eSett is responsible for the Nordic imbalance settlement, including Norway. They provide an open data portal where you can find information about imbalance settlement data and market participant structures. Visit eSett's open data portal for detailed and real-time data on imbalance prices​ (eSett)​.

Statnett is a member of the European Network of Transmission System Operators for Electricity (ENTSO-E).

https://opendata.esett.com/prices_single

A good reference: https://www.statnett.no/globalassets/for-aktorer-i-kraftsystemet/marked/reservemarkeder/nordic-wind-and-solar-publication-.pdf