• Energy Research

Abstract Building energy performance requirements aiming at the nZEB target have been recently established by the national legislation. In Italy, the requirements are verified through the notional reference building, whose U-values are reduced in two steps: up to 2018 and since 2019 for public buildings, and up to 2020 and since 2021 for all other buildings. This might cause a reduction of the heating need but an increase of the cooling need. The objective of the study is to investigate in which conditions and extent a significant imbalance of the energy needs occurs. Different building types and climatic zones are considered.

AbstractThe objective of the IEE-EPISCOPE project is to make the energy refurbishment processes in the European housing sector more transparent and effective. Each participating country is developing a pilot action, aiming at tracking the refurbishment progress of housing stocks at different scales. In the present article, the monitoring of the Piedmont regional housing stock is concerned. A preliminary analysis on data sources is performed, to identify the current state of the stock and the refurbishment rates. The results are a basis to carry out energy performance calculations and to assess future refurbishment scenarios and quantify the energy saving potentials.

The European building sector significantly contributes to the EU’s greenhouse gas reduction goals, with the 2024 Energy Performance of Buildings Directive (EPBD) aiming to achieve a decarbonised building stock by 2050. By focusing on an existing office building representative of the Italian building stock, this research evaluates various energy efficiency measures and integrates renewable energy systems to transform the building into a Zero-emission Building (ZeB). Moreover, it also utilises future weather data to address the effects of climate change. Results highlight the actions needed for an empirical ZeB transition, offering insights into challenges and key performance indicators across different intervention scenarios. The findings contribute to establishing national ZeB standards, emphasising the importance of the national building renovation plan in compliance with the EPBD recast requirements.

Abstract The EU Member States are being involved to develop long-term strategies and to promote investments aimed at improving the energy efficiency of the building stock, at increasing the use of Renewable Energy Sources (RES) and at growing the number of Nearly Zero-Energy Buildings (NZEBs). The aim of this article is to investigate energy and economic implications related to the exploitation of RES in the transformation of an Italian social housing building-type into a NZEB. The research is based on a detailed energy audit procedure that includes cost-optimal assessment and compliance check with the legal requirements. A parametric analysis was performed to find out the technical building system configurations that verify the minimum share of RES established by the Italian regulations, and at the same time to assess global cost and payback period. The intersection between legal compliancy and cost-effectiveness narrows the field of applicable RES technologies that are limited to electric heat pump for heating and cooling coupled with PV system, and low size solar collectors coupled with low temperature generator for domestic hot water. Improvements in the energy policy are necessary to guarantee the best trade-off between RES exploitation, energy efficiency and costs, as to preserve market equilibrium.

AbstractDirective 2010/31/EU establishes that Member States must ensure that minimum energy performance requirements for buildings are set with a view to achieve cost-optimal levels. The paper presents a methodology for identifying the cost-optimal levels for the Italian residential building stock, following the Guidelines accompanying the Commission Delegated Regulation No. 244/2012. The methodology is applied to a reference building of the IEE-TABULA project and considering different energy efficiency measures. The energy performance and the global cost calculations are performed according to UNI/TS 11300 and UNI EN 15459, respectively. A new cost optimisation procedure based on a sequential search-optimisation technique considering discrete options is applied.

The Italian National Annex (NA) to EN ISO 52016-1 is aimed at improving the simplified hourly calculation method of the building thermal performance assessment by introducing different modelling options. The present work deepens the influence of the Italian NA improved method on the thermal energy needs for heating and cooling of a residential building-type in two different climate zones. In particular, the Italian NA improved options are applied one-at-the-time, and their effect is evaluated in comparison with the EN ISO 52016-1 standard method. The use of solar angle and time dependent correction factors for the total solar energy transmittance of glazing proved to be the most sensitive modelling option, among those analysed. Negligible variations were instead reported for the other tested options.

Deliverable 3.2 summarises the work done and the results achieved in Task 3.2 Structuring available data according to energy standards, carried out within Work Package 3 - Energy data modelling. Tasks 3.2 provides the ontological modelling of energy data (i.e. energy systems, energy quantities and boundary conditions) identified in Task 2.1 Case study design, applying the data categorisation and the terminology defined in Task 3.1 Providing access to distributed energy data repositories.Task 3.2 is developed in parallel with Task 3.3 Structuring contextual data according to standards because they both concern the data modelling: Task 3.2 is about the energy data, while Task 3.3 is about the energy related data or contextual data. The present deliverable concerns the guidelines for structuring energy data, while Deliverable 3.3 (due month 18) will contain the guidelines for structuring contextual data. The development of the ontology is the basis for the creation of the SEIF (Semantic Energy Information Framework) in WP4, which will facilitate access to distributed energy data for the tools developed in WP5. Deliverable 3.2 deals with the following items:- The identification of the categories of data to be semantically modelled.- The analysis of the main international standards for energy data modelling.- The definition of the ontology structure and the creation of the Standard Tables.- The elaboration of Mapping Tables to create correspondence between the ontology and input data deriving from the data sources or from the tools. The following project partners have been involved in Task 3.2: POLITO, FUNITEC, UoT, CIMNE and HAS. Deliverable 3.2 has been elaborated by POLITO, which is the leader both of Task 3.2 and of the entire WP3. The information on data have been provided by the partners responsible for the case studies: RAMBOLL, NEA, UoT, CIMNE and FORUM. Task 3.2 gives a fundamental contribution to the development of the Use Case methodology (Deliverable 1.8) as the core of SEMANCO. In fact, all the input data and the outputs in the Activities belonging to the Use Cases related to energy systems, energy quantities and boundary conditions were semantically modelled in Task 3.2, and Deliverable 3.2 provides the guidelines that have been followed to achieve this goal.

Abstract The article presents the fundamental steps of building refurbishment toward the nZEB target; it is based on a detailed energy audit and on a financial analysis. The methodology starts from the set-up of a numerical model of the building, calibrated through actual data on operation, climate and energy consumption. Then, a cost-optimisation procedure is applied to identify the energy efficiency measures that determine the minimum global cost in 30 years lifetime. Finally, the measures are improved as to comply with the nZEB requirements and to be cost-effective as well. The methodology was applied to a high school in Torino.