The near-optimal feasible space of a renewable power system model

• Published in: Electric power systems research Vol. 190; p. 106690
• Main Authors: Neumann, Fabian, Brown, Tom
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.01.2021; Elsevier Science Ltd
• Subjects: Alternative energy; Electric power systems; Electricity distribution; Electricity generation; Hydrogen storage; modeling to generate alternatives; Optimization; Power flow; power system economics; power system modeling; sensitivity analysis; Structural models; Wind power; modeling to generate alternatives; optimization; sensitivity analysis; power system modeling; power system economics
• ISSN: 0378-7796; 1873-2046
• DOI: 10.1016/j.epsr.2020.106690

•A single least-cost solution underplays the degree of freedom in long-term planning.•Systematically explores decision space of generation, storage and grid expansion model.•Study the European power system for CO2 reduction targets between 80% and 100%.•Near the optimum, many similarly costly but technologically diverse solutions exist.•New transmission lines and hydrogen storage appear essential for low-cost solutions. Models for long-term investment planning of the power system typically return a single optimal solution per set of cost assumptions. However, typically there are many near-optimal alternatives that stand out due to other attractive properties like social acceptance. Understanding features that persist across many cost-efficient alternatives enhances policy advice and acknowledges structural model uncertainties. We apply the modeling-to-generate-alternatives (MGA) methodology to systematically explore the near-optimal feasible space of a completely renewable European electricity system model. While accounting for complex spatio-temporal patterns, we allow simultaneous capacity expansion of generation, storage and transmission infrastructure subject to linearized multi-period optimal power flow. Many similarly costly, but technologically diverse solutions exist. Already a cost deviation of 0.5% offers a large range of possible investments. However, either offshore or onshore wind energy along with some hydrogen storage and transmission network reinforcement appear essential to keep costs within 10% of the optimum.