Trading period
A trading period (kauplemisperiood) is, per Elering's glossary, the time interval set out in the network code within which a market participant must maintain its balance. It is the basic time unit for imbalance settlement, day-ahead clearing and intraday matching. Estonia historically used a one-hour period; under EBGL Article 53 (Reg (EU) 2017/2195) the EU mandates 15-minute imbalance settlement, with SDAC moving to 15-minute MTU on 1 October 2025.
A trading period (kauplemisperiood) is, per Elering's glossary, the time interval set out in the network code within which a market participant is required to maintain its balance. It is the basic time unit for everything downstream, imbalance settlement, day-ahead clearing, intraday matching.
From hourly to 15 minutes
Estonia historically used a one-hour trading period, with the day starting at 00:00 and the last hour 23:00–00:00. Under EBGL Article 53 (Commission Regulation (EU) 2017/2195), the EU mandates a 15-minute imbalance-settlement period (ISP) across all Member States. Estonia has transitioned its imbalance settlement and balancing-market activations to 15-minute resolution; the SDAC day-ahead market moved to 15-minute MTU on 1 October 2025.
What the change does to economics
A finer trading period rewards faster assets. A battery that responds in seconds captures intra-quarter-hour spreads invisible at the hourly resolution. Slower assets, combined-cycle plants, heat pumps with thermal inertia, face larger relative imbalance penalties because their ramp rates are now in the same band as the settlement window. The transition has compounded the structural advantage of fast-flexibility assets.