Evaluating the Energy Readiness of National Building Stocks Through Benchmarking

Abstract

Evaluating the energy performance of existing buildings is critical for improving the efficiency and resilience of the building stock as a whole. The importance of this information holds at different scales, both locally and at the national and international levels. A major problem arises from the difficulty in obtaining information from existing buildings; often, the only available data are the yearly consumption per unit area, typically corresponding to the energy performance certificate (EPC). This paper shows how to address concerns of practical relevance with a limited number of variables by examining an EPC national database (including the major cities of Tallinn, Pärnu, Tartu, and others) that provides only EPCs, construction/renovation year and heated area. Through a systematic statistical investigation of nearly 35 000 EPCs of educational, office, commercial and other building typologies, we i) characterise the time evolution of EPC classes, ii) evaluate the impact of incentives pre/post-renovations, and iii) create benchmarking tables that allow comparisons of a specific building with the existing stock to identify representative buildings for detailed auditing. The readiness of the Estonian building stock could thus be evaluated by linear fitting. All new and renovated buildings are estimated to achieve the zero-energy building (ZEB) status by 2050; remarkably, for some categories, this will occur already in the present decade if the identified linear trends persist. Additionally, we investigated whether the COVID-19 pandemic has affected building stock readiness by comparing pre-and post-2020 ZEB year fit estimations. Contrary to what was expected, the change in working habits affected some building types only marginally, while the national regulations played a prominent role. Detached private houses exhibited a pronounced worsening in readiness, while the educational and entertainment sectors benefited from specific energy labelling remodulations.INDEX TERMS Benchmark testing, energy consumption, energy management, energy efficiency, statistical analysis.

Assessing Energy Performance Certificates for Buildings: A Fuzzy Set Qualitative Comparative Analysis (fsQCA) of Portuguese Municipalities

“…However, these incentives for energy-efficient measures were primarily targeted at environmentally conscious homebuyers. Other authors, such as Mudgal et al [7], Gómez-Román et al [24], Gardner and Stern [36], Mills and Schleich [37], Poortinga et al [38], Nair et al [39], Ferrantelli and Kurnitsk [45], Belaïd et al [46], and Stern [47], have also investigated the effect of energy consumption, prices, and environmental concerns on energy efficiency in households.…”

Energy Performance Certificate Classes Rating Methods Tested with Data: How Does the Application of Minimum Energy Performance Standards to Worst-Performing Buildings Affect Renovation Rates, Costs, Emissions, Energy Consumption?

“…The main problems range from the performance gap, namely the EPCs' accuracy in relation to real energy data [17], to consistency of the EPCs; it is indeed critical to the EPBD that for any building, a replicable and standardised assessment is carried out in the same way. For instance, a recent comparison of computed versus measured EPC values for the Estonian building stock revealed that time-related behaviours can be quite different [14]. Furthermore, it was argued in [16] that steady-state modelling is unable to model dynamic aspects of energy usage, inducing a sort of inertia that restricts embedding the latest research on energy modelling within frameworks of energy assessment.…”

“…Since the EU countries mostly favour renovations from G to F by 2027-2030, and from F to E in 2033, the way the scaling applies to the worst-performing classes is of paramount interest. As it was recently shown, a country's own energy labelling regulations can dramatically affect renovations, contracting [11] and the energy performance of all building types [14,21]. This also has a sizeable impact on CO 2 emissions, as illustrated in [22], and on management policy as well: setting minimum requirements in the national implementation of the EPBD recast will in fact determine how many buildings must be upgraded out of the G and F classes.…”

“…The commercial buildings cluster corresponds to various types of stores of different scale (from small bakeries to shopping centres) and to beauty, vehicle, and personal services buildings. The entire database, featuring a total of 11 building categories, was analysed in very much detail in [14], including raw data analysis and long-time energy performance predictions. Table 1 summarises the basic parameters of the dataset.…”

“…The EPCs are defined as the measured or calculated energy consumption of a building over a certain amount of time (often, annually). In the European Union (EU), these are commonly rated from A to G (smallest to largest, hence best to worst) [12], and provide a very strong tool for assessing the energy performance of national building stocks [13,14].…”