Scaling embodied carbon reduction across a global portfolio: Siemens Real Estate's data-driven approach

Siemens Real Estate operates as a small but strategic unit within Siemens AG, tasked with managing and developing the group's global real estate portfolio. That portfolio covers close to 8 million square meters of office and production space in more than 60 countries. Roughly a third of those assets sit in Germany, with large concentrations also in the United States, India, and China. Mirriel described the effect of that spread directly: operating "across very diverse contexts... makes scaling sustainability not only critical but also highly complex," and that complexity is what shapes Siemens Real Estate's entire approach.

The portfolio's targets sit inside Siemens' broader DEGREE sustainability framework, which spans 14 KPIs across decarbonization and energy efficiency, resource efficiency and circularity, and social priorities such as people centricity and governance. Nine of those 14 KPIs apply directly to Siemens Real Estate, which already carries a leading role in operational carbon, Scope 1 and Scope 2 emissions. Meeting Siemens' long-term climate targets, though, means going further into Scope 3, and Mirriel named upfront embodied carbon as the critical lever for that next stage.

For a portfolio this size, the challenge was never how to run a life cycle assessment. As Mirriel put it, "it's not how to do a life cycle assessment and measure embodied carbon, it's how to scale mitigation across many projects, many different teams, cultural differences, and geography." Reaching that scale meant confronting three specific barriers. Life cycle assessment typically happened too late to influence design, often becoming only a reporting exercise tied to EU Taxonomy compliance. Project data was fragmented across systems, creating manual work and no comparability between projects. And sustainability sat alongside project decisions rather than inside them, which meant it could never scale beyond whichever project team happened to be driving it. 

Siemens Real Estate's response was to move life cycle assessment to demand clarification, the stage before design work begins. Mirriel summarized the underlying principle plainly: "as long as sustainability sits next to the project, it will never scale. It has to sit inside the project." Starting that early lets the assessment enrich the initial project brief and shape both design and procurement decisions from the outset, which in turn lets Siemens Real Estate identify and finance low-carbon alternatives that work for the project and for the client. In Mirriel's words, early life cycle assessment "turned our carbon decision from a KPI into a decision driver." 

None of that shift works without a way to compare projects against each other. Siemens Real Estate's internal database, built in Power BI and connected to project reporting tools, is updated daily with new projects and tracks performance by asset type and region. It benchmarks individual projects, identifies where best practice already exists, and flags where the greatest improvement potential lies. The same dashboard feeds a procurement view, surfacing the best available solutions and their cost so project teams can work ahead of market targets rather than react to them once a project is already underway. 

The dashboard and the earlier timing both depend on one more layer: structured data at the source. Siemens Real Estate's approach is built on BIM models that carry structured data, including material types and rebar content. With that foundation in place, quantities extract automatically, materials match to Environmental Product Declarations through One Click LCA, and results feed directly into reporting, cost control, and project targets. As Mirriel summarized it, "good data, both in terms of availability and quality, made our sustainability scalable."

For Hydro, digital life cycle assessment is no Siemens Real Estate summarizes its approach in three actions: start early, structure the underlying data, and integrate sustainability into project decision making from the outset. Mirriel closed with the principle behind all three: "sustainability does not scale through ambition alone. Even if ambition is important, it scales through systems, data, and decisions." And if sustainability still shows up only as a report at the end of a project, the opportunity to act on it was already missed at the beginning.