Work

Impact of electricity price input methods on economic optimisation models: A case study of district heating thermal energy storage in Finland

Year: 2026

Type: article

Abstract: Various methods are used to incorporate electricity price data into optimisation models for techno-economic assessments of energy systems. While many studies rely on time-series electricity prices, they often optimise the system over an entire year to reduce computational complexity — an assumption that may not reflect practical decision-making conditions. This study evaluates the validity of that assumption by comparing three modelling approaches: the Basic model, which uses a full-year electricity price dataset; the Dynamic model, which operates with a 36-hour rolling window of known prices; and the Adaptive model, which augments the rolling window with a 12-hour AI-based forecast. The case study examines a hot water tank integrated into a Finnish district heating system, tested across storage capacities from 100 to 20,000 m 3 and multiple heat demand scenarios. Results indicate that compared to the Basic model, the Dynamic and Adaptive models estimate lower annual profits. At optimal storage sizes, profit deviations remain below 4% for the Adaptive model and under 7% for the Dynamic model. However, for large storage volumes and low demand, deviations increase to 40% and 70%, respectively. The gap between the Adaptive and Dynamic models also grows with storage size, reaching up to 17%. Rolling-window models require significantly more computation time - approximately 14 and 25 times longer than the Basic model. These findings emphasise the importance of choosing a modelling approach aligned with study goals. Simplified models suit early-stage assessments, whereas for more serious evaluations, the implementation of rolling-window approaches is advised, given the volatility of current electricity markets.

Source: Applied Energy

DOI: 10.1016/j.apenergy.2026.127554

Authors: Ilia Skorniakov, Behnam Talebjedi, Timo Laukkanen, Sanna Syri

Institution: Aalto University

Language: English

Topic: Integrated Energy Systems Optimization

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Affordable and clean energy, Climate action, Industry, innovation and infrastructure

Open Access status: hybrid

Estimated APC paid: $4,430