If demand ends up being greater than forecast, or there is unforeseen generation unavailability, extra sources of power may be needed to manage the system. One form of reserve that is used to manage this is Short Term Operating Reserve (STOR), which runs from 20 mins - 4 hours after a frequency event occurs. These market information reports are produced after each tender round and are designed to give existing and potential STOR participants an overall view of the tenders received. They give data on the tendered utilisation and availability prices, our forward contracted position and further details on the type and dynamics of the tendered units. **Please Note:** This datafeed **is no longer being updated** as we are not currently procuring STOR. More information about the future of STOR tenders can be found here: [https://www.nationalgrideso.com/balancing-services/reserve-services/short-term-operating-reserve-stor](https://www.nationalgrideso.com/balancing-services/reserve-services/short-term-operating-reserve-stor)