Influence of occupant-depentent ventilation and heating set-points on the energy need in low-energy buildings: Virkningen av brukerbestemt ventilasjon og settpunkt for oppvarming på energibehovet i lavenergibygg

Abstract

A large proportion of the energy consumed in Europe is used to maintain comfortable indoor climate in buildings. In recent time governments around the world have implemented energy requirements for buildings, in order to reduce the energy consumption to prepare for a more sustainable future. These requirements become stricter with time, urging building-makers to develop more energy-efficient housing. The building-makers need to know the energy requirements of the building before construction begins for various reasons. To be sure the building meets the government s requirements, the owner want to know what the annual energy costs will be like, and to be able to choose the right technical systems for the building. Failing the latter might lead to poor indoor climate. The consultants tools to simulate building energy and climate has become more and more advanced, and are able to accurately predict heat flows through building envelope. Yet still large variances in heating energy use are found in similar building when measurements are taking place, indicating that events happen that are not easily predicted. This study shows large differences in annual space heating when applying a more realistic model for window opening. The impact increases with higher indoor temperatures and better insulation levels. The chance that a consultant will underestimate the energy use is great. A model for variable set-point temperature was also tested, and was found to give lower indoor temperatures.This thesis is attached to the Research Centre on Zero Emission Building (ZEB).The vision of ZEB is to eliminate the greenhouse gas emissions caused by buildings. The Centre encompasses both residential and commercial buildings, as well as public buildings. This study focuses on residential buildings.