Vintage-Based Formulations in Multi-Year Investment Modelling for Energy Systems

TL;DR

The paper addresses multi-year investment modeling in energy systems and compares simple, vintage, and compact formulations. It proposes a compact formulation that retains year-specific availability while reducing dimensionality, implemented in TulipaEnergyModel.jl. The authors discuss implications of omitting vintage from production variables and detail trade-offs between fidelity and tractability. The work enables scalable long-term planning for renewable-dominated energy systems with manageable computational requirements.

Abstract

This paper reviews two established formulations for modelling multi-year energy investments: the simple method, which aggregates all capacity regardless of commissioning year, and the vintage method, which explicitly tracks investments by year to capture differences in technical parameters over time. While the vintage method improves modelling fidelity, it significantly increases model size. To address this, we propose a novel compact formulation that maintains the ability to represent year-specific characteristics while reducing the dimensionality of the model. The proposed compact formulation is implemented in the open-source model TulipaEnergyModel.jl and offers a tractable alternative for detailed long-term energy system planning.