The Avedøre Green City project, located in Avedøre, Denmark, is a prime example of the significant impact that an insulation-first approach makes to energy renovation in social housing.
This project demonstrates how poor energy efficiency and outdated heating systems were transformed, yielding substantial energy savings, notable improvements to living conditions, and significant CO2 emission reductions.
The Avedøre Green City project had to overcome several challenges to perform deep renovations aiming to make heating in the housing units sustainable while keeping costs manageable and ensuring tenant cooperation.
The first challenge came as a need to establish whether buildings in Avedøre were ready for a Low Temperature District Heating(LTDH) system. This came through a preliminary evaluation of the energy performance of the housing units, which highlighted a key point.
Avedøre’s housing units were aging, their inefficiency exacerbated by poor insulation throughout the units, which not only led to high energy consumption but also increased heating costs for tenants. The challenge was how to integrate deep renovations, centred on insulation and heating upgrades, while keeping costs manageable and ensuring tenant cooperation.
Carrying out the renovation goals in the context of social housing, which houses some of the most energy-vulnerable citizens, required tenant engagement and meant that every euro spent had to be carefully planned.
The solutions explored in the Avedøre GreenCity project centred on an insulation-first approach, which laid the ground work for the shift from a 90-degree district heating system to a low temperature heating network. Renovations included upgrades to the building envelope, improved insulation of heating and hot water pipes, and the introduction of heat recovery ventilation systems.
Insulation not only played a role in improving energy efficiency but also helped future-proof the buildings by adapting them to a low-temperature district heating system, reducing energy consumption by 35% and making the units more resilient to energy price fluctuations.
The Avedøre Green City project was implemented through a combination of energy-efficient renovations and district heating upgrades. The project primarily targeted social housing units, which were previously reliant on an inefficient 90-degree district heating system.These units were retrofitted with better-insulated building envelopes and improved ventilation systems. The district heating system itself was transformed into a 65-degree low-temperature network, enhancing overall energy efficiency.
A critical aspect of the project’s success was stakeholder engagement. The Avedøre district heating company coordinated with various housing administrators, municipal representatives, and tenants to ensure smooth communication and decision-making. Tenant involvement was particularly crucial; by holding information sessions and providing clear communication through a local intranet, the project garnered support from the residents, ensuring minimal disruption during the renovation process. Moreover, the introduction of smart meters enabled tenants to monitor and control their energy use, reinforcing the long-term benefits of the insulation improvements.
Despite challenges posed by COVID-19, the project managed to meet its targets on time. The steering group, which comprised experts from various sectors, ensured that the renovations were both technically sound and socially acceptable.
The insulation-first approach implemented in Avedøre Green City led to impressive energy savings and reductions in carbon emissions. The overall energy consumption of the social housing units decreased from 27,980 MWh to 18,270 MWh, a 35% reduction in energy usage. This translated into annual savings of 9.7 GWh and a reduction of 283 tons of CO2 emissions per year once the low temperature district heating system was installed.
For residents, the benefits were immediate.The improved insulation resulted in lower heating bills and a better indoor climate, with improved air quality and thermal comfort. These upgrades also increased the value of the properties, as energy-efficient homes are increasingly attractive in the real estate market. Additionally, the project had significant economic benefits for the local community, as it created jobs in the construction and energy sectors during the renovation process.
The approach in Avedøre, particularly its insulation-first strategy, aligns with the EU’s emphasis on targeting the worst-performing buildings based on an energy efficiency first approach and decarbonising heating systems. The reductions in energy consumption (35% post-renovation) and improved building performance directly contribute to EU climate goals. By reducing household energy needs by up to 75% through insulation, Avedøre supports the broader EU effort to cut greenhouse gas emissions and foster energy resilience.
Moreover, the project illustrates the potential socio-economic benefits of the Renovation Wave. The Avedøre project’s success in creating local employment opportunities within the construction and energy sectors underscores the vital role that deep renovations can play in boosting local economies while reducing emissions.
The EU objective of decarbonising the building stock by 2050 hinges on similar projects as Avedøre being implemented at scale. Investing in insulation as the first step in renovations not only improves energy efficiency but also often paves the way to more efficient and decarbonised heating solutions, such as low-temperature district heating, making it a sustainable and affordable solution for households.
The takeaway from this project, however, is in the process. The first and foremost step was to identify how to best tackle the situation in Avedøre by giving the housing unit a comprehensive energy labelling. Armed with a better understanding of the situation, it was then decided that a Low Heat Temperature District system was the best approach.
Governments, housing authorities, and private stakeholders must focus on creating comprehensive guidelines to follow for an ideal renovation to capitalise on these benefits. By ensuring the best solutions are chosen from the start and improving the building envelope level first, stakeholders can unlock significant energy savings, reduce grid pressure, and foster the creation of more independent energy communities.
Furthermore, a secondary lesson to note is the smooth execution of the renovation, in part thanks to the consultative nature of the project. By involving citizens and the members of the community, a high level of cooperation was guaranteed.
As the EU moves toward implementing minimum energy performance standards, insulation, comprehensive guidelines and cooperation should therefore be the foundational steps in every energy renovation.
