization: USDOE
• DOE Contract Number: AC36-99GO10337
• OSTI ID: 951806
• Report Number(s): NREL/TP-540-44247
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
33 ADVANCED PROPULSION SYSTEMS
ADVANCED VEHICLE SYSTEMS
ECONOMICS
EFFICIENCY
ELECTRICITY
ENGINES
FUEL CONSUMPTION
SENSITIVITY
TEMPERATURE GRADIENTS
THERMOELECTRICS
Transportation
VEHICLE FUEL ECONOMY
VELOCITY
WASTE HEAT
WASTE HEAT RECOVERY