The development of the electricity supply sector is characterised by a dynamically growing renewable energy market and an increasing share of renewable electricity. This will compensate for the phasing out of nuclear energy and reduce the number of fossil fuel-fired power plants required for grid stabilisation. By 2050, 79% (in the Energy [R]evolution scenario) resp. 95% (in the advanced Energy [R]evolution scenario) of the electricity produced worldwide will come from renewable energy sources. ‘New’ renewables – mainly wind, solar thermal energy and PV – will contribute over 60% of electricity generation under the advanced Energy [R]evolution scenario and 79% in the basic version. The following strategy paves the way for a future renewable energy supply:
- The phasing out of nuclear energy and rising electricity demand will be met initially by bringing into operation new highly efficient gas-fired combined cycle power plants, plus an increasing capacity of wind turbines, biomass, concentrating solar power plants and solar photovoltaics. In the long term, wind will be the most important single source of electricity generation. In order to achieve the projections under the advanced Energy [R]evolution scenario, the lifetime of new coal power stations installed between 2007 and 2015 has been reduced from 40 to 20 years. This is especially important in China, where over 200,000 MW of new coal power plants have been built between 2002 and 2010. A 40 year lifetime would have led to an excessively large share of coal in the global power generation. Possible stranded investments could be addressed politically, for example through money from emissions trading or other climate and energy programmes.
- Solar energy, hydro and biomass will make substantial contributions to electricity generation. In particular, as non-fluctuating renewable energy sources, hydro and solar thermal, combined with efficient heat storage, are important elements in the overall generation mix. The advanced scenario can be achieved if annual growth rates in the renewables sector remain in the same range as over the past decade (25 – 35% annually) for the next 15 to 20 years. Both the wind and solar industries are confident that this is technically and economically possible, if the necessary political support is provided.
- The installed capacity of renewable energy technologies will grow from the current 1,080 GW to 9,585 GW in 2050. Increasing renewable capacity by a factor of nine within the next 40 years requires political support and well-designed policy instruments, however. There will be a considerable demand for investment in new production capacity over the next 20 years. As investment cycles in the power sector are long, decisions on restructuring the world’s energy supply system need to be taken now.
- In the advanced Energy [R]evolution scenario, the total renewable installed capacity will grow to 3,359 GW by 2020 and 13,229 GW by 2050. A significant share of the fluctuating power generation will be used to supply electricity to vehicle batteries and to produce hydrogen as secondary fuel in transport and industry. By using load management strategies, both energy demands will reduce excess electricity generation and provide balancing power and energy to the energy systems.
To achieve an economically attractive growth in renewable energy sources, a balanced and timely mobilisation of all technologies is of great importance. This mobilisation depends on technical potentials, cost reduction and technological maturity. Figure 6.6 shows the comparative evolution of the different renewable technologies over time. Up to 2020, hydro power and wind will remain the main contributors to the growing market share. After 2020, the continuing growth of wind will be complemented by electricity from biomass, photovoltaic and solar thermal (CSP) energy. For the advanced Energy [R]evolution scenario it is vital to implement infrastructure improvements such as smart grids, greater interconnection between these grids and large scale offshore wind networks as well as increased R&D for storage technologies. All these changes need to happen about ten years in advance of the basic Energy [R]evolution version.