Plant & Works Engineering
Humidity’s hidden impact
Published:  13 June, 2019

The UK is once again facing some recording-breaking temperatures this summer. And so the main question on everyone’s minds will soon be, how do we keep our workplaces cool and comfortable, without wasting money, energy or resources? It’s a question that comes up every year. Humidity Solutions spoke to PWE to give some inside info on how to keep your environment cool by remembering one important factor – humidity.

The relationship between temperature and humidity (along with the relationship between humidity control and good air quality) is something that’s often overlooked in the world of heating and cooling, being left out of specifications for new installations 8 times out of 10. But it’s one of the most important factors in determining how comfortable people are in your environment.

Think about it. When it gets really humid in this country, you can feel hot, clammy and uncomfortable in your own skin – and much warmer than the actual air temperature. That’s because the comfortable and acceptable relative humidity range for humans is around 40-60%. If it goes above this level, people start to feel uncomfortable and out of proportion with the actual indoor temperature. This leads to distraction, difficulty concentrating irritability and lots of instances of ‘turn the cooling systems up’, increasing your energy consumption.

At the other end of the spectrum, relative humidity below 40% makes people feel colder than the actual temperature is. They will shiver, struggle to get comfortable, and – you guessed it – they’ll turn the heating up, once again increasing your energy consumption. Lower relative humidity can also cause health problems for you and your employees, including higher susceptibility to coughs, colds and other viruses, sending our absenteeism rate skyrocketing.

Now, your workplace’s natural relative humidity will be somewhat determined by your environment. Newer buildings that are more airtight rely on mechanical ventilation, and so are easier to control, and will usually have a lower RH. Older, ‘leaky’ buildings will be more influenced by the variations of humidity from outdoors, since air tends to leak in and out. One of the biggest problems in the UK is low RH, particularly in winter, where heating systems send the RH through the floor.

The ideal solution to all of the above? Install a humidifier.

The Impact of humidification

Humidification is essentially the process of adding moisture into the air to achieve the desired humidity balance. This can be done in a number of ways, but the most popular (and traditional) approach is still to heat water to produce steam. There are a number of different ways to do this depending on your project, budget and environmental concerns. But clearly in a carbon-conscious world there is an appetite for solutions that use less energy than these traditional steam solutions. And so we’re seeing an increase of high pressure, low energy systems using cold water. These are perfect for conserving energy and can be easily installed to existing buildings of all ages.

These systems work by injecting water into the air under pressure through multidirectional, fan assisted nozzles. The pressure ensures the water is atomised and absorbed quickly into the air – within 1.5m of the nozzle itself. These systems can be used on ceiling heights as low as 2.4m, with nozzle heads the size of a CCTV camera, making them the perfect option for almost any property.

A key benefit of this approach is that it uses cold water, so there is no extra energy needed to heat the water. For every 500 litres of water that’s evaporated the system provides around 345kW of cooling power for just 4kW of input. Not only that, but the quick absorption into the air (known as adiabatic humidification) also has a free-cooling effect, which reduces the load on comfort cooling systems and increases energy efficiency.

With a system like this, you can simply and effectively alter the air quality, temperature and humidity of your environment. But installing the right solution for you requires some knowledge of how to alter the properties of the air, and the various options available to achieve optimum comfort. At Humidity Solutions, this is exactly what we do. We use years of experience to create a bespoke solution that’s tailored to your needs.