Escalating energy costs are placing financial pressures on higher education estates, with science campuses a particular concern. Energy consumption of laboratories is around three or four times that of offices on a square metre basis, making laboratory buildings responsible for between 50% and 80% of the total energy- related (non-residential) carbon emissions of research-intensive universities. However, there are a number of measures that can be taken to reduce science campus energy consumption without compromising health and safety or the integrity of research.

1. Initially, explore whether air change rates for the air conditioning systems on campus could be reduced (with the provision of local overrides) at the weekend, or overnight, when the laboratories are unoccupied.
2. Identify whether air change rates are higher than necessary in specific zones. Often air change rates are set on a site- wide basis and could be reduced safely in some low risk areas of the site.
3. Fume cupboards are major energy- consumers. A 900 mm wide fume cupboard with a maximum sash height of 500 mm and face velocity of 0.5 m/s extracts approximately 225 l/s of conditioned air from the room. This higher than average demand for conditioned air has a significant knock-on effect across the site, driving up the energy consumption of air conditioning system components such as air handling units, chillers and fans. As a priority, ensure that fume cupboards have variable air volume (VAV) capability to reduce air extraction automatically when sashes are closed. For the example above, extraction of conditioned air drops from 225 l/s to just 55 l/s when the sash is down, reduces the requirement by 170 l/s. So transitioning older fume cupboards from constant to variable air volume has significant energy saving potential.
4. Consider installing a room air management system, such as the TROX EASYLAB system, to make significant reductions in energy consumption. These systems automatically control all supply and extract air for the laboratory to ensure that the required ventilation strategy is maintained. Integrating the air management of the room with that of the fume cupboards (or other technical extract) to automatically balance and offset changing requirements, reduces the total supply and extract volumes. For example, if the fume cupboards are open and extracting air, there is not the same requirement for the room system to carry out this process. By scaling down room exhaust air extraction in line with fume cupboard extraction, the room air management system is able to prevent over-supply and extraction of conditioned air from the space, improving energy efficiency significantly.
5. Introduce devices to close the sashes of fume cupboards automatically when they are not in use. It is very common for students to leave sashes up whilst they are away from the fume cupboards, wasting energy. Automatic systems, based on presence detection, can prevent this.
6. Investigate whether fume cupboards can be made more energy efficient by retrofitting new control technology into existing cabinets, or activating features that are currently unused.
7. Look into local cooling or extraction devices such as ventilated down flow tables, canopy hoods or fume exhaust ‘snorkels’. These can reduce loading on the site’s central air conditioning facilities by taking heat away at source.

www.troxuk.co.uk