Evaporative Cooling Case Studies
Air Handling System - Fitness Centre
Cardiff Met is one of the leading universities for student sport in the UK offering excellent sports facilities and an extensive range of activities to cater for everyone from elite athletes to students, staff and the wider community
This building like all gyms needs to be kept cool in hot weather, warm in cold weather and ventilated correctly to prevent the buildup of CO2. In normal conditions where C02 levels are not measured, building regulation guide lines state that there must be 10 litres per second of air per person entering the building. This equates to over 1000 litres per second in a gym this size which, can cater for 100 people. At a required design temperature of 20C inside when the outside temperature is 0C it takes 2kW of central heating to heat the air that is coming in, to get it to the correct temperature.
The EcoCooling system minimises the heating energy by measuring the CO2 in the building at all times, bringing in air only when the CO2 levels rise over 1000ppm. This avoids unnecessary heating. External air is heated using a radiator system at the point of entry inside the gym and this air is then re-circulated to keep the chill off the building when there are only a few occupants. 2 large fabric ducts stretching the length of the gym distribute the air draft free into the gym maintaining consistent conditions.
As occupancy increases CO2 levels rise with the rate of the rise dependent upon occupancy. Only when the level reaches 1000ppm is fresh air brought into the building by opening the dampers. This air is mixed with the hot air to provide air at the correct temperature to enter the gym. By using this method the minimum amount of energy is used on heating. When the air no longer requires heating the radiator is switched off automatically and the hot air is extracted through the extract fans on the side wall of the gym again saving energy.
As occupancy increases the heat load in the building goes up along with the cooling requirement. The introduction of fresh or evaporatively cooled air therefore coincides with the need to increase C02 levels making the system even more efficient.
Refrigerant free and using only 50/60W of electricity, the system is controlled using a Crouzet/Schneider PLC designed by EcoCooling. An added advantage of this system is that during busy times odours are expelled out of the building with the hot air.