A study into the extent of oversizing in 50 HVAC systems.

BSRIA are currently conducting a research project aimed at promoting identification and amelioration of plant oversizing, with particular emphasis on providing assessment of potential energy savings achievable through the application of remedial measures. The objective of the project is to update existing BSRIA guidance, which will provide building operators with information on how to identify excess HV AC plant capacity and how to enhance the performance of such plant. The publication will highlight the extent of oversizing found in 50 UK sites, whilst additional case studies will look at the savings achieved on sites where action has been taken to ameliorate the issues associated with oversized plant. 50 HVAC systems have been monitored and the extent of plant oversizing established through analysis. It was found that 80% of heating plant, 56% of ventilation plant, and 100% of chiller plant incorporated capacity in excess of that required to meet design conditions. This paper presents the findings of these 50 initial case studies and a description of the monitoring and analysis techniques that were used.