Open Access

ARTICLE

Assessing the Role of Aggregated Flexibility from Public Buildings in Enhancing Renewable Energy Integration

Franjo Pranjić^1,*, Doris Beljan², Primož Praper³, Matej Fike¹, Peter Virtič¹, Antun Pfeifer², Neven Duić^2,4
1 Faculty of Energy Technology, University of Maribor, Maribor, Slovenia
2 Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Zagreb, Croatia
3 EUTRIP, Celje, Slovenia
4 School of Industrial Engineering, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
* Corresponding Author: Franjo Pranjić. Email:
(This article belongs to the Special Issue: Selected Papers from the SDEWES 2025 Conference on Sustainable Development of Energy, Water and Environment Systems)

Energy Engineering https://doi.org/10.32604/ee.2026.080284

Received 06 February 2026; Accepted 08 May 2026; Published online 15 June 2026

Abstract

This paper evaluates the role of aggregated demand-side flexibility from public buildings in supporting renewable energy integration and decarbonization of the Slovenian energy system. Using high-resolution monitoring data from over 100 public buildings and the H2RES energy system optimization model, two long-term scenarios are analyzed for the period 2020–2050: a reference scenario without public building flexibility and a flexibility scenario in which public building heat demand is electrified via heat pumps. The year 2020 is used as an internally consistent optimization reference for demand levels and technology availability, rather than as a statistical reconstruction of the observed national energy system. Reported CO₂ emissions represent modelled energy-system emissions within the covered sectors (power, heat, and industry) under exogenously imposed policy constraints and therefore may differ from national inventory totals. The results show that aggregated public building flexibility affects the temporal allocation of electricity demand and sectoral emission distribution, leading to moderate changes in renewable curtailment and heat-sector CO₂ emissions while maintaining identical renewable energy targets. The findings demonstrate that electrification and aggregation of public building demand can play a strategic role in supporting national climate objectives and system operation under high renewable penetration. It should be noted that the analyzed dataset, while based on high-resolution monitoring of more than 100 public buildings, is not statistically scaled to represent the full national building stock. The results should therefore be interpreted as indicative of system-level effects of aggregated flexibility rather than a direct national-scale quantification.

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Keywords

Demand-side flexibility; public buildings; renewable energy integration; energy system optimization; H2RES; decarbonization strategy; aggregated flexibility; energy transition

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