Energy In Buildings & Industry Article Sept

As both the financial and environmental costs of refrigerant-based cooling come under close scrutiny there are very good reasons for considering alternative technologies, says John Barker

The cooling effects of evaporating water have been known for thousands of years and used to good effect in a wide range of applications. In more recent decades this ‘low-tech’ approach has been superseded by refrigerant-based cooling, bringing with it a considerable increase in energy consumption – plus the additional environmental impact of using refrigerants.

Now, however, evaporative cooling is not only making a comeback but it has also gone ‘high-tech’ in the form of modern adiabatic humidifiers.

All forms of adiabatic humidification use less energy than steam humidifiers, though there is quite a lot of variation within the adiabatic category. For instance, low-pressure nozzles use pressurised air to atomise the water so energy is consumed by the air compressor. High- pressure nozzles, on the other hand, take the energy for atomisation from high pressure water, so here the high- pressure pump is the main energy consumer. Ultrasonic humidifiers have low energy consumption but also very low outputs.