Design and performance considerations of evaporative-pad, waste-heat greenhouses

Conference · Sun Jan 01 00:00:00 EST 1978

OSTI ID:6483577

Olszewski, M.

Rising fuel costs and limited fuel availability have forced greenhouse operators to seek alternative means of heating their greenhouses in an effort to reduce production costs and conserve energy. One such alternative uses power plant reject heat, which is contained in the condenser cooling water, and a bank of evaporative pads to provide winter heating. The design technique used to size the evaporative pad system to meet both summer cooling and winter heating demands is described. Additionally, a computational scheme that simulates the system performance is presented. This analytical model is used to determine the greenhouse operating conditions that maintain the vegetation in its thermal comfort zone. The evaporative pad model uses the Merkel total heat approximation and an experimentally derived transfer coefficient. Energy balance considerations on the vegetation provide a means of viewing optimal vegetation growth in terms of greenhouse environmental factors. In general, the results indicate that the vegetation can be maintained within its thermal comfort zone if sufficient warm water is available to the pads and the air stream flow is properly adjusted.

• Research Organization: Oak Ridge National Lab., TN (USA)
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 6483577
• Report Number(s): CONF-781202-24
• Resource Relation: Conference: ASME meeting, San Francisco, CA, USA, 10 Dec 1978
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
20 FOSSIL-FUELED POWER PLANTS
GREENHOUSES
PERFORMANCE
WASTE HEAT UTILIZATION
THERMAL POWER PLANTS
WASTE HEAT
COOLING
DESIGN
ENERGY CONSERVATION
EVAPORATION
MATHEMATICAL MODELS
SPACE HEATING
BUILDINGS
ENERGY
ENERGY SOURCES
HEAT
HEATING
PHASE TRANSFORMATIONS
POWER PLANTS
WASTE PRODUCT UTILIZATION
WASTES
320104* - Energy Conservation
Consumption
& Utilization- Commercial & Industrial Buildings- (-1987)
200105 - Fossil-Fueled Power Plants- Heat Utilization