development of energy demand by sector
Combining the projections on population development, GDP growth and energy intensity results in future development pathways for the world’s energy demand. These are shown in Figure 6.3 for the Reference and both Energy [R]evolution scenarios. Under the Reference scenario, total primary energy demand almost doubles from 490,230 PJ/a in 2007 to 783,458 PJ/a in 2050. In the Energy [R]evolution scenario, demand increases up to 2020 by 7% but then decreases slightly below today’s level of 459,519 PJ/a by 2050. The advanced version leads to a demand of 500,762 PJ/a in 2030 and 465,995 PJ/a by 2050, similar to the basic Energy [R]evolution scenario. The accelerated increase in energy efficiency, which is a crucial prerequisite for achieving a sufficiently large share of renewable energy sources in our energy supply, is beneficial not only for the environment but also for economics. Taking into account the full lifecycle costs, in most cases the implementation of energy efficiency measures saves money compared to creating an additional energy supply. A dedicated energy efficiency strategy therefore helps to compensate in part for the additional costs required during the market introduction phase of renewable energy technologies.
Under the Energy [R]evolution scenario, electricity demand is expected to increase disproportionately, with households and services the main source of growing consumption (see Figure 6.4). With the exploitation of efficiency measures, however, an even higher increase can be avoided, leading to electricity demand of around 31,795 TWh/a in the year 2050. Compared to the Reference scenario, efficiency measures avoid the generation of about 8,549 TWh/a. This reduction in energy demand can be achieved in particular by introducing highly efficient electronic devices using the best available technology in all demand sectors. Employment of solar architecture in both residential and commercial buildings will help to curb the growing demand for active air-conditioning. Due to the increased use of electric drives instead of combustion engines in the transport sector and the bigger role of hydrogen in transport and also industry, electricity demand is significantly higher in the advanced Energy [R]evolution scenario. By 2030 the level of production reaches 30,901 TWh/a and 43,922 TWh/a by 2050, about 5.5% below the Reference scenario but 16% above the basic Energy [R]evolution version. Efficiency gains in the heat supply sector are even larger. Under the Energy [R]evolution scenario, final demand for heat supply can even be reduced (see Figure 6.5). Compared to the Reference scenario, consumption equivalent to 49,357 PJ/a is avoided through efficiency gains by 2050. As a result of energy-related renovation of the existing stock of residential buildings, as well as the introduction of low energy standards and ‘passive houses’ for new buildings, enjoyment of the same comfort and energy services will be accompanied by a much lower future energy demand. The advanced version has an even lower energy demand in the heating sector, due to the increased use of electricity, for example through geothermal heat pumps. In the transport sector, it is assumed under the Energy [R]evolution scenario that energy demand will increase by 12% to around 88,743 PJ/a in 2030 and then fall slightly afterwards to 83,507 PJ/a in 2050, saving 47% compared to the Reference scenario. This reduction 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. In the advanced version, more electric drives are used in the transport sector and hydrogen produced by electrolysis using fluctuating renewable electricity plays a much bigger role than in the basic scenario. After 2030, the final energy share of electric vehicles on the road increases to 14% and by 2050 up to 50%. More public transport systems also use electricity as well as there being a greater shift in transporting freight from road to rail.