New research from Utrecht University demonstrates that improving building envelopes is a critical first step in transitioning vulnerable neighbourhoods toward Positive Energy Districts (PEDs), particularly when combining solar photovoltaics (PV) with heat pumps.
The study finds that while increasing PV capacity can significantly enhance local renewable energy generation, PV penetration beyond 40% leads to growing mismatches between electricity supply and demand, resulting in grid stress and substantially higher neighbourhood-level battery storage requirements. By contrast, advanced building refurbishment—especially improved insulation—markedly improves system performance, reducing overall energy demand and enhancing supply–demand balance.
These insights are based on a detailed technical assessment of a social housing neighbourhood in the Netherlands, conducted within the JUST-PEPP project at Utrecht University’s Copernicus Institute of Sustainable Development. Using a building energy simulation model, the researchers modelled hourly electricity demand and supply over a typical year for all buildings in the neighbourhood. The analysis integrated solar PV, heat pumps, building envelope improvements, and neighbourhood-scale battery storage to evaluate the technical feasibility of achieving PED status.
Overall, the results underscore that renewable energy technologies alone are insufficient to enable Positive Energy Districts in vulnerable neighbourhoods. Instead, deep building renovation must precede or accompany the deployment of solar PV and heat pumps to avoid excessive storage requirements and local grid congestion.
These findings were presented by Dr. Mitali Joshi on behalf of the Utrecht University team of the JUST-PEPP project at CISBAT 2025, held from 2–5 September 2025 in Lausanne, Switzerland—a leading international conference on building performance, energy systems, and sustainability. The conference provided an opportunity for valuable exchange with international researchers and practitioners working toward climate-neutral and socially inclusive urban energy transitions.
A warm thank-you to the CISBAT organisers and the international research community for their insightful discussions and valuable feedback.
