Combining the projections on population development, GDP growth andenergy intensity results in future development pathways for SouthAfrica’s energy demand. These are shown in Figure 6.3 for both the Reference and the Energy Revolution scenarios. Under the Reference scenario, total primary energy demand will increase by a factor of 1.6from the current 5,496 PJ/a to 8,868 PJ/a in 2050. In the Energy[R]evolution scenario, primary energy demand increases up to 6,361PJ/a by 2020 and decreases to a level of 5,381 PJ/a in 2050.The accelerated increase of energy efficiency, which is a crucial prerequisite for achieving a sufficiently large share of renewable energy sources for our energy supply, is beneficial not only for the environment, but also from an economic point of view. Taking into account the full service life,in most cases the implementation of energy efficiency measures saves costs compared to the additional energy supply. The mobilisation of cost-effective energy saving potentials leads directly to the reduction of costs. A dedicated energy efficiency strategy thus also helps to compensate in part for the additional costs required during the market introduction phase of renewable energy sources.

Under the Energy Revolution scenario, electricity demand is expected to decrease disproportionately, with households and services the mainsource of reduced consumption. With the exploitation of efficiency measures, but with an increase use of electric vehicles, an increase cannot be avoided, leading to electricity demand of around 375 TWh inthe year 2050. Compared to the Reference scenario, efficiency measures avoid the generation of about 123 TWh. This reduction in energy demand can be achieved in particular by introducing highlyefficient electronic devices using the best available technology in alldemand sectors. Employment of solar architecture in both residential and commercial buildings will help to curb the growing demand foractive air-conditioning. Efficiency gains in the heat supply sector are even larger. However under the Energy Revolution scenario, final demand for heat supply will increase by 38% until 2050 (see Figure6.5). Compared to the Reference scenario, consumption equivalent to95 PJ/a is avoided through efficiency gains by 2050. As a result ofenergy-related renovation of the existing stock of residential buildings, as well as the introduction of low energy standards and ‘passivehouses’ for new buildings, enjoyment of the same comfort and energy services will be accompanied by a much lower future energy demand. In the transport sector, it is assumed under the Energy Revolution scenario that energy demand will remain roughly on today’s level of663 PJ/a by 2050, while under the Reference scenario transport energy needs doubles. This can be achieved by the introduction of highly efficient vehicles, by shifting the transport of goods from road to rail and by changes in mobility-related behaviour patterns.