Evaporative cooling systems work by making use of the atmosphere’s free latent energy. Water from the mains supply is brought into a cooler, pumped to the top and then dispersed over pads in a continuous flow, saturating them.

Once the pads are saturated, air is drawn through them. As the water in the pads evaporates, it draws latent heat from the air and cools the air flow. This cool air is distributed around a building via ducts and cools the building using axial fans.

The cooling effect is greater the higher the outdoor temperature. The evaporative cooling can lower air-flow temperatures by up to 15 degrees Celsius. Most such cooling systems in Britain maintain the air-flow temperature below 23 degrees Celsius, effectively turning a summer day into spring. During extended periods of hot weather, evaporative cooling will be able to keep building temperatures below 25 degrees C.

Evaporative cooling is very energy-efficient. In can use up to 85 per cent less energy than an air-conditioning unit providing the same cooling effect. Britain is a relatively cold country, so there is little economic sense in keeping an air-conditioning unit running all of the time. During cool weather, the evaporative cooling set-up may be used as a ventilation system and revert to a cooling system during hot weather.

Ambient air keeps the building cool most of the time. A relatively low air-flow rate is required to keep the system running, while the energy consumption by the fans can be minimised using a control system.


Fields marked with a * are required