Roof Pond Cooling System

In both processes the roof acts as a heat exchanging element which is cooled by evaporation on its surface longwave radiation to the sky 1 or both.

Roof pond cooling system.

Exposure of the water pond to the night sky for cooling. Roof ponds provide cooling benefits through indirect evaporative cooling and or radiant cooling 19 22 23 24 25 26. In the simplest form this involves placing a pond on the building roof. Comparing performance relative to other passive strategies showed that in many cases roof pond cooling systems are about equally effective in maintaining indoor thermal comfort.

Roof ponds with wet gunny bags shaded roof ponds ventilated roof ponds and roof ponds with movable insulation proved to be more effective relative to other variants of roof pond cooling systems. A more refined method involves insulating the pond during the daytime to prevent solar gain. What is roof pond roof pond is a passive cooling technique based upon the increased heat capacity of cheap and widely available water. Also called an evaporative cooling system a roof misting system lowers surface temperatures by spraying an extremely small amount of water across the roof allowing the water to cool the roof as it evaporates.

With these elements a roof pond can contribute to thermal comfort in all seasons. As water evaporates from the pond heat is consumed. The main aims were to gain a detailed understanding of different roof pond configurations and their performance compare effectiveness of. Overall 19 roof pond cooling and 4 roof pond heating systems were identified.

H2o sun 3. This review suggests that in some cases roof ponds can provide year round thermal comfort while reducing demand for. To demonstrate a roof pond system that uses water and sun to heat and cool without electricity. Evaporation in a pond is proportional to the air water contact area.

In general the pond is covered during day to prevent heating and open at night to be cooled. During the day water in the pond absorbs heat cooling the ceiling below. An indirect gain design which provides both heating and cooling is the thermal pond approach which uses water encased in ultraviolet ray inhibiting plastic beds underlined with a dark color that are placed on a roof. This cools the roof which acts as a heat sink and absorbs heat from the interior of the building.