Examining future mitigation pathways for residential building sector heating and cooling demand

Abstract

The building sector consumes more than half of electricity, almost one third of the global energy produced and is responsible for almost one third of the global energy-related CO2 emissions. The anticipated future situation is even more dire with the building demand significantly rise due to the expected population and GDP growth followed by an increase in living standard (especially in developing countries). One way to reduce the energy demand (and thus the emissions) with no expense in comfort, is through improved thermal insulation in the buildings’ shell. Hitherto the efforts towards an energy-efficient building stock cannot offset the increase in energy demand, so additional development should be driven via technological improvements, regulations and policy initiatives.

In this thesis we developed a stylized bottom up system dynamic global model is developed as part of IMAGE (an Integrated Assessment Model). The model simulates decisions on insulation investments and the resultant building stock quality (indicated via the useful energy intensity of buildings). Furthermore, we examine the effect of insulation on the residential energy use for heating and cooling and the associated CO2 until 2100 and under different socio-economic developments. Finally, we investigate climate policies in the form of subsidies, energy standards and a carbon tax are applied to the model and their efficient on reducing the projected demands and emissions as well as their associated costs (under each above-mentioned future development).

Analysing the results, we found that effect of policies differs across the geographical regions, and under the various examined socio-economic pathways. In general, the carbon tax can successfully reduce the CO2 emissions, but not the heating demand of the residential buildings (which is some occasions increases). Contrary, higher demand (and sometimes cooling) reduction can be achieved by the other two measures, depending on the characteristics of each scenario, but the respective emission reduction achieved is insignificant. The reason is a rebound effect, which due to the reduction on the heating and cooling demands activates a fuel switching towards a less “clean” fuel mix. So, it becomes evident that for an optimum result, and to achieve the 1.5oC or 2oC target (set by the Paris Agreement) towards a decarbonized future, a mixture of policies should be utilized.