Efficient ventilation could generate 20% energy savings across Europe

In a study of air conditioning and cooling systems typically used in industry, workplaces and homes, the Fraunhofer Institute Systems and Innovation Research in Germany has come up with ways of reducing energy consumption by either modifying or replacing existing designs, or changing the way they are used. With the European energy consumption for fans estimated to be about 200 billion kilowatt hours, potential energy savings of 20% seem very attractive.

As a result of the report, Market Study for Improving Energy Efficiency for Fans, the Fraunhofer Institute is calling for the adoption of a single EU test standard and better regulations on performance and efficiency of fans. It also recommends a fan classification and labelling scheme similar to the EU Energy Label found on fridges and washing machines.

The study, co-authored by Peter Radgen of the German institute, found that some buildings make poor use of their ventilation systems. “Most of the time offices are only two-thirds full, with people away on holiday, sick leave or business, but typically all the ventilation fans are running all day long,” Dr Radgen told edie. “Sometimes the air conditioning isn’t switched off even when everyone has left the office.”

Radgen recommends installing programming devices to regulate the flow of air. For example, a CO2 monitoring device could do routine checks of the CO2 levels in a building, altering the flow rate of fans to maintain a constant level. An empty building would trigger a reduction in fan use. Other options include modifying the design or replacing old fans that curve forward with air-foiled or backward curving fans that are more efficient. Old, inefficient motors could also be replaced with modern streamlined ones.

“What we have identified is a saving of 20% in energy use for industry, which could be achieved within a two year payback period,” continues Radgen, though he warns users to calculate the financial savings from energy reductions before purchasing more expensive forms of ventilation.

A lack of appreciation of the potential savings from a system replacement appears to be one of the barriers to making the switch to more efficient air conditioning, says the report. Buyers may even be unaware that fans vary in efficiency, hence the need for more labelling.