Harmonizing Key Performance Indicators for the Next Generation of Energy Performance Certificates (EPC)

 a comprehensive overview of the new CEN Workshop Agreement CWA 18127:2024

Keywords: standardization; EPC; KPI; sustainability; EPBD

The next generation of energy performance assessments and certificates ought to address the transformation into an era where an increasing amount of data are available on the operational use of buildings, and the buildings can be observed with ever increasing details via a larger number of stakeholders.

The EuB SuperHub project (https://eubsuperhub.eu/) has supported the evolvement of the certification process in the EU through the development of a scalable methodology supported by an online platform to view, assess and monitor the buildings through their lifecycle in relation to an expanded set of indicators that go beyond the energy performance in the occupation stage (embedded energy, costs etc.).

The EU Level(s) initiative is already leading a way of a new, holistic view of the buildings taking into account sustainability principles (LCA, LCC etc.). Energy performance assessments and certificates of buildings therefore need to evolve to reflect the technological development, the needs of society, and within the EU, they must be consistent throughout Member States.

Holistic vision of buildings, social and technological changes in society require a change in the way we look at and manage the built environment, also encouraging public investments and incentives to improve the energy efficiency of assets. EUB SuperHub project tied the “distributed” systems, assessment schemes and certifications spread across Member States, based on common criteria (e.g. Level(s), SRIs, EVCS) through a digital one-stop shop platform.

The EuB SuperHub platform is intended to store, geo reference, display and organise the local public databases of EPC (Energy Performance Certificates), local sustainability and SRI (smart readiness indicators) ratings into a common digital “e-passport”.

The EuB SuperHub e-passport is intended to be supported by a digital building logbook (materials used, HVAC systems, previous renovations, BIM files, etc.) and utilize the latest cutting-edge assessment techniques and innovative criteria - smart readiness, materials logbook for circular economy, LCC etc. - to boost transparency, reliability, and count on comparable good quality certifications. The project partners ‘countries cover many climates, building typologies and construction types, sustainability and EPC scheme operators; the EuB SuperHub consortium was able to collect a large number of building (certificate and assessment) samples and store them in the geo-located cloud database.

Moreover, through adopting a bottom-up and a top-down approach (benefitting system operators’ and assessors’ experience) in the online deployment of the next generation holistic building assessment, the transparency and engagement between the policy makers, the funding agencies, the specialists and the building user was ensured throughout the entire project duration.

One of the main results of the project has been the development of a new European pre-standardization document: the CWA 18127:2024 “EUB SuperHub - A harmonization of KPIs for supporting the next generation of EPCs”, aimed at creating a harmonized system of Key Performance Indicators (KPIs) for Energy Performance Certificates (EPCs). This document provides an essential reference framework to support the next generation of EPCs by ensuring consistency, interoperability, and a holistic approach to assessing the energy performance of buildings. The document is freely accessible and downloadable from the CEN website (https://www.cencenelec.eu/get-involved/research-and-innovation/horizon-europe-projects/cwa-download-area/).

Background and Objectives

The CWA 18127:2024 emerges from the need to enhance the effectiveness of EPCs across the European Union (EU). The European Commission’s Renovation Wave Strategy, launched in 2020, underscores the urgency of increasing the rate and depth of building renovations to achieve climate neutrality by 2050. In response, the EUB SuperHub project, funded under Horizon 2020, has proposed a harmonized framework to improve the quality, visibility, and usability of EPCs across Member States (MS).

By addressing existing discrepancies among national EPC systems, this initiative ensures a more unified and efficient approach to building performance assessment, aligning with the Energy Performance of Buildings Directive (EPBD 2018).

Scope of CWA 18127:2024

The document defines a transnational set of KPIs designed to evaluate energy performance, sustainability, and smartness in buildings. These indicators contribute to a digital building logbook and facilitate the creation of a harmonized ‘building e-passport.’ The framework serves various stakeholders, including policymakers, building owners, and energy professionals, by providing clear and actionable data for decision-making.

A Holistic and Integrated Approach

The CWA 18127:2024 adopts a comprehensive evaluation methodology, considering multiple interconnected factors influencing building performance. The traditional focus on energy consumption is expanded to include environmental, social, and economic dimensions.

Key motivations for this holistic approach include:

·         Environmental Stewardship: Addressing climate change impacts and promoting sustainable building practices.

·         Technological Evolution: Incorporating smart technologies that optimize energy use and operational efficiency.

·         Occupant Health and Well-being: Ensuring buildings support a healthy indoor environment.

·         Energy Security and Autonomy: Encouraging on-site energy generation and storage solutions.

·         Regulatory Compliance: Aligning with evolving EU standards and legislation.

·         Economic Considerations: Assessing long-term cost efficiency and return on investment.

The CWA identifies 21 KPIs grouped into ten thematic areas, each addressing crucial aspects of building performance:

1. Energy Consumption

·         Delivered annual energy per area unit

·         Total annual primary energy use per area unit (self-used)

·         Non-renewable annual primary energy use per area unit (self-used)

·         Embodied energy

2. Renewable Energy

·         Renewable annual primary energy use per area unit (self-used)

·         Renewable energy ratio (on-site, nearby)

3. GHG Emissions

·         Operational greenhouse gas emissions

·         Life Cycle Global Warming Potential (GWP)

4. Thermal Comfort

·         Percentage of time outside of thermal comfort range

5. Indoor Air Quality

·         Ventilation rate

·         CO₂ concentration

·         Relative humidity

·         Total VOCs and specific harmful pollutants

6. Costs

·         Operational energy cost

7. Smart Buildings

·         Smart Readiness Indicator (SRI)

8. Resilience to Overheating

·         Summer thermal discomfort in 2050 projections

9. E-Mobility

·         Percentage of recharging points and pre-cabling for electric vehicles

10. Daylight Sufficiency

·         Assessment of daylight provision

To facilitate consistent evaluation, each KPI is documented in a structured template outlining:

·         Definition and scope

·         System boundary and unit of measurement

·         Applicable standards, calculation methods and comparability of the results

·         Required data sources and assessor competencies

For example, the Delivered Annual Energy per Area Unit KPI considers both calculated (asset-based) and measured (operational) assessment methods. The framework allows for comparability across different climates and building types by standardizing reference conditions and energy factors.

The selection process followed a bottom-up approach, incorporating stakeholder consultations, initiatives from the European Commission and existing standardization efforts.

This to ensure that the final set of KPIs can effectively support the relevant EU legislations; it is applicable by the market stakeholders and relevant to them; with the final aim to support the strategy for an energy transition in the building sector.

The adoption of the CWA 18127:2024 has significant implications for the future of EPCs in Europe. By fostering standardization and digitalization, the framework enhances transparency and facilitates the integration of advanced energy management systems.

TheCWA 18127:2024 represents a major step forward in harmonizing EPCs across the EU. By establishing a robust set of KPIs and aligning with the latest policy developments, it paves the way for more effective energy performance assessment and sustainable building practices. The EUB SuperHub initiative sets a precedent for future innovations in the field, ensuring that Europe moves towards its climate goals with a clear and actionable framework. The expected outcomes include indeed streamlining data collection and analysis to support renovation decisions; providing clearer and more reliable EPCs for real estate transactions; while enhancing policy implementation.

CWA 18127:2024 EUB SuperHub - A harmonization of KPIs for supporting the next generation of EPCs.