AAC Clyde Space Wins EUR 76.3 M Order for Microwave Radiometer Instruments for EPS-Sterna Weather Satellites

AAC Clyde Space has received an order from OHB Sweden AB to deliver 20 microwave radiometers, the core weather instrument for the EPS-Sterna satellite programme. The order value is EUR 76.3 million (approx. SEK 820 M).

Work on the programme will start immediately. Revenue from the project is recognized using the percentage-of-completion method based on costs incurred in the project. As a significant portion of project activities takes place during the early phases of the programme, approximately half of the contract value is expected to be recognised by the time the first six instruments are delivered by the end of 2028. Thereafter, the remaining instruments are expected to be delivered at a rate of two instruments per year until 2035.

The microwave radiometer is the mission-critical instrument onboard each weather satellite. It measures temperature and humidity throughout the atmosphere, data that is essential for modern numerical weather prediction. The instrument is developed and built by AAC Omnisys, the Gothenburg-based subsidiary of AAC Clyde Space. Its technology has been validated in the Arctic Weather Satellite and enables a new generation of smaller, more capable and more cost-efficient weather satellites.

“We are extremely proud of this programme and thank OHB, ESA and EUMETSAT for entrusting us with the supply of the critical payload for this next generation weather mission,” says Luis Gomes, CEO of AAC Clyde Space. “These instruments will improve global weather forecasts, while significantly reducing the cost of weather missions. It is a perfect example of how we connect space technology with benefits that make a difference in our daily lives.”

The EPS-Sterna satellites are built by OHB Sweden as prime contractor under a programme led by the European Space Agency (ESA) on behalf of the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT).

“EPS-Sterna is an important programme for European weather forecasting, and a strong example of Swedish space capabilities,” says Fredrik Sjöberg, Managing Director of OHB Sweden. “Together with AAC Clyde Space we demonstrated this technology in record time and at significantly lower cost. We have a long history of collaboration and look forward to continuing this partnership.”

EPS-Sterna

EPS-Sterna is Europe's next-generation operational weather satellite system providing frequent atmospheric temperature and humidity sounding data for numerical weather prediction. The constellation will consist of six satellites operating simultaneously in polar orbit, with replacement satellites launched over time to maintain continuous observations. The first satellite is expected to launch in 2029. In total, 20 satellites will be deployed during the programme's operational lifetime, which extends to 2042.

Extreme weather events have caused more than EUR 600 billion in economic losses in Europe since 1980 and contributed to an estimated 166,000 fatalities. Weather services supported by satellite observations generate at least EUR 52.8 billion in economic benefits annually across EUMETSAT Member States.

Impact studies indicate that EPS-Sterna observations will reduce forecast errors in numerical weather prediction by around 6% across EUMETSAT Member States and up to 9% in the Arctic region.

The mission builds on the technology demonstrated by Arctic Weather Satellite.

The Microwave Radiometer

Microwave radiometers measure natural thermal radiation from the Earth and atmosphere at specific microwave frequencies. These measurements allow scientists to determine atmospheric temperature and humidity profiles through clouds, rain and snow, providing essential input to modern numerical weather prediction models.

The radiometer developed by AAC Omnisys combines high sensitivity with a compact design, making it possible to deploy advanced weather sensing capabilities on smaller and more cost-efficient satellites. The instrument includes multiple microwave channels, including the 325 GHz band, enabling observations of atmospheric moisture and ice formation inside clouds that are difficult to capture with other satellite instruments.

The instrument builds on microwave technology developed in collaboration with Chalmers University of Technology and has been successfully demonstrated in orbit on the Arctic Weather Satellite, whose data are already used in operational weather forecasting.