Several organisations and companies have developed scenarios to explore global future energy pathways that achieve the Paris climate goal. This study compares 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, with a focus on main transition indicators.
Large differences in timing between scenarios
The 2 °C scenarios analysed strongly differ, with respect to the timing of emission reductions. Those by IRENA and IEA are characterised by immediate, rapid CO2 reductions mainly achieved through large energy efficiency improvements and strong scaling up of renewable energy. These scenarios avoid being strongly dependent on technologies that lead to net removal of CO2 from the atmosphere. The scenarios by Shell and WEC show more gradual emission reductions, relying heavily on CO2 removal in the second half of the century to compensate for the excess in emissions. All of the scenarios, however, agree on a rapid phaseout of the use of coal, a strong increase in renewable energy, and a fast electrification of the economy.
Use of biomass combined with carbon capture and storage
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, but require more immediate action with the risk of higher short-term costs — although scenarios with delayed action (i.e. with 2030 emission levels consistent with current pledges as indicated in countries’ Nationally Determined Contributions) show higher costs in the longer term.