At our recent CPD accredited evaporative cooling webinar, I received some interesting questions in the Q&A session at the end. I would like to share my answers, which have been edited to make them clearer.

Q: How do you deal with freezing conditions?

A: During colder periods, where freezing outside conditions would be expected, the evaporative coolers would not be used, and they would have been earlier drained down and isolated as part of a winterisation process. This means that there is no chance of any water freezing inside the unit, as it contains no water.

Freezing conditions are then dealt with by carefully mixing quantities of that cooler outside air with warmer waste air from the IT equipment, therefore providing air at desirable conditions.

Data centres are thirsty for electricity, most of it used for maintaining temperature and humidity within the maximum and minimum levels that the servers need to operate properly. This also means that data centres tend to have a big carbon footprint. However, it need not be so: evaporative cooling provides a very cost effective and energy efficient solution to the problem. And, even though it is a water-based system, there are no health risks when it is designed correctly.

The benefits of evaporative cooling in warehouses and industrial buildings are many: it is a highly energy efficient technology, that uses no refrigerants, provides a pleasant indoor climate, is simple and easy to maintain and, last but not least, running costs are four to seven times lower than traditional air conditioning solutions – and they are even lower in data centres.

Evaporative cooling (also known as adiabatic cooling), is an extremely efficient and cost effective means of cooling. It is particularly well suited to warehouses, data centres and other industrial buildings where the manufacturing processes generate relatively high levels of heat.

If you are considering a cooling system for your factory, don’t make the mistake of focusing solely on the initial investment: consider the total cost of ownership of the system and what the critical elements which influence this are.

It is estimated that 1% of the world’s energy is currently used to cool server rooms. And this number is going up fast, as the number of data centres keeps growing, putting increasing pressure on energy supply systems and on the environment because of the consequent rise in CO2 emissions. The ICT industry is responding by moving away from traditional air conditioning systems and looking for environmentally responsible cooling solutions.

Energy efficient and environmentally responsible cooling

As a factory manager you may find that in spite of having done everything to keep your mechanical ventilation system in perfect condition, the temperature in your plant or in parts of it is getting higher. Over the years, the use of your factory building may have changed: for example, with the introduction of lean manufacturing practices, there may be a higher density of production machinery with consequent higher heat load in some areas of your facility, so that the system as it was originally designed and installed is not as effective as it used to be.

Data centres tend to be energy guzzlers, using vast amounts of power not only for running the equipment, but also for maintaining the temperature and humidity at the levels required by the servers for them to be able to operate correctly.

It’s well known that productivity at manufacturing plants plummets when temperatures persistently exceed 25C – and that’s a normal summer day. Surveys have shown that every degree above 20C can reduce productivity by as much as 4 percent. That means a rise of just 5 degrees can cut your output by an eye-watering 20 percent.

When the working environment is too hot, people work far less efficiently, morale plunges, and accidents and absenteeism rise. Cooling the factory shop floor is essential to keep productivity levels high - and for the wellbeing of the people working in this environment. But conventional cooling systems are not a viable solution: they are expensive, installation is costly, and so is the energy they use to bring the temperature down to desired levels.