By Harvey McEwan Though most commonly associated with power plant usage, cooling towers are actually employed across a wide variety of industrial and commercial platforms. Essentially, they provide heat removal from a range of environments, from oil refineries to residential homes. The basic process incolves the extraction of heat from water cooling systems and the subsequent release of that heat into the atmosphere. This process is referred to as “evaporative” heat rejection. The use of a cooled water stream is far more cost and energy efficient than an air dryed or dry heat rejection process, the latter of which is demonstrated by a car radiator. In simple terms, it is akin to someone pouting cold water on a hot frying pan; the cooled water rapidly decreases the temperature of the pan, and the evaporated water is senn rising from it straight away. Cooling towers are often used to provide cooled water for such systems as air conditioning and electric power generation. Whilst they are most often seen to be up to 200 metres tall and situated adjacent to power stations, they can also be found in a more residential setting, providing heat reduction for only a few gallons of water per minute. In contrast, hundreds of thousands of gallons per minute can be handled in a power plant setting. There are various types of cooling towers available depending upon the needs of the heat producing body. Smaller cooling tower applications may only require an HVAC (Heating, Ventilating, and Air Conditioning) model, which comprises of a cooling tower and water cooled chiller. HVAC systems also use water source heat pumps which share a common piping “water loop”. For larger scale operations such as petrol refineries, chemical plants and power stations, industrial cooling towers are employed. By utilising a cooling tower in this situation, the need to continuously discharge vast amounts of water to the ocean – or whichever body of water it was taken from – is removed. Instead, the water is evaporated into the atmosphere. Whilst some coastal plants do make use of the water supply to hand in this very way, further implication regarding the environmental effect of the water waste have to be considered, and stringent precautiouns must be put in place. The use of cooling towers as a means of temperature control is a highly efficient one, both in terms of cost and energy. It is no wonder then that this is a trusted method across the globe, and has been since its initial inception back in 1918, when the hyperboloid cooling tower was patented by Frederik van Iterson and Gerard Kuypers. Harvey McEwan writes to offer information amd advice on a variety of areas. Read through Harvey’s other articles here to find out more.