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The optimal is not always the best: Life cycle impacts of near-optimal energy systems

Author

Listed:
  • de Tomás-Pascual, Alexander
  • Pérez-Sánchez, Laura À.
  • Sierra-Montoya, Miquel
  • Lombardi, Francesco
  • Pfenninger-Lee, Stefan
  • Campos, Inês
  • Madrid-López, Cristina

Abstract

Energy system optimization models (ESOMs) can be used to guide long-term energy transitions but often overlook environmental impacts and the diversity of solutions close to the cost-optimal one. Here, we combine an ESOM using Modelling to Generate Alternatives (MGA) with Life Cycle Assessment (LCA) to evaluate 260 near-optimal and technologically diverse carbon-neutral energy system designs for Portugal in 2050 across five environmental indicators: climate change, land use, water use, ecotoxicity, and materials. Using the Calliope energy modelling framework and ENBIOS for environmental assessment, we find that system designs whose cost is within 10 % of the minimum feasible cost provide up to 50 % lower environmental impacts. Our results reveal a trade-off between technological diversity and environmental performance, showing that while diversity enhances resilience, this may come with a significant increase in environmental drawbacks. Solar photovoltaic and battery technologies dominate the environmental impacts, particularly in water consumption and critical material use. This study shows that traditional cost-optimal energy system designs may not be environmentally optimal. Exploring near-optimal alternatives reveals lower-impact solutions and supports more inclusive planning for energy transitions.

Suggested Citation

  • de Tomás-Pascual, Alexander & Pérez-Sánchez, Laura À. & Sierra-Montoya, Miquel & Lombardi, Francesco & Pfenninger-Lee, Stefan & Campos, Inês & Madrid-López, Cristina, 2025. "The optimal is not always the best: Life cycle impacts of near-optimal energy systems," Applied Energy, Elsevier, vol. 399(C).
    • Handle: RePEc:eee:appene:v:399:y:2025:i:c:s0306261925012176
    DOI: 10.1016/j.apenergy.2025.126487
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    1. DeCarolis, Joseph F., 2011. "Using modeling to generate alternatives (MGA) to expand our thinking on energy futures," Energy Economics, Elsevier, vol. 33(2), pages 145-152, March.
    2. Claudia R. Binder & Susan Mühlemeier & Romano Wyss, 2017. "An Indicator-Based Approach for Analyzing the Resilience of Transitions for Energy Regions. Part I: Theoretical and Conceptual Considerations," Energies, MDPI, vol. 10(1), pages 1-18, January.
    3. Marta Victoria & Kun Zhu & Tom Brown & Gorm B. Andresen & Martin Greiner, 2020. "Early decarbonisation of the European energy system pays off," Nature Communications, Nature, vol. 11(1), pages 1-9, December.
    4. Francesco Lombardi & Stefan Pfenninger, 2025. "Human-in-the-loop MGA to generate energy system design options matching stakeholder needs," PLOS Climate, Public Library of Science, vol. 4(2), pages 1-19, February.
    5. Lombardi, Francesco & Pickering, Bryn & Pfenninger, Stefan, 2023. "What is redundant and what is not? Computational trade-offs in modelling to generate alternatives for energy infrastructure deployment," Applied Energy, Elsevier, vol. 339(C).
    6. Kharrazi, Ali & Sato, Masahiro & Yarime, Masaru & Nakayama, Hirofumi & Yu, Yadong & Kraines, Steven, 2015. "Examining the resilience of national energy systems: Measurements of diversity in production-based and consumption-based electricity in the globalization of trade networks," Energy Policy, Elsevier, vol. 87(C), pages 455-464.
    7. Xexakis, Georgios & Hansmann, Ralph & Volken, Sandra P. & Trutnevyte, Evelina, 2020. "Models on the wrong track: Model-based electricity supply scenarios in Switzerland are not aligned with the perspectives of energy experts and the public," Renewable and Sustainable Energy Reviews, Elsevier, vol. 134(C).
    8. Price, James & Keppo, Ilkka, 2017. "Modelling to generate alternatives: A technique to explore uncertainty in energy-environment-economy models," Applied Energy, Elsevier, vol. 195(C), pages 356-369.
    9. Esser, Katharina & Finke, Jonas & Bertsch, Valentin & Löschel, Andreas, 2025. "Participatory modelling to generate alternatives to support decision-makers with near-optimal decarbonisation options," Applied Energy, Elsevier, vol. 395(C).
    10. Jan-Philipp Sasse & Evelina Trutnevyte, 2020. "Regional impacts of electricity system transition in Central Europe until 2035," Nature Communications, Nature, vol. 11(1), pages 1-14, December.
    11. Trutnevyte, Evelina, 2016. "Does cost optimization approximate the real-world energy transition?," Energy, Elsevier, vol. 106(C), pages 182-193.
    12. Aditya Sinha & Aranya Venkatesh & Katherine Jordan & Cameron Wade & Hadi Eshraghi & Anderson R. Queiroz & Paulina Jaramillo & Jeremiah X. Johnson, 2024. "Diverse decarbonization pathways under near cost-optimal futures," Nature Communications, Nature, vol. 15(1), pages 1-15, December.
    13. Li, Francis G.N. & Trutnevyte, Evelina, 2017. "Investment appraisal of cost-optimal and near-optimal pathways for the UK electricity sector transition to 2050," Applied Energy, Elsevier, vol. 189(C), pages 89-109.
    14. Michaja Pehl & Anders Arvesen & Florian Humpenöder & Alexander Popp & Edgar G. Hertwich & Gunnar Luderer, 2017. "Understanding future emissions from low-carbon power systems by integration of life-cycle assessment and integrated energy modelling," Nature Energy, Nature, vol. 2(12), pages 939-945, December.
    15. Tobias Junne & Sonja Simon & Jens Buchgeister & Maximilian Saiger & Manuel Baumann & Martina Haase & Christina Wulf & Tobias Naegler, 2020. "Environmental Sustainability Assessment of Multi-Sectoral Energy Transformation Pathways: Methodological Approach and Case Study for Germany," Sustainability, MDPI, vol. 12(19), pages 1-28, October.
    16. Wang, Yong & Li, Lin, 2013. "Time-of-use based electricity demand response for sustainable manufacturing systems," Energy, Elsevier, vol. 63(C), pages 233-244.
    17. Sasse, Jan-Philipp & Trutnevyte, Evelina, 2023. "Cost-effective options and regional interdependencies of reaching a low-carbon European electricity system in 2035," Energy, Elsevier, vol. 282(C).
    18. Jan-Philipp Sasse & Evelina Trutnevyte, 2023. "A low-carbon electricity sector in Europe risks sustaining regional inequalities in benefits and vulnerabilities," Nature Communications, Nature, vol. 14(1), pages 1-15, December.
    19. Pedersen, Tim T. & Victoria, Marta & Rasmussen, Morten G. & Andresen, Gorm B., 2021. "Modeling all alternative solutions for highly renewable energy systems," Energy, Elsevier, vol. 234(C).
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