The European policies on nZEBs
The EPBD, as recast in 2010 (EPBD 2010/31/EU), together with the Energy Efficiency Directive (EED 2012/27/EU) and the Renewable Energy Directive (RED 2014/53/EU) represents the key regulatory framework adopted at EU level to promote an increase of energy efficiency and renewable energy production.
Energy Efficiency Directive (EED 2012/27/EU)
In October 2012, EU adopted the Energy Efficiency Directive 2012/27/EU. It established a set of measures for the promotion of energy efficiency, at all stages of the energy chain, starting from the production to final consumption. The aim is to achieve the target of 20% of energy savings by 2020. In November 2016, the European Commission proposed an update to this Directive, including a new 30% target by 2030.
The Directive applies minimum requirements and objectives, which are complementary to the indications of the EPBD 2010/31/EU; the Member States are allowed to set more tightening ones. Key measures to enhance the energy efficiency promoted by the directive are the followings:
- Energy saving efficiency targets for the Member States.
- Exemplary role of public buildings – article 5 sets binding renovation targets for public buildings.
- Energy efficiency obligations – obligations related to the previous point are also imposed. For instance, every year starting from 2014, each MS shall refurbish 3% of the buildings owned or occupied by central government.
- Energy audits and management – article 8 states that MS shall promote cost-effective, independent and high-quality energy audits for all final customers. Also, non-small and medium-sized enterprises shall implement energy or an environmental management system.
- Metering and billing – good energy consumption management requires that the consumer can easily access to data through individual metering and billing information.
- Qualification, accreditation and certification schemes, energy services and energy performance contracting, split incentives, online platform.
Although the above-mentioned measures have a higher impact on existing buildings, the application can also improve the energy efficiency of new constructions. In particular, the improvement of monitoring and billing approach as well as a structured energy management of buildings can foster the proper operation of nZEBs and guarantee the energy performance targets.
Energy Performance of Building Directive (EPBD 2010/31/EU)
The first version of the Directive was approved in December 2002 and recast in May 2010. This Directive established targets for the Member States to be fulfilled by all the new public buildings from January 2019 and all residential ones from 2021. As mentioned before, this Directive introduced the concept of nZEB and the main indications for implementation. It also added the concept of cost-optimality. Key elements of the directive are:
- Boosting the Member States to draw up National Plans towards nZEB, establishing definitions, requirements, and policies to reach the nZEB target.
- Encouraging the integration of renewable energy sources.
- Cost-optimality – Article 2.14 defines the cost-optimal level as “the energy performance level which leads to the lowest cost during the estimated economic lifecycle”.
- Energy performance certificates, introduced in the EPBD 2002/31/EC, serve as an information tool for building owners, occupiers, and real estate actors.
- Establishing regular inspections of heating and cooling systems.
- Certification of buildings, which only qualified experts are accredited to carry out independently.
Renewable Energy Directive (RED 2014/53/EU)
The Directive 2014/53/EU established an overall policy for the promotion of the energy production from renewable sources. It requires the Member States to fulfill at least 20% of its total energy consumption with energy from renewables by 2020. Also, it requires that at least 10% of transport fuels come from renewable sources. The 20% target was updated in November 2016. The new target requires at least 27% of energy from renewable energy sources in the final energy consumption by 2030.
Figure 1 summarizes the main measures promoted by the three directives that affect the path towards nZEB in Europe.
CRAVEzero Working Meeting Bolzano
CRAVEzero Kick-Off Meeting
NZEB Construction Market
The building sector in Europe is responsible for approximately 40% of the total energy consumption. The percentage accounted for residential buildings amounts at 27% of the total. Hence, this sector has a key role in the path towards the enhancement of energy efficiency and reduction of greenhouse emissions at EU level. The EPBD, together with the Energy Efficiency Directive and the Renewable Energy Directive, established a set of measures with the aim to provide in Europe the conditions for significant and long-term improvements in the energy performance of the construction market.
The EPBD established that, starting from 2021 (2019 for public buildings), all new buildings must be nZEB. On average, the volume of housing development across Europe amounts 2.8 completed apartments per 1000 citizens (Figure 1). The number of households, at European level, is expected to increase by more than 15% by 2050 compared to the number measured in 2013.
Figure 1: Number of completed dwellings per 1000 citizens (Deloitte, 2017).
A cost-effective design and operation of these new dwellings play an important role in the final energy consumption the building. Regarding technical systems, as reported in Atanasiu et al. (2011), it is evident that technologies based on fossil fuel are not consistent with nZEB concept promoted by EPBD. Electric heat pump seems to be the most suitable technology, due to the expected increase of the renewable energy share in the national electricity mix and renewable on-site production. In addition to heat pumps also biomass micro-CHPs and district heating systems (with a renewable energy share of 50% at least) will be important in the future development of the nZEB market. Figure 2 shows the share of the most used heating systems, according to the climatic zone. In cold climate a sample of 234 buildings has been collected, in mild climate 160 and in warm climate 17. In cold climates the heat pump and the district heating occupy the first two positions of the most common heating technologies, whereas the heat pump has a lower penetration in comparison with mild climates (Paoletti et al., 2017).
Other technological aspects whose improvement is necessary to push forward the market uptake of nZEB are efficient thermal insulation materials and windows, HVAC technologies. However, an analysis of BPIE showed how the actual markets related to these technologies must grow consistently to cover the future demand due to nZEBs. Table 1 shows that ventilation systems with heat recovery and triple glazed windows currently have a market about ten times smaller than the required one. The market of insulation materials, heat pumps, pellet boilers and solar thermal systems has to growth 2-3 times.
Figure 2: Share of heating systems according to climatic zones (Paoletti et al., 2017).
|Markets||Required growth factor||Current
|Insulation materials||2-3||2010||Mio €|
|Ventilation with HR||8-10||130.000||Units|
|Triple glazed windows||>10||1.500.000||m2|
|Solar thermal systems||2-3||3.700.000||m2|
Table 1: Overview of the factors actual markets should grow by to satisfy future demand (BPIE, 2011).
Finally, extra costs for nZEB construction are displayed in Figure 3. The objective of CRAVEzero project is to identify and to propose solutions to reduce these extra costs associated with the nZEB construction.
Figure 3: Extra costs for nZEBs construction versus average cost of new constructions (Pascual et al., 2016).
Atanasiu, B., & Attia, S. (2011). Principles for nearly zero-energy buildings: Paving the way for effective implementation of policy requirements. Principles for nearly Zero-energy Buildings: Paving the way for effective implementation of policy requirements, 124.
BPIE. (2015). Factsheet Nearly Zero Energy Buildings Definitions across Europe.
EU IEE ZEBRA2020 Data Tool. Available online: http://www.zebra-monitoring.enerdata.eu/ [Accessed in March 2018].
Paoletti, G., Pascual Pascuas, R., Pernetti, R., & Lollini, R. (2017). Nearly Zero Energy Buildings: An Overview of the Main Construction Features across Europe. Buildings, 7(2), 43.
Pascual, R.; Paoletti, G. (2016). Deliverable 5.1: Nearly Zero-Energy Building (nZEB) Technology Solutions, Cost Assessment and Performance. Available online: http://zebra2020.eu/publications/nzeb-technology-solutions-cost-assessment-and-performance/
Owner: HABITAT 76
ATELIER DES DEUX ANGES
Energy Concept: ZEB (regarding heating, cooling, ventilation, lighting and DHW) and PassivHaus
Location: Malaunay (France)
Construction Date: 2015
Key technologies: High-performance envelope (triple glazing, internal AND external insulation); Double-flux ventilation with heat recovery; Centralized wood boiler; PV panels
Isola Nel Verde
Owner: ISOLA NEL VERDE S.R.L.
Architect: STUDIO ASSOCIATO EUREKA!
Energy concept: COGENERATION GROUP, GEOTHERMAL HEAT PUMP, PHOTOVOLTAIC AND THERMAL SOLAR PANELS
Location: MILAN, ITALY
Construction Date: 2012
- COGENERATION GROUP
- GEOTHERMAL ENERGY (BASKET)
- GREEN ROOF
Architect: VALENTINA MORETTI
Energy concept: HEAT PUMP INTEGRATED FROM CONDENSING BOILER.
SOLAR HEATING PANEL AND VMC
Location: LODI, ITALY
Construction Date: 2014
- PRECAST COMPONENT
- COMPACT MODEL HOME
- CENTRAL CORE
- FLEXIBLE AND MODULAR
Owner: Owner´s Association
Architect: Julia Metzendorff/ Gerold Köhler
Energy concept: gas condensing heater with solar thermal warmers
- thermal insulation (16 cm polystyrene)
- best quality of heat-bridges and airtight envelope in cooperation with an energy consultant
- decentralized ventilation system with heat recovery (2 system/ apartment
- gas condensing heater with solar thermal warmers
Neue Heimat Tirol
Architect: Architekturwerkstatt din a4
cogeneration unit wood + solar thermal energy (dhw) + air system with heat recovery
2008 / 09
Owner: I.+R. Schertler Alge GmbH
Architect: Dietrich Untertrifaller Architekten
Location: Lauterach (AT) 20km south-eastern from Lindau Bodensee
Construction Date: 2011-2013
- Reversible geothermal heat pump
Owner: City of Vienna
Architect: ATP Wien
Energy concept: renewable power + environmental heat + waste heat
Construction Date: 2012
- Small electrical heat pump for utilization of server heat
- Ground water heat pump
- Small wind turbine 10 kW
BARRE - LAMBOT
ZEB (regarding heating, cooling, ventilation, lighting and SHW)
Owner: Brf Solallén (Tenant owned)
Architect: Skanska Teknik
Energy concept: Net ZEB
Location: Växjö (Sweden)
Construction Date: 2015
- Well insulated and air tight
- Balanced ventilation with heat recovery
- Ground source heat pump
- Photovoltaic panels