EVALUATION OF RENEWABLE ENERGY MODELLING METHODOLOGIES WITHIN DOMESTIC BUILDING DESIGN COMPLIANCE PROCEDURES

摘要

In response to the ratification of the Kyoto Protocol, the European Union has the target of reducing CO_2 emissions by 20% from 1990 levels by 2012. As part of this obligation, the UK is aiming to reduce its own CO_2 emissions by 34% based on 1990 levels by 2022 (DECC). In order to assess emission reduction compliance from domestic housing, the UK Government have developed a Standard Assessment Procedure for new and existing dwellings, called SAP 2009 (DECC 2010). This document contains key energy performance indicators including energy consumption per unit floor area, energy cost rating (SAP rating), environmental impact rating based on CO_2 emissions (EI rating) and dwelling CO_2 emission rate (DER). This work involves an analysis of the methodologies by which PV and solar thermal technologies are assessed to contribute to energy generation and carbon reduction projections for domestic dwellings. Using comparative analysis with advanced software simulations along with measured data from field installations, the evaluation is focussed upon the projected energy contributions and CO_2 emission reductions arising from these technologies in the context of dwellings' overall design targets. Specifically, methods used by SAP to estimate solar irradiation are evaluated with potential limitations quantified and described, and comparisons to simulations made using PV-GIS and meteorological data for three locations in the south, midlands and north of England respectively. The annual solar energy available to a solar thermal system predicted by SAP is compared with modelled and measured data for Camborne, Nottingham and Durham. The impact of DHW demand and occupancy of a household on solar input and fuel savings made is then investigated using measured data from (Forward & Roberts 2008) and SAP predicted values.