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OVERVIEW | nZEB policies and the support tools in eCentral project target countries (Slovenia, Croatia, Hungary)

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Currently, buildings account for 40% of total energy consumption and around 75% of them are energy inefficient, with an annual renovating rate around 0.4-1.2%. EU has established legislative frameworks as EPBD (directive 2010/31/EU and update) and EED (2012/27/EU) in order to increase the energy performance of the buildings and has required the nearly zero energy building (nZEB) target for public buildings starting from January 2019. A nZEB is a very high energy performance building with nearly zero or very low amount of energy required that should be covered by on-site or nearby energy production from renewable sources (EPBD).


From one hand, the achievement of the nZEB target is very complex in new buildings and the level of difficulty rises in case of energy renovation of existing buildings, where the implementation of the renovation measures is limited. The renovation process to high energy performance, or nZEBs target, is reduced by social (lack of trustworthy information or lack of skilled worker or doubts on the possible benefits), economic (energy savings are not clear or guarantee and the investment results reduced), and financial (scarce capital or limited financing scheme available or knowledge) barriers.


Nevertheless, achieve the nZEB target means increasing living comfort and quality of life of tenants, reducing the use of carbon technological solutions and favoring the clean energy transition.


EPBD requires the energy performance certificate for building during buying and selling of real estate activities: Energy performance certificate is an energy rating instrument completed of energy consumption data, recommendations and costs-effective improvements; it should be useful by everyone, professional and non-professionals’ experts to compare energy consumption of several buildings and able to affect the final quality value of the property. It plays an important role when it comes to the transition to clean energy use. But there are still unsolved questions:


  • How deep is the nZEB target penetration in buildings market during the renovation processes in Central Europe countries (Austria, Croatia, the Czech Republic, Germany, Hungary, Italy, Poland, Slovakia and Slovenia)?
  • What are the limits that reduce the nZEB target penetration in the building sector?
  • Are public authorities able to achieve the nZEB target during the renovation process of public buildings?

Within Interreg Central Europe eCentral project was organized a survey for building experts in order to identify the state of the art of the nZEB target implementation in the renovation processes of existing buildings.  eCentral project, financed by Interreg Central Europe programme, aims to support public authorities to pursue EU target, increasing energy efficiency and renewable energy use in renovation of existing public buildings with innovative financing schemes that need to achieve the nZEB target.


48 were the survey participants, and a main result was an overview on of the nZEB target implementation in the renovation process of existing buildings, in particular:


  • nZEB target implementation in eCentral partners ‘countries (IT, AT, HR, HU, SL) considering the adopted regulations;
  • calculation tools used to analyse the energy performance of the buildings and the cost-optimality of the renovation measures and energy performance certificates (EPC);
  • possible economic instruments for energy renovations to capture opinions on used financial incentives in the CE target countries.

nZBE target overview


The nZBE definition for residential and non-residential buildings, in new or existing buildings, in CE countries is been implemented in different way: some countries use absolute numerical indicators (as Czech Republic, Germany, etc.) while other ones used a reference building (as Italy) to determinate the maximum value of several indexes (as primary energy demand), Table 1.


37% participants confirmed to know if there are policies adopted at national (regional) level to integrate the nZEB target in existing buildings in case of renovation.


The eCentral project has evidenced that despite the refurbishment of building stock is critical to reach EU level goals for improving energy efficiency and cutting CO2 emissions, the high level of missing information on nZEB definition and minimum requirements for the renovation process of existing buildings is evident: only some countries like Austria, Italy and Slovenia have already defined nZEB requirements for building renovations.


In the survey, half of participants (52% energy experts, 27% public representatives and 13% building professionals, 8% others) stated to have already worked in the design or construction process of new or renovated nearly zero energy buildings, and one public representative of two confirms to have this experience.


Questionnaires to stakeholders highlight the need to increase measures and initiatives to boost and facilitate the nZEB implementation process as increase the knowledge of each stakeholder involved in the renovation process from the owner to the building professional, and increase the guarantee on the energy savings planned through a structured process based on checks and verification actions during the building design, construction, and service life phases..


Energy performance certificates (EPC)


Energy Performance Certification (EPC) is a crucial instrument to enhance the energy performance of the buildings (art. 11-13 of Directive 2010/31/EU). EPCs should be useful instruments for stakeholders (including final users), enabling to compare building energy performances within a purchasing/renting decision process. Unfortunately, EPCs may be difficult to understand for non-professionals and the general public which lead to a negative impact on their use during the renovation or selling and rental processes. EPC will should include data on: energy performance, annual energy consumption, energy from renewable sources of the building or building unit and recommendations for the cost-optimal or cost-effective improvements of energy performance of the building or building unit, completed of payback periods or cost-benefit over economic lifecycle period. Starting from these considerations eCentral survey investigated the current utilization of EPC instrument: positive and negative aspects, barriers and limits.


It was found that:


  • A very positive result is that 96% of the participants know what an EPC is. This is in line with the EPBD: EPCs should be mandatory in EU countries.
  • 75% of the survey participants consider EPC as a useful and easy-to-use instrument to understand the energy efficiency of a building, but at the same time, EPC results an “additional paperwork and excessive bureaucracy” (62%) and increases the “costs for owners/investors” (64%). Only the 46% of participants considers EPC an effective tool that can be used by non-professional users as well.


In parallel achieve the nZEB target requires the development of new design approach that focuses more on the energy flows in buildings and requires a more dynamic and holistic approach in all topics. On this regard, within eCentral project were analyzed the existing nZEB tools used in the project partners countries to determine the deep renovation measures of public buildings. The results show that a useful nZEB tool for existing buildings needs to have some features: from one side it should be an easy decision support tool for approaching cost optimized nZEB refurbishment strategies completed of database continuous update on case studies, solutions sets (energy performance features and relative costs), and LCC, and from the other one a high quality use-friendly tool for building experts, owner and tenants.


Economic instruments for energy renovations


Economic instruments for energy renovations are manifold and can be divided between (i) financial instruments such as loans, grants and subsidies, (ii) fiscal instruments such as tax credits or (iii) VAT reductions and market-based instruments such as energy saving obligations or white certificates.


In Table 2 an overview of the economic instrument on energy efficiency investments in existing buildings operating in the year 2013 is shown. Most of the economic instruments targeted in the residential sectors are grants/subsidies, followed by loans. Only in Italy Tax incentives or Energy Efficiency Obligation (EEO) and White Certificate (WC) are used. EEO/WC are set up only in a handful of Member States, but this is likely to change with the implementation of the Energy Efficiency Directive (2012/27/EU) and introduction of article 7 on energy efficiency obligations.


The participants of the survey find that improvement of the economic instruments (grants/subsidies, loans, tax incentives, energy efficiency obligations and white certificates) for investors/owners/tenants and simplification of the procedure for obtaining economic instruments are the most important measures to stimulate energy efficiency renovations. Improvement of the national frameworks with easy, accessible and appropriate indicators and to share the risks between investor and tenant in case of energy savings are lower than expected are also considered useful in this regard.


To realize the full potential of nZEB standard, public funds will not be sufficient and innovative third-party financing and investing models such as PPP, EPC and crowdfunding will have to be unlocked at a larger scale. Another result coming from eCentral project is that the decision-making tree of analyzed financing schemes is strictly connected with the public monetary resources available, payback time of the investments, internal personnel resources and risks.


Regarding the policy frameworks for these financing schemes, positive improvements have been recorded in most target countries although differences between markets are extremely high, mostly due to uneven development of financial markets and national policies which regulate each financing model.


Conclusions and recommendations


Starting from the nZEB definition and its implementation in the building sectors, at the state of the art, only three countries involved in eCentral project as Austria, Italy and Slovenian have already defined a nZEB definition for residential and non-residential buildings, new or existing one.


Reaching EU energy efficiency goals results a complex task that includes different professionals’ skills (public representatives, architects, engineers, constructors, investors, tenants…). Investment in action and initiatives able to increase the knowledge of the building design and construction professionals (architects, engineers…) and final tenants that for first affects the energy consumption with their user behavior. Despite achieve the nZEB target is an important and necessary strategy to adopt in CE countries. In particular, public authorities play an important role, because they have to demonstrate for first that achieve the nZEB target in renovation of existing public building is possible, and one public representative over two confirmed to have this experience.


On the other hand, more guarantees on the energy savings planned are required, also using a certification protocol or specific instruments to monitor, verify and guarantee the earned savings during the lifetime of the building. In this regard, benefits come from nZEB target should be real and concrete, in terms of energy savings and comfort. Energy Performance Certificate can be considered one of the most important European instrument, able to enhance the energy performance of the buildings, and mandatory required by EPBD. Increase and facilitate the use of public incentives in case of energy efficiency achievements is a good strategy to boost the investments in the renovation of existing buildings.


Attached to the text

Table 1: Overview nZEB-definitions in Central Europe. Source: eCentral project deliverable D.T1.1.1 Report on nZEB initiatives from the Central Europe region, based on data from, and statements of eCentral project partners.

Table 2. Economic instruments on energy efficiency investments in existing buildings operating in the year 2013. Source:

Figure 1. Important initiatives to increase in order to facilitate the achievement and implementation of nZEB target in renovation process.