CO2NSTRUCT: Modelling the role of circular economy construction value chains for a carbon-neutral Europe

Project Information

CO2NSTRUCT

Grant agreement ID: 101056862

DOI

10.3030/101056862

EC signature date 4 May 2022

Start date 1 June 2022

End date 30 September 2026

Funded under

• Climate, Energy and Mobility

Total cost

€ 4 379 838,75

EU contribution

€ 4 377 332,00

Coordinated by

DANMARKS TEKNISKE UNIVERSITET
Denmark

Periodic Reporting for period 2 - CO2NSTRUCT (CO2NSTRUCT: Modelling the role of circular economy construction value chains for a carbon-neutral Europe)

Reporting period: 2023-12-01 to 2025-05-31

Summary of the context and overall objectives of the project

The overarching goal of CO2NSTRUCT is to answer the question: how can climate mitigation (CM) be achieved using circular economy (CE) practices within the construction industry? To do this, we need to understand which CE practices, in fact, contribute to mitigating carbon emissions. To understand how the new CE paradigm changes the existing one, we need to define and quantify the baseline of material flows, carbon, water, embodied energy of materials across six carbon-intensive construction materials value chains (Objective 1). Next, we try to understand how CE is being perceived and adopted by citizens (Objective 2), so that we can better inform future scenarios of CE preferences in the construction sector. Of course, CE practices will change the baseline value chains, adding processes and transportation to the supply chain. CO2NSTRUCT will then map the supply chains of the six carbon-intensive construction materials (objective 3). One key aspect of this project will be to understand the rebound effects of CE by quantifying the unexpected market, behavioural and industrial responses to the identified CE practices (Objective 4). Once all this data is in place, we will then disaggregate the CM energy model – JRC-EU-TIMES model – as well as other sustainability models/tools and redesign a new enhanced CM model/framework that incorporates the new flows, trade-offs, costs and energy consumption of CE (for the construction sector) (Objective 5). The enhanced CM model/framework is then ready to run with different circular mitigation scenarios for 2070 and estimating the impacts in greenhouse gases emissions (Objective 6).

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

CO2NSTRUCT aims to redesign the linear framework of climate mitigation models by focusing on one section of the economy/market: the construction industry. By focusing on 6 pervasive and/or carbon-intensive construction materials, we map the complete value chains of cement, steel, brick, glass, wood, and insulation materials. Because there are several sub-classes of materials within the 6 chosen materials, we had to divide the materials further into 12 subclasses, doubling the effort for all subsequent tasks in WP1, WP3, and WP5. So far, we have organized data in subcategories but have yet to reach a beta version of the database (milestone 1, WP1). We have revised circular economy practices for 6 of the 12 subclasses of materials, validated by the UB, and provided the supply chain mapping of 8 sub-classes (Steel, CEM 1, Steel, Glass/Stone Wool and EPS, Sawn Wood) of 8 sub-classes (Flat Glass, Brick, Steel, CEM 1, Glass Wool-Stone Wool-EPS, Wood) (milestone 5, WP3). Redesigning the energy-climate mitigation model TIMES framework requires several iterations of the concept. For this, we needed to identify buildings (Cluster 1) and offshore (cluster 2) CE practices and redesign the building industry within the TIMES model. This requires extra effort from WP1, WP3, and an early start of WP5. A key aspect contributing to the definition of scenarios that the TIMES model and framework will consider was identifying policies that bridge climate mitigation and circular economy (Task 2.4) and formulating the citizen behaviour survey (milestone 3, WP2). To map current practices in the development of stakeholders focused on CE analysis, an expert web survey is conducted, considering various assessment frameworks. Furthermore, a database of CE experts is compiled (Task 5.1). The objective of this survey is to identify discrepancies between research findings (Task 3.2) and current practices. Additionally, it aims to provide input to the TIMES model by defining the most representative circular climate mitigation scenarios (Task 6.1) and outlining strategies for their integration (Task 6.2).

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

CO2NSTRUCT describes in the GA as main results: (i) a curated database, (ii) a survey about citizen behaviour about CE measures in the construction industry, (iii) value chains maps of the six carbon-intensive construction materials with CE practices, (iv) quantification of CE social and environmental rebound effects, that will then lead to (v) an augmented TIMES energy-climate mitigation model. From these results, we are making good strides in achieving them. We expect slight delays in (i) and (iii) but we describe how we will mitigate them in sections 1.2 and 5.1. Regarding impacts, we have foreseen results in all domains (scientific, economic, societal, and policy). So far, we have engaged with 15 stakeholders spread throughout the industry, policy-makers, and institutional and academic – members of our advisory and end-user boards (Table 8 in the periodic report) in workshops and interviews. The project has been presented at various scientific conferences and workshops (with 18 scientific outputs) and was invited to a high-impact journal seminar series (Resources Conservation and Recycling, Elsevier) for a talk, with a high appraisal. So far, and as planned, we have not yet results about mitigation. Once we have, we will engage with more policy-makers, standardization institutions and the general public in order to divulge which circular economy practices to adopt in the construction industry to practice “sustainable” climate mitigation.