Improving the energy performance of residential clothes dryers

Conference · Wed Feb 01 04:00:00 EST 1984

OSTI ID:6972604

Hekmat, D; Fisk, W J

Experiments were conducted to evaluate four techniques to improve the energy efficiency of electrically-heated domestic clothes dryers. Reduced air flow rate and heater input led to energy savings around 8%, while recirculation of a portion of the exhaust air back into the clothes dryer reduced energy consumption by approximately 18%. These two measures are attractive because of their low cost. Two modes of using an air-to-air heat exchanger for heat recovery were considered. The first is to preheat the inlet air with heat from the exhaust air, which resulted in 20 to 26% energy savings. The second mode is 100% recirculation of air through the dryer and a heat exchanger and condensation of water from this air in the heat exchanger by using indoor air as a heat sink. This resulted in 100% heat recovery (i.e., all heat was rejected to indoors) but the energy consumption of the dryer was increased by up to 6%. To maximize energy savings, a clothes dryer with a heat exchanger can be equipped to operate in the preheating mode in the summer and in the recirculation/condensation mode in the winter. The last measure investigated recirculation, through a heat pump (i.e., dehumidifier), also resulted in a 100% heat recovery and, in addition, up to a 33% reduction in dryer energy consumption, but this technique also yielded long drying times.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6972604
• Report Number(s): LBL-17501; CONF-8405181-1; EEB-Vent-84-4; ON: DE84012574
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320101* -- Energy Conservation
Consumption
& Utilization-- Residential Buildings-- (-1987)
AIR FLOW
APPLIANCES
CLOTHES DRYERS
DRYERS
EFFICIENCY
ELECTRIC APPLIANCES
ENERGY CONSUMPTION
ENERGY EFFICIENCY
EQUIPMENT
EXHAUST RECIRCULATION SYSTEMS
EXHAUST SYSTEMS
FLUID FLOW
GAS FLOW
HEAT EXCHANGERS
POLLUTION CONTROL EQUIPMENT