Søren Aggerholm

Calculation of building heating demand in EPIQR

Calculations of energy requirements for space heating in EPIQR are based on an existing computer programme, made according to the European standard EN 832:1998. The programme was originally a stand-alone programme with its own user interface. This has been stripped of and the source code re-compiled into a dynamic link library (DLL) controlled by EPIQR. The method is based on a monthly calculation of heat losses and usable heat gains for the building. For the calculation, the monthly mean values of the external temperature and solar radiation are applied, and the heat gain from lighting and appliances, as well as the heat-accumulating capacity of the building, are taken into consideration. In EPIQR, some input parameters have been fixed to ensure that the user only has to supply simple input data to carry out a heating requirement calculation. This paper describes the applied calculation technique and the assumptions made in EPIQR to carry out heating requirement calculations and how energy-saving retrofit is evaluated using the software.

Control of Hybrid Ventilation Systems

Abstract The paper presents examples of hybrid ventilation and control strategies in office and educational buildings from the IEA ECBCS Annex 35 HybVent case studies. The purpose is to extract the lessons learned in the case studies about the control strategy used. The conclusions are that in each building project the control strategy has to be carefully designed and operated, not only in relation to the general building design and the ventilation systems in the building, but also in relation to occupants’ habits, reactions and expectations to indoor climate and comfort. In general it is relatively easy to design a suitable control strategy for hybrid ventilated cellular offices. In landscape offices and educational buildings it is more problematic, especially with regard to the automatic central control of windows.