Energy and emissions

Around 34 per cent of global energy consumption and almost 40 per cent of the associated greenhouse gas emissions are attributable to the building sector – both during the construction and operational phases. In addition to the emissions we generate directly, we have set ourselves the target of also reducing CO_₂e emissions along our upstream and downstream value chain.

Our emissions

The STRABAG CO_₂e footprint, also known as the corporate carbon footprint, comprises emissions from various areas. Of these, around 10 per cent are direct and energy-related (Scope 1 and 2) emissions. Around 90 per cent of our emissions arise along the upstream and downstream value chain (Scope 3 emissions). 
 
We are aware that, particularly in the area of Scope 3 emissions, there is a high degree of dependence on external factors which are not solely within our control, such as the decarbonisation targets of our suppliers and clients, as well as technological and market developments in the field of low-emission building materials. Given these uncertainties, we are committed to transparently setting out the reduction potentials that can currently be expected.

STRABAG’s climate targets

Short-term target by 2030

We are convinced that credible climate targets must be science-based, in accordance with uniform standards and externally validated. The Science Based Targets initiative (SBTi) has validated STRABAG’s short-term climate targets. This means that STRABAG is committed to reducing its absolute Scope 1 and Scope 2 emissions by 42 per cent by 2030 compared to the base year 2023.* In addition, STRABAG’s Scope 3 emissions, which result from the purchase of goods and services as well as the use of products sold, are to be reduced by 25 per cent over the same period.

*The target boundary includes land-related emissions and removals from biogenic.

Target for 2040

We are consistently pursuing our reduction strategy beyond 2030. Our ongoing target, approved by the STRABAG SE Management Board, is to achieve climate neutrality in our own operations by 2040.

We are not currently setting any specific targets for emissions reductions along the value chain beyond 2030. The decarbonisation of our value chain is, to a large extent, beyond our own sphere of influence; therefore, we do not wish to make any promises that cannot currently be substantiated. This includes, for example, the sufficient availability of near-zero-carbon building materials and the long-term market demand for CO₂e reduced buildings. One thing is certain for us: we are working to increase the existing potential and tap into it as early as possible.
 
The progress of our targets is reviewed once a year and reported to the Management Board and the Supervisory Board of STRABAG SE. Where necessary, it is adapted to new technological, regulatory and market conditions.

How we are achieving our climate targets: Our transformation plan in detail

To achieve our climate targets, the Management Board of STRABAG SE has adopted reduction pathways for decarbonisation. These form part of our sustainability strategy and outline the CO_₂e reduction potential for Scope 1 and 2 emissions, as well as our Scope 3 emissions.

Reducing our direct and energy-related emissions (Scope 1 & 2)

To implement the reduction targets for our Scope 1 and 2 emissions, we have identified seven key areas of action which account for the largest share of our CO₂e emissions and thus represent the key levers for reducing emissions.

Emissions reductions will result from the substitution of fossil fuels with renewable or lower-emission alternatives, as well as from efficiency improvements through the use of new technologies (e.g. electrification).

Areas of action for emissions reduction

For each of the seven areas for action, a specific energy target scenario has been developed, based on assumptions regarding technological developments and the future availability of energy sources and their infrastructure. These assumptions were derived primarily from studies, market scenarios and internal expert assessments.

• Buildings: Group-used administrative sites (both owned and leased) can be operated without fossil fuels by 2040. A key prerequisite for this is the transition, as far as possible, to electricity-based heating and cooling systems. For certain applications, the use of biomass-based energy sources is also planned.
• Passenger cars & commercial vehicles: Just under half of the fleet is to be electrified by 2030, and the aim is to achieve extensive electrification by 2040. For applications that are not expected to be electrifiable, the use of renewable fuels is being considered as an option.  
• Construction power & other construction energy: The aim is to achieve a comprehensive electricity-based energy supply for our construction sites by 2040, with two-thirds of small equipment to be electrified as early as 2030.
• Construction machinery & lorries: The aim is to decarbonise around two-thirds of construction machinery by 2030 using renewable fuels, in particular HVO100, as well as through initial electrification measures. A significant increase in the level of electrification is anticipated by 2040. Based on current planning, we anticipate that around half of these will be able to run on electricity by then. For applications that are not expected to be electrifiable, renewable fuels and alternative technologies, such as hydrogen, are being considered as decarbonisation options.
• Asphalt mixing plants: For around two-thirds of our asphalt mixing plants, the aim is to switch to lower CO₂e or renewable energy sources by 2040. The current modelling is based on a technology mix comprising biomass, HVO100, electricity and hydrogen. Based on current knowledge, we also expect around one-third of the plants to continue using fossil fuels in 2040.
• Stone and gravel quarries: The stone and gravel quarries, which are already predominantly electrified today, are to be largely converted to an electricity supply from renewable energy sources by 2040.
• Concrete plants & other production facilities: We aim to gradually transition our concrete plants and other production facilities to renewable energy sources by 2040. The current modelling is based primarily on electrification, supplemented by biomass and HVO100.

Note on our assumptions and forecasts

Our aim is to deploy low-emission technologies across all relevant areas of activity and to actively drive forward the conversion of our facilities and processes. In certain areas, however – particularly with regard to production facilities and parts of our machinery fleet – actual implementation also depends on technological advancements, market readiness, availability and the cost-effectiveness of the relevant solutions.
 
The timing and extent of these developments are therefore subject to uncertainty and may influence the actual achievement of our targets. For this reason, the underlying data and framework conditions are evaluated annually so that we can adjust the target pathways accordingly where necessary.

Projects and initiatives to reduce our Scope 1 and 2 emissions

As part of Group-wide initiatives, pilot projects and feasibility studies, STRABAG is working consistently to drive forward the necessary transformation measures in a targeted manner to achieve our climate targets. In addition to the electrification of processes and plant – where this is already technically and economically feasible in some cases – and the coordinated expansion of photovoltaic systems at our sites, STRABAG is testing innovative technologies and alternative energy sources. The aim is to gradually incorporate successful solutions into Group-wide standards and processes. Particular focus is placed on the heavy construction machinery sector, where, in addition to electric drive systems, hydrogen-based systems are also being investigated and tested as potential alternatives. Furthermore, production facilities are being progressively converted to lower-emission technologies and efficiency measures are being implemented on an ongoing basis. As a result, in the 2025 financial year, we were able to reduce Scope 1 emissions compared with 2024, despite higher output.

Reduction of emissions along the upstream and downstream supply chain (Scope 3)

STRABAG’s Scope 3 emissions account for around 90 per cent of STRABAG SE’s CO_₂e footprint. A significant contribution to this comes in particular from purchased building materials and services, as well as the use phase of the products sold. ‘Products sold’ are defined as structures erected by STRABAG as a main contractor, such as buildings or infrastructure structures. Our Scope 3 emissions reduction pathway therefore highlights the reduction potential within the action areas of structures and building materials. 

Emissions from structures refer to those emitted during the operational phase of a sold product. To calculate emissions in the building materials sector, those with the highest contribution to total CO_₂e emissions were identified. These represent the key emission drivers and offer the greatest potential for emission reduction. They include concrete, cement, stone and gravel, asphalt, steel and bitumen.

Measures to reduce emissions

We do not have the same level of influence over decisions regarding our Scope 3 emissions across all project phases and business models; for example, when comparing in-house and outsourced development work, or planning and implementation services as opposed to pure main contractor services. We therefore distinguish between direct and indirect measures for reducing emissions.

• Direct measures: Energy-efficient and recyclable buildings: In its own project developments, STRABAG aims to meet recognised building standards. In projects for third parties too, STRABAG works closely with clients to promote energy-efficient and recyclable solutions. Optimised planning and construction processes are also designed to reduce material usage.
  Use of low-emission building materials: STRABAG is working to increase the use of low-emission, recyclable and renewable building materials. In third-party developments, STRABAG brings these solutions into discussions with clients. Optimised planning and construction processes are also designed to reduce material consumption.
• Indirect measures: STRABAG works with clients and suppliers to boost demand for lower-emission solutions and improve transparency in the supply chain. To this end, we are further developing the data set on supply volumes and the environmental impact of key building materials. Research, knowledge transfer and partnerships also support the development of recyclable building materials, the reuse of building components and new recycling technologies.

Note on our assumptions and forecasts

The calculation of baseline emissions is based on data from internal calculation tools and methods, which also form the basis for our annual reporting. For selected groups of building materials, this data set was supplemented in some cases by additional data sources, such as procurement systems, in order to derive material quantities and emission contributions as reliably as possible.
 
Buildings: The EU Directive on the energy performance of buildings was used to assess emissions reductions in the building sector. It was assumed that the entry into force of the EU Directive will significantly reduce the emissions caused by buildings during their operational phase. The EU Directive stipulates that, from 2028, new public buildings must be constructed as zero-emission buildings; from 2030, this will apply to all new buildings. Similarly, existing buildings are to be gradually converted into zero-emission buildings by 2050. This EU Directive should be understood as a passive lever that is influenced without any further action on the part of STRABAG or the clients.
 
The calculation of the reduction in emissions is based on assumptions regarding the implementation and impact of the EU Directive on the energy performance of buildings. The actual trend in emissions depends, amongst other things, on the specific implementation of regulatory requirements, technological developments and other external factors. Such forecasts are subject to uncertainties over which we have no control. Our assumptions may prove to be incorrect. As a result, actual results and developments may differ from our expectations, either positively or negatively.
 
Building materials & services: To estimate possible future trends in emissions, the relevant building materials were categorised according to emission classes. Where possible, existing classification systems were used. On this basis, calculations were carried out to determine what proportion of building material volumes would need to come from lower-emission classes in future in order to achieve defined emission reductions.
 
Two reduction levers were taken into account: improving the material mix through the use of lower-emission building material variants and increasing material efficiency by reducing material usage whilst maintaining the same functionality. The resulting emission reduction was compared with the expected volume trends as set out in the business plan.
 
The underlying assumptions are based on industry roadmaps, market analyses and expert estimates. The calculation serves to illustrate potential emissions pathways and does not constitute either a forecast of actual procurement behaviour or a commitment to implementation. As STRABAG SE has only limited influence over key factors – in particular the availability of lower-emission building materials and material specifications set by clients and planners – actual developments may differ from the results presented.