The first pie chart presents the percentages of energy use in an average Australian household. The second pie chart illustrates how greenhouses are emitted, which is determined by the energy used.
Overall, heating contributed to the highest energy use and water heating was the most significant contributor to greenhouse emissions, whereas cooling accounts for the smallest share of both energy consumption and emissions.
Heating and water heating together contribute the majority of energy use, with heating at 42% and water heating at 30%. However, their contribution to greenhouse gas emissions is markedly different: heating accounts for only 15% of emissions, while water heating is responsible for 32%, the highest of all categories. This indicates that while heating requires more energy, it is relatively produced less emissions compared to water heating.
In contrast, categories such as refrigeration, other appliances, and lighting show a different pattern. These three account for 7%, 15%, and 4% of energy use respectively, but their share of greenhouse gas emissions are substantially higher: 14%, 28%, and 8%. Thus, these categories produce approximately twice the emissions to their energy consumption, highlighting their lower efficiency in terms of emissions per unit of energy.