Construction Update Q4 2025 

NRG PALLAS marked an important milestone of the execution phase by celebrating the start of the PALLAS-reactor’s construction together with local and international partners on 29th of September. Anita van den Ende, Secretary-General of the Ministry of Health, Welfare and Sport, gave the symbolical go-ahead for the start of the reactor’s construction. The works have steadily continued on the current main areas of the construction site: the preparatory works for the construction of the PALLAS-reactor building and the works on the pit of the Secondary cooling system building.    

Reactor Building: Preparatory Works 

Following the initial works in the construction pit – protective membrane installation and the pouring of an 8-cm concrete layer -  the activities for the construction of the PALLAS-reactor building have progressed further over past period. All three tower cranes are now installed to support lifting heavy materials and equipment to and from the construction pit. The first and third cranes each reach 35 metres in height with a working radius of 74 metres, while the second crane stands 23 metres high with a 40-metre working radius. 

To prepare for the construction of the first underground floor, approximately 350 tonnes of reinforcement steel have been delivered to the site. In December, work begins on installing the one-metre-high bearing slab at the bottom of the construction pit. Once completed, the first underground concrete floor—divided into five sections—will be poured across the whole building area, measuring roughly 42.5 by 45.5 metres.

Secondary Cooling System: Construction pit works  

The secondary cooling system building is part of the PALLLAS-reactor secondary cooling system. This isolated system contributes to cooling the reactor by circulating water extracted from the Noordhollandsch Kanaal (inlet of the pipelines) and disposed to the North Sea (outlet of the pipelines). To allow for the construction of the building, the construction pit is being realized in the first step. 

With the pit’s perimeter previously established, works continue with the excavation of the pit. The pit was fist excavated in a dry way to +1 NAP. Afterwards, the bracing frame –designed to ensure the structural stability of the pit and preventing its walls from collapsing, was installed. The excavation progressed further in dry conditions to -2 NAP and continues in the dry way to a depth of -9.8 NAP.