Two new IIR Informatory Notes on Energy Recovery!

The IIR has just published two new Informatory Notes on energy recovery: one on Energy Recovery in Mechanical Ventilation Systems and the other one on Air-to-Air Energy Recovery Equipment. 

The thermal loads of buildings, apart from internal gains, can be classified into two main categories: losses or gains through the envelope and ventilation loads. Ventilation loads are becoming more important as air purity standards, and thus fresh air supply rates, are increasing. Heat recovery from exhaust air can strongly reduce these loads by pre-heating or pre-cooling the fresh inlet air. Heat recovery in a ventilation system allows significant energy savings, particularly when outdoor conditions differ greatly from indoor ones. Moreover, when a recovery system is provided, the installed capacity for heating and cooling can be greatly reduced. 


  • The IIR Informatory Note on Energy Recovery in Mechanical Ventilation Systems analyses the possible energy, environmental and economic benefits of this technology depending on the climate in which the building is located. It concludes that heat recovery in mechanical ventilation systems may reduce the usage of fossil fuels, with payback periods of one or two years. 


  • The IIR Informatory Note on Air-to-Air Energy Recovery Equipment describes the performance, characteristics and operating modes of the great variety of appliances available for use in building ventilation heat recovery or in process-to-process industrial heat recovery. The energy benefits of heat recovery can allow energy cost reductions of easily over 70%. 


Summaries for policymakers outline the main conclusions and recommendations of these new Informatory Notes. Both documents are in open access. Download the IIR Informatory Notes on energy recovery in FRIDOC with the links below. The Notes are free for IIR members.