ISC Consulting Engineers A/S: Natural Ventilation in Offshore Substations

Offshore Substation

IESVE used to perform dynamic simulations of natural ventilation to dramatically reduce heat loads in transformer and machinery rooms in order to meet temperature targets.

Key Facts

  • Temperature Requirements fully met
  • Weather Data site specific
  • VE Integration compatible with DSM and CFD calculations
  • Clear visualisation helpful for client


ISC carried out detailed design on the Northwind substation topside, which is placed in the Belgian North Sea. The substation has a capacity of 216 MW and weighs 1200 tonnes. The substation was installed in 2013. The 14 km2 wind farm comprises 72 wind turbines of each 3 MW is placed 37 km from shore.

Natural ventilation calculations have been undertaken for a transformer room with total heat load of 70 kW and a reactor room with total heat load of 19.4 kW. With the help of IESVE the necessary opening size has been calculated in order to meet the temperature requirements.

Innogy Nordsee Ost

ISC has carried out detailed design of the topside on the Nordsee Ost substation. The topside is placed on a traditional 4 legged jacket in 23 m water approximately 51 km off the German coast. The substation has a capacity of 295.2 MW. The topside weighs 1600 tonnes. The wind farm comprises an area of 36 km2 with 48 6.15 MW turbines. The substation was scheduled to be installed in 2014.

The topside is a classic design with 2 transformers and a helideck. Each transformer room has a heat load of 80 kW. Using the IESVE CFD module it was possible to document, that not only general temperature requirements in the room were met, but also temperature requirements at a particular height.

Gode Wind 01 and 02

ISC carried out detailed design on the Gode Wind I and II substations. The substations have a capacity of respectively 332 MW and 252 MW. The Gode Wind I wind farm comprises an area of 66 km2 with 546 MW turbines and the Gode Wind II wind farm comprises 66 km2 with 846 MW turbines. Both substations were scheduled to be installed in 2014.

Each of the topsides has 2 transformers and a helideck. Using the IESVE, calculations of natural ventilation were carried out for the transformer room and the machinery room, located besides on the mezzanine deck, with the total heat load of 36.5 kW. The design of openings on the façade as well as openings on the rooftop was optimized. The scientifically accurate climate data for the actual location has been validated with the actual measurements near the station. All the temperature requirements have been met, including the monthly average of the hottest month below 30 ⁰C.

“IESVE has several advantages for this purpose in comparison to other simulation software. It has the flexibility to import weather data from worldwide weather data providers, which is important, when it comes to a specific location of the substation in the middle of the sea. When performing dynamic simulations of natural ventilation, these are based on both the thermal and wind pressure thrust. Compatibility with CFD module makes it easy and fast to build up a CFD calculation in order to explore the temperatures in the space and on the surfaces. Finally, the good visualization of results makes it easier to communicate to the client.”

ISC Consulting Engineers A/S