The Potential for Solar Energy Use in a New Zealand Residential Neighbourhood: A Case Study Considering the Effect on CO2 Emissions and the Possible Benefits of Changing Roof Form

Abstract

Solar energy, a renewable resource, is constantly replenished by natural processes and can be used by humans more or less indefinitely. This article quantifies the potential energy from solar hot water and photovoltaics that could be generated from the roofs of the built-up areas of an existing urban neighbourhood at Glen Innes, Auckland. It examines how solar energy can contribute towards total domestic energy requirements of households for two scenarios. It also explores possibilities of enhanced potential solar contributions with changes in roof configurations. The outcomes suggest that, with minimal changes in roof configuration, the residential rooftop potential in terms of percentage contributions of total domestic energy demands (except space conditioning) could increase from 73 to 82.5 per cent for a maximum utilization scenario. For a more realistic situation, taking account of available sizes and dimensions of solar equipment the energy contribution could be enhanced from 46 to 69 per cent. Assuming a continuation of the current trends in grid-scale local generation technologies, building roofs with correct orientations to allow the collection of solar energy makes significant contributions to reducing CO2 emissions.