IDA (Intraday Auction)
An Intraday Auction is a coupled auction inside SIDC that prices intraday cross-border capacity. Continuous intraday trading allocates capacity first come, first served; IDAs add scheduled auctions where scarce intraday capacity receives a transparent price signal. The European IDA solution went live in June 2024.
An Intraday Auction (IDA) is a coupled auction inside SIDC that prices intraday cross-border capacity. Continuous intraday trading allocates capacity first come, first served; IDAs add scheduled auctions where scarce intraday capacity receives an explicit price signal. The European IDA solution went live in June 2024 across most coupled countries, including Estonia.
Why IDAs were added
Before IDAs, intraday cross-border capacity in SIDC continuous trading had no scarcity price of its own. If capacity existed, the first compatible order could use it. IDAs harmonise how capacity is calculated and allocated in the intraday timeframe and create a transparent price for shortage at defined moments. This improves incentives for traders deciding whether to use capacity now or wait.
Products and order types
The SIDC IDA design supports hourly, half-hourly and quarter-hourly products, with simple orders and selected block or merit-order types depending on NEMO implementation. In practice, the important point for Estonia is that IDAs sit between day-ahead settlement and continuous intraday trading: they are another tool for adjusting positions before physical delivery.
Sources
ENTSO-E: Intraday Auctions on SIDC · ACER: CACM implementation monitoring