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Meta-analysis on necessary investment shifts to reach net zero pathways in Europe


Reaching a pathway towards net zero GHG emissions requires rapid and massive investments in low-carbon infrastructure. To redirect finance flows accordingly, particularly the European Union places an emphasis on sustainable finance regulation. However, the specific investment shifts required are not fully understood, which could lead to an insufficient steering effect for crucial technologies. Here we conduct a meta-analysis to derive the required technology-level investment shifts for climate-relevant infrastructure until 2035. We find a steep uptick in overall investment need, with almost €90 billion yr−1 being required already within the very near term (2021–25). Investment shifts are most drastic for power plants, electricity grids and rail infrastructure, which is even increased by the ambitions to become independent from Russian gas imports. Our findings highlight the need for sustainable finance policies that take into account the financing structures of these sectors specifically.

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Fig. 1: Past investments and future investment needs in Europe.
Fig. 2: Investment shifts required between 2016–20 and 2021–25.
Fig. 3: All data points derived in the meta-analysis.
Fig. 4: Spread of the investment needs.
Fig. 5: Investment needs by type of institutions for five key technologies.
Fig. 6: Increase in investment needs for a reduction of imports of Russian gas.

Data availability

All data generated or analysed during this study are included in the article and its Supplementary Information and Data files. Source data are provided with this paper.

Code availability

The code necessary to reproduce the six main figures and the t-test presented in the Supplementary Information is available at Zenodo65 under the identifier


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L.K. and B.S. have received funding from the EU Horizon 2020 research and innovation programme, European Research Council (grant agreement no. 948220, project no. GREENFIN) for this project. The compilation of the database and the plotting of the results were supported by F. Hafner, N. Knecht, G. Mancini and M. Prébandier.

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Authors and Affiliations



B.S. and L.K. developed the research idea. L.K. compiled and analysed the data. L.K. and B.S. interpreted the results and wrote the paper. B.S. secured project funding.

Corresponding authors

Correspondence to Lena Klaaßen or Bjarne Steffen.

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The authors declare no competing interests.

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Nature Climate Change thanks Johannes Schmidt, Kyle Herman and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Text, Figs. 1–12, Tables 1–10 and refs. 1–71.

Supplementary Data 1

Literature overview; Data analysis; Extended analysis—Russian gas phase out.

Supplementary Data 2

PRISMA checklist.

Source data

Source Data Fig. 1

Statistical source data.

Source Data Fig. 2

Statistical source data.

Source Data Fig. 3

Statistical source data.

Source Data Fig. 4

Statistical source data.

Source Data Fig. 5

Statistical source data.

Source Data Fig. 6

Statistical source data.

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Klaaßen, L., Steffen, B. Meta-analysis on necessary investment shifts to reach net zero pathways in Europe. Nat. Clim. Chang. 13, 58–66 (2023).

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