Q&A: A breath of fresh air

We talk to Engineer Chris Jones from Flakt Woods about ventilation and energy efficiency in schools

Posted by Stephanie Broad | August 25, 2016 | Facilities & buildings

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• #energy-efficiency
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• #school-buildings
• #interview
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What impact does a well-ventilated school building have on learning? 

It’s well documented that children will be better suited to learning in an environment with good indoor air quality. CO2 levels have a direct effect on a person’s ability to concentrate and learn. When CO2 levels are too high we get headaches, feel tired and in some extreme cases become seriously unwell. It is also important to ensure enough filtered fresh air within a space to reduce pollutants in the air and minimise sickness amongst pupils. Cold draughts must be avoided so children don’t become uncomfortable or unwell and this can be a problem with naturally ventilated schools. Schools that only use openable windows for ventilation also may suffer ingress of noise from external sources, this could lead to the teacher straining their voice or the children simply not being able to hear what the teacher is saying. 

How can energy efficiency products boost a school’s reputation? 

People are becoming more aware of the impact we’re having on the environment and the appeal of a low carbon school will attract a lot of prospectus parents due to the many benefits it offers. When schools implement energy saving measures it not only improves learning conditions, resulting in better grades, but also saves money which can be better spent on the children’s educational needs. A school that is aware and teaches the social and environmental advantages to reducing energy consumption can offer great insights to the next generation of energy users. 

How does your ventilation package, eCO Premium, reduce carbon emissions? 

Using highly efficient EC fans with low specific fan powers means we use less electricity than traditional AC motors. Speed control is automatically built into the motor itself and therefore no need for an additional inverter. With this automatic speed control we can modulate the fans via a CO2 sensor for example, the more children within the classroom the more fresh air we introduce, and as children leave the fans slow down. The third fan law states that if you halve your fan speed you reduce your power consumption to an eighth, so you can imagine the amount of electricity we can save with this technology. With filter monitoring we can alert facilities management companies when the filters are dirty and need replacing – this will stop the fans wasting energy as they increase in volume to overcome the dirty filter build up. Finally, with a counter-flow heat exchanger we can recover between 80-90% of wasted heat from the space – we extract the warm stale air from the classroom and use this to heat the incoming cold fresh air. There is no cross-contaminations of airflows and we ensure good air quality and avoid cold draughts. This means in many classrooms that no additional heating is required.

How easy is the system to install and maintain?

Premium only needs a single phase supply and ductwork connections and can be installed outdoors our within a false ceiling. The filters are the only thing that needs to be maintained and this helped with filter monitoring via our controls as mentioned above. The filters are accessed via easy screw-off panels which don’t require a hand tool. If the heat exchanger needs to be removed to be cleaned this comes in two sections making it easier to handle and is made of aluminium so is light – essential when working at high level.  

What new products and innovations do Flakt Woods have for the future? 

Flakt Woods are always looking to develop and improve existing products and increase energy efficiency. With new European legislation (the Eco Design Directive) this has become very important to reduce CO2 emissions as much as possible whilst maintaining a high standard of IAQ. We manufacture larger AHUs and these can be used to in schools also to serve multiple classrooms. A type of unit that is popular is a modular AHU with indirect cooling. This uses an adiabatic humidifier to cool the extract airstream before it passes through the heat exchanger and increases the amount of cooling recovery we can achieve. This uses tap water and can be a cheaper alternative to having mechanical cooling via a VRF split system or chilled water via a chiller. 

www.flaktwoods.co.uk