Koninklijke Heijmans N.V.

Regulatory Filings • Jul 10, 2025

Press release

Date 10 July 2025 Page 1 of 2

Heijmans wins contract to upgrade high-voltage substation in Limburg

Construction firm Heijmans has been awarded the contract to upgrade and expand a 380kV highvoltage substation in Maasbracht, Limburg. Heijmans recently started construction work and expects to complete the project in 2029. The contract was awarded by TenneT, the operator of the national high-voltage grid. The construction project represents a revenue value of € 194 million for Heijmans.

The construction already started, but the contract has now been finalized for Heijmans. Heijmans was already involved in the design phase, during which the design for the station was developed in a construction team. The contract is part of the EU-303 framework agreement. Heijmans has previously built high-voltage substations in Krimpen aan den IJssel, Geertruidenberg and Meeden as part of this contract.

Increasing capacity

The work will increase the capacity of the high-voltage grid in Limburg. The upgrade of the substation includes the construction of a new GIS installation and the laying of underground high-voltage cables. The existing substation in Maasbracht will remain operational during the upgrade, but will be demolished once the work is complete. The work will be carried out largely using emission-free equipment, which means that the project is in line with Heijmans' strategic pillar of Sustainability.

Heijmans won this implementation assignment after submitting a design developed by a construction team, aimed at joint control of predictability. The station in Maasbracht has been in use since the 1960s. It closes the national 380 kV ring between Eindhoven and Dodewaard, which means this substation plays an important role in the national high-voltage grid. It also connects to the Limburg 150 kV grid, making 'Maasbracht' the meter box of Limburg. It is also an important hub in the European high-voltage grid, with connections to Belgium and Germany. The generators at the nearby Claus power station are also connected to this station.

Energy in the Netherlands

The Netherlands needs to expand its high-voltage grid because the demand for electricity is increasing sharply as a result of various sustainability measures. Consumers and businesses are also generating more and more of their own electricity, which is fed back into the grid. This assignment is fully in line with Heijmans' strategy for the period to 2030. Heijmans wants to play a more prominent role in the realisation of solutions for the complex challenges facing our country. These challenges are particularly wide-ranging, far-reaching and, due to their interconnection, quite complex in the areas of housing, accessibility, labour shortages, energy transition and climate.

About Heijmans

Royal Heijmans (AEX:HEIJM.NL) is a leading Dutch listed construction company with activities in Living, Working and Connecting: from project development, construction, technical services to infrastructure. Jan Heijmans started the company in 1923 as a paving contractor. In the intervening hundred years, Heijmans has grown into an area developer, technical service provider and construction company with more than 5,000 employees. They ensure that people can enjoy living, working and connecting. Every single day, Heijmans works on complex construction projects and social challenges that have an impact on the future of the Netherlands. As a sustainable leader, Heijmans is taking a step forward on this front by dedicating itself to the creation of a healthy living environment. Where people have a nice live and animals and nature are taking into account.

For further information/not for publication:

Press Martijn van de Koolwijk Spokesman +31 (0)6 41 25 55 08 mkoolwijk@heijmans.nl

Analysts

Bart Boleij Investor Relations +31 (0)6 53 12 25 61 bboleij@heijmans.nl