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The Capital of Budapest is divided into 22 districts. One of the biggest local governments is the district called Óbuda – Békásmegyer. It has 127.000 inhabitants and is the 6th biggest municipality of Hungary. The City Council of Óbuda approved a development plan for the district which focuses on the energy efficient reconstruction of the building blocks as main duty. In total there are 33,981 flats built with an industrial prefabricated concrete system. These flats are in a very bad condition concerning the windows, walls, roof insulation and the efficiency of the central heating system. Energy and cost saving are of great importance for the people living in these blocks. In 2003 –2004 Óbuda finished a big panel reconstruction programme with a subsidy of the National Government. In total about 16 panel blocks where renovated within this program, followed by a 20% municipal subsidy program for flat associations. The municipality of Óbuda decided recently to continue with the energy efficient building retrofitting programme in the next years.


Site facts and figures

  • Estimated population involved: 3,000
  • Approx. geographical area coverage: Information will follow
  • Approx. energy saving: 355 MWh/y electricity and 2,188 MWh/y heating
  • Approx. energy from RES: 726 MWh/y heating



In the framework of the CONCERTO refurbishment project in Óbuda, Budapest, the building envelope of Hungary’s largest building block “The Village” was insulated to a standard better than the national requirements for new buildings. Besides the insulation of the roof and the entire façade (10 cm Styrofoam) the refurbishment measures also comprised the replacement of 1,800 outdated windows by new 5 chamber plastic windows (which equals to more than 90 % of the building’s windows). Furthermore, the heating system infrastructure (Picture 1) was renewed.

In addition, the domestic hot water preparation in the “The Village” was separated from the conventional district heating system and connected to a new grid, supplied by solar thermal collectors with a total surface of 1,515 m² (Picture 2). Two large-scale storages (in total 100 m3) will store the heat and the district heating connection will supply peak load (Picture 3).

Simulations show that 846 MWh of the 1,632 MWh needed for domestic hot water preparation can be covered by the solar thermal system (coverage fraction of 51.6 %). Find out about additional technical data in the “more detailed” section.


The solar heating grid

In the refurbished building block in Óbuda, the domestic hot water preparation was separated from the conventional district heating system and connected to a new grid, supplied by solar thermal collectors with a total surface of 1,515 m². Two large-scale buffer-storages (in total 100 m3) and the connection to the district heating network supply the peak load (Figure 1).

The following table shows the construction components:


Table 1
Table 1


A simulation was performed, which resulted in a necessary peak power of 1,061 kW. The energy savings by the solar thermal system were predicted to account to 1,128 MWh, reducing CO2 emissions by 244 tons annually. A coverage fraction of 51.6 % for domestic hot water generation was calculated and a payback period of 3 years (including government funds) was predicted by the STACCATO team. Figure 2 and 3 show screenshots of the building service control system.

Lessons learnt

The following information has been gathered as part of the CONCERTO Premium policy research.

Benefits of CONCERTO:

Key benefits:

  • Increase in the value of the flats - about  10% above market average
  • Occupants’ quality of life improved
  • Reduction of CO2 emissions as a result of better energy efficiency and the application of renewable energy sources.
  • Energy savings and hence cost savings for inhabitants


Also, the image of the area was improved because the building looks good, therefore the flats are now easier to sell, more attractive. Before renovation measures an increase in awareness was achieved. People recognised, that it was a good thing to invest in the project and talked to neighbours, resulting in a multiplier effect. Overall, the project is considered to be a very big success, because it achieved the energy savings targets. It was a big media success – it proved that ambitious retrofitting is technically possible and that inhabitants will see savings on their bills, providing actual proof to the public that it is worth doing. The project provided therefore the foundation for a large scale national awareness campaign run by the organisation “Energia Klub”.


Barriers encountered:

Technical barriers:

After commissioning during the monitoring phase, underperformance of the building became visible: 50% of district heating should have been saved but, only 20-25% were saved, despite insulation and solar hot water installation. This was due to mistakes having been made during installation. An independent engineer was hired and mistakes were found to be incorrect connection of pipes. Also, programming for pumps and valves had to be corrected. Once rectified, a jump in energy savings was noticeable. It is now around 40-45%, if accounting for losses the Target of 50% has been achieved. Before CONCERTO there was only one central meter. As part of the project, cost-distribution meters (not heat meters) were added to 4 radiators per flat (not in bathrooms). The concierge of the building managed to negotiate an agreement to get monthly, electronic readings of cost meters, via a transmitter fitted in the lift. Monthly billing could therefore now be implemented (previously a flatrate for heating had been applied).

Economic barriers: The Obuda-project had fallen behind, as it was difficult to find an appropriate financing scheme, as there were restrictions on who can accept a

CONCERTO-grant. In the end there was a combination of funding from the municipality, the state and CONCERTO, but harmonising these has not been easy. The company that installed the solar system went bankrupt.

Social barriers:

There was huge media interest – everyone wanted to know how much could be saved as soon as the building was refurbished, but the monitoring period had to be completed first, so there was a conflict of interest between the dissemination team and technical monitoring team, as well as a general timing issue. The local energy advice centre wasn’t a big success – people did not come for energy advice but to complain about building works (problems with windows etc.).  If the centre had been open every day, instead of only 1 day a week it may have been more successful. Another issue was that due to the financial crisis a lot of skilled craftmen went to Germany resulting in a skills drain from Hungary. Success factors identified:

Technical success Factors:

Technical solutions were found that allowed people to continue living in their flats during the refurbishment. Only limited access to flats by builders was needed.

Social success factors:

Information campaign for the households didn’t stop after a positive decision was reached at the general assembly. Those living there were not being moved during the works, hence keeping them informed was an integral part of the process – this is not only because there was the EU funding to do so. It was felt that since the householders also cover a part of the costs, they are entitled to know where their money is going. The Energia Klub staff published a bi-monthly newsletter and have created a webpage in order that others can also follow and benefit from the progress of the so-called “Village House”. The involvement of the CEU (Central European University) is allowing economic, quality and social questions to surface ( Choosing a very large landmark building (900 dwelling units), at a prominent location (near a main road, near some roman excavations, near a tramline) gave a high profile to the retrofitting agenda – everyone knows the building. The building became an icon. Having the funding in place, which constituted a large proportion of over-all cost, made it easy to convince owners - 75% voted in favour. An energy performance certificate was done for the whole building and printed in poster size. It was displayed for the public in one of the windows of the building.

Institutional success factors:

The municipality was absolutely determined to make this project happen as a demonstration project. Senior politicians were involved.

Economic success factors:

Owner-occupiers could obtain a large amount of funding and were happy to receive it - national funding from the panel-building retrofitting scheme and local funding were combined with EU-funding - altogether only a small percentage had to be met by owner occupiers. The Obuda project received a very large proportion of the annual allocation for the panel-block support scheme (meaning that other projects lost out), but this was crucial to the success of this important demonstration project. The prospect of receiving EU-funding was an important driver for the project.

Other success factors:  political success – the fact that the project succeeded and broadly reached its targets allowed politicians to benefit from it.


Business models used:

No particular business model was used. Besides the European Union, the Hungarian government also offers direct support for the renovation of such ’panel blocks’ through the ’Panel Plus’ funding scheme, in the framework of which those improvements are supported which lead to household energy-savings, the improvement and modernisation of mechanical equipment, as well as the installation of systems that increase the use of renewable energy in industrially constructed buildings. This scheme had decreasing funds every year and now has been phased out! Household did have to contribute a small percentage to the overall cost, but were able to receive a subsidized loan for this. The monthly repayments are affordable - about (5000 forints, around 20 Euros).


Legacy – follow-on projects:

There is the grants scheme open for all these panel blocks and it is believed that having the prominent demonstration project in Obuda kick-started other refurbishment activities. Often the refurbishments are not as complex as the one in Obuda, sometimes only tackling wall insulation, rarely extending to solar installations. Before the Obuda-project many doubted the benefits of energy efficiency retrofitting, but now they can see proof of the benefits, especially that energy bills are lower.


Legacy - Policy Developments:

“Energia klub” reportet on projects, got information into newspapers, got to decision makers, influenced policy changes. The Obuda-project is a success for the municipality, politicians can use it well for the next election, there is an office to help the other blocks to do further improvements. It is believed that they give some grants to other blocks.

The CONCERTO approach

Five apartment buildings – nearly 900 flats – are being given a complete insulation makeover, the roofs and the entire facades will be isolated. Windows will be replaced throughout and the heating systems will be renewed. The overall objective is an insulation standard that goes far beyond the requirements stipulated in Hungarian law.

An enormous impact on non-insulated buildings is expected.


The participation of the municipalities together with the private house owners is unique in this project. They will work together to make use of the large energy saving potentials and to introduce sustainable energy in the energy supply of the area.


Péter Puskás

Building aspects

  • Installed Renewable Energy Sources
  • solar thermal collectors

Thematic Field

  • Refurbished Building(s)
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Project data