Creation of an improved residential space heating calculation model for the Irish energy performance assessment tool

Panel: 5. Energy use in buildings: projects, technologies and innovation

This is a peer-reviewed paper.

Authors:
Geoff Hunter, Centre for Rural and Sustainable Development, Limerick Institute of Technology (Tipperary), Ireland
Seamus Hoyne, Limerick Institute of Technology, Ireland
Liam Noonan, Limerick Institute of Technology, Ireland

Abstract

This paper outlines an ongoing study into the energy performance gap (EPG) in domestic dwellings, using real-time wireless sensor data relating to the energy consumption of 95 retrofitted households, situated in rural and town settings in Ireland. The database of room temperatures and electrical energy to the main heating device, enabled the verification of actual, measured heating patterns and corresponding room temperatures, allowing direct comparison to the normative model, the Dwelling Energy Assessment Procedure (DEAP), which is currently used to calculate the energy performance rating of dwellings. The EPG is defined here, as the percentage by which the measured energy consumption of dwellings is above, or below the normative, calculated value. The literature review on the EPG around Europe found that, on average, the measured energy consumption in homes can be 25% below the calculated consumption and narrowing the EPG would facilitate more accurate energy savings projections for policy planners, energy managers and home owners looking to invest in cost optimal thermal retrofits to reduce both carbon emissions and outlay on energy. This paper describes the extraction and formulation of the relevant sensor data and proceeds to analyse the heating schedules and rest-of-home room temperatures in an effort to strengthen the DEAP model by focussing on the space heating aspect alone, which is shown to be the largest cause of the gap. The results will be statistically verified and directly compared to the current assumptions on the heating schedule and set point room temperatures in DEAP. Sensor-derived information on secondary heating will also be available. DEAP assumes that primary heating systems are used for 56 hours per week during the heating season with 10% of the space heating coming from secondary sources along with a maintained internal rest-of-home temperature of 18°C during heating periods. The research expects to prove that the actual, measured values will differ significantly from these assumptions. This paper presents the mid-term research findings which will conclude in January 2016.