Values are expressed in Billions USD 2015. The charts show multi-model means and ranges. In the first chart, total investments in the global energy system are shown excluding fuel and operations and maintenance costs. In 2000, the total is our own estimates based on the number reported in the World Energy Outlook plus the investments in energy efficiency. The value ‘2016>2030’ is the future average annual energy investment between 2016 and 2030 estimated from the models.
Chart 2 presents the minimum, the mean, the maximum of the average annual energy investment per regions, per categories (see details hereafter) and per climate mitigation scenarios, estimated by the models over the period 2016-2050. Supply and Demand side investments are accounted in the total. The region definition follows the regional aggregation used in the SSP database (
more details in this page). Europe is the EU-28.
Chart 3 presents the projected global average annual fossil fuel supply investments and the relative changes to ‘current policies’ by category from 2016 to 2030. Values are calculated by cumulating the models’ undiscounted investment estimates and averaging them over the full 2016-2030 period. Values represent multi-model means. The empty square provides a visual reference for the NDC scenario.
Chart 4 shows the projected global average annual low-carbon energy supply-side investments as a share of total supply-side investments. Solid lines represent multi-model means. Estimates shown here include supply-side investments in renewable electricity and hydrogen production, bioenergy extraction and conversion, uranium mining and nuclear power, fossil energy equipped with CCS, and the portion of electricity T&D and storage investments that can be attributed to low-carbon electricity generation.
The investment categories have been harmonized across charts. Electricity represents the investment in the power sector. Subcategory Electricity/Fossil Fuels does include CCS technologies. Subcategory Electricity/Grid accounts for investments in the power grid and storage. Subcategory Electricity/Renewables does not account for biomass powered plants.The categories Fuels account for the extraction and the conversion of the fuel. Subcategory Fuel/Hydrogen accounts for the production of hydrogen from fossil fuel or non-fossil fuels.
The six global energy-economy models, or integrated assessment (IAM) frameworks, drawn upon in this study include
AIM/CGE,
IMAGE,
MESSAGEix-GLOBIOM,
POLES,
REMIND-MAgPIE, and
WITCH-GLOBIOM. These models span a range from least-cost optimization to computable general equilibrium models and from game-theoretic to recursive-dynamic simulation models. Such diversity is beneficial for shedding light on those model findings which are robust to diverging assumptions and on potential outliers deserving of further investigation. Of particular importance for the current study, the six models have broad coverage of different types of energy technologies across the entirety of the global energy system, including resource extraction, power generation, fuel conversion, pipelines/transmission, energy storage, and end-use/demand devices, and are therefore well-positioned to assess the evolving nature of the energy and climate mitigation investment portfolio over time.
Four scenarios are explored in the work. ‘Current Policies’ serves as each model’s reference case (or baseline). The scenario takes into account those energy- and climate-related policies that were already “on the books” of countries as of 2015; in other words, it reflects the early bridges to the low-carbon economy that policy makers have already implemented in various parts of the world. In addition to the reference case, the modelling teams each ran three scenarios where policies for low-carbon energy, energy efficiency, and climate change mitigation are tightened: ‘Nationally Determined Contributions’ (‘NDC’), ‘Well Below 2 Degrees’ (‘2C’), and ‘Toward 1.5 Degrees’ (‘1.5C’). Population and socio-economic development assumptions across all scenarios are in line with the ‘middle-of-the-road’ storyline of the Shared Socioeconomic Pathways (SSP2).