Several organisations and companies have developed scenarios to explore global future energy pathways that achieve the Paris climate goal of limiting temperature change to well below 2 °C. A new report by PBL compares these scenarios on key transition indicators. The report shows that scenarios that delay emission reductions and phasing out fossil fuels depend on large-scale use of CO2 removal later in the century.
The report compares global 2 °C scenarios developed by Shell, BP, the International Energy Agency (IEA), the International Renewable Energy Agency (IRENA), the World Energy Council (WEC) and the European Commission (EC). It also compares these scenarios to the IPCC’s 2 °C scenarios.
Delaying climate action implies dependence on CO2 removal
The 2 °C scenarios analysed strongly differ with respect to the timing of emission reductions. Those by IRENA and the IEA show immediate, rapid CO2 reductions, with emission levels by 2030 that are about 25% below 2017 levels. These scenarios avoid being strongly dependent on technologies that lead to net removal of CO2 from the atmosphere. The scenario by Shell, on the other hand, is the only one with a CO2 emission level that is higher in 2030 than in 2017. This scenario relies heavily on CO2 removal in the second half of the century to compensate for the excess in emissions.
CO2 removal requires vast amounts of land
The two most promising options for large-scale CO2 removal from the atmosphere are bioenergy in combination with carbon capture and storage (BECCS) and reforestation. Both options require large amounts of land which may negatively affect other global sustainable development objectives, including those of food security and biodiversity protection. Scenarios with faster emission reductions in the short term minimise these risks.
Coal phased out rapidly in all scenarios
Regardless of the timing of emission reduction, all scenarios agree on a rapid phaseout of the use of coal, a strong increase in renewable energy, and a fast electrification of the economy. All scenarios, except for the scenario by Shell, show large reductions in the emissions from power generation. Scenarios that avoid a heavy reliance on CO2 removal technologies also show an absolute decline in oil use, between 2017 and 2030.
Growth in electricity largely met with renewable energy
Under all scenarios, demand for electricity will continue to grow as the share of electricity in the final energy demand increases. The growth in electricity demand will be met largely by renewable energy. Solar and wind energy, especially, demonstrate a strong growth and will become the dominant source of electricity by mid century. The increase in power generation from renewables by 2030 is the largest under the scenarios by IRENA and IEA.
The role of carbon capture
Carbon capture, utilisation and storage (CCUS) is implemented in the power sector at the remaining coal-fired power plants and old and new natural-gas-fired power plants and in reducing emissions from heavy industries that are difficult to electrify. Only the IEA and EC scenarios have low levels of CCUS implemented by 2040/2050; all the other scenarios rely on high levels of CCUS deployment. Shell’s Sky scenario, for instance, requires 10,000 large-scale CCS plants by 2070, compared to less than 50 in 2020.