Zhengen Ren

A model for predicting household end-use energy consumption and greenhouse gas emissions in Australia

A new tool for predicting the total energy consumption and associated greenhouse gas (GHG) emissions of Australian households is developed by integrating the thermal efficiency of the building envelope, installed equipment and appliances, and different occupancy profiles with energy end-use modules for space heating, space cooling, water heating, lighting, and plug-in appliances. Space heating and cooling energy consumption are simulated by an enhanced version of a house energy rating tool - AccuRate, modified to account for specific heating, ventilation and air-conditioning (HVAC) system efficiency and occupancy profile. Individual modules for hot water, lighting and appliances are developed, calibrated and assessed against available published end-use data in Australia and New Zealand. The tools integrated capability to predict the annual energy consumption of a tenant-occupied house in Melbourne is validated with actual data measured over a 12-month period.

Assessment of Urban Heat Island and Mitigation by Urban Green Coverage

Urban heat island (UHI) is a growing threat to human well-being and poses increasing pressure on urban utility infrastructure, especially during summer months. This study examined the UHI in Melbourne using remote sensing imagery from MODIS to derive land surface temperature (LST) for the summer of 2009. Then, the potential of urban green coverage in reducing extreme summer temperatures in Melbourne was investigated using an urban climate model for 2009 and for projected 2050 and 2090 future climates. Modeling results showed that the average summer daily maximum (ASDM) temperature differences between Melbourne CBD, suburbs and rural areas were in the range of 0.5–2.0 °C. It was also found that despite the projected climate warming in 2050 and 2090, the cooling benefit in terms of the reduction in the average summer daily maximum temperature due to various urban forms and vegetation schemes remains similar to that estimated for 2009. Thus, the cooling benefit due to various urban forms and green schemes in future climates can be reasonably projected based on the benefits identified with the present-day climate.

Modeling the Impacts of Disruptive Technologies and Pricing on Electricity Consumption

This chapter examines scenarios for rapid uptake of new distributed energy resources and energy storage, and explores a hypothesis that adoption of residential “network tariffs” will reduce the distortional effects of volume-based tariffs on residential energy consumption patterns. The modeling methodology examines annual electricity consumption for specific dwelling types in Townsville in Northern Queensland, Australia, using network-based tariffs, feed-in-tariffs and time-of-use rates for solar photovoltaic generation, and battery storage. The analysis demonstrates that electricity consumption could drop by more than 10% in the next decade. The scenario results demonstrate that cost-reflective tariffs can improve network utilization, and potentially put downward pressure on retail prices.

Climate Change Impacts on Housing Energy Consumption and its Adaptation Pathways

Australian household energy consumption contributes about 13 % to the total national greenhouse gas (GHG) emissions, and thus, to climate change. At the same time, climate change will in turn impact the total energy consumption and GHG emissions from the residential sector. This study investigated the potential impact of climate change on the total energy consumption and related GHG emissions of housing in Brisbane, Australia (a heating and cooling balanced climate region) and identified potential pathways for existing and new residential buildings to adapt to climate change by simulations in terms of the resilience to maintain the level same as or less than the current level of total energy consumption and GHG emissions.