Access documents related to the Subhourly Real-Time Settlement project.
The ISO is evaluating a move to a subhourly settlement interval for generation resources, external transactions, dispatchable asset-related demand resources, and demand-response resources in the real-time markets.
The real-time markets (energy, reserve, and regulation) are settled hourly, even though the ISO calculates real-time locational marginal prices (LMPs) every five minutes. Existing settlement rules tend to undercompensate certain resources, particularly more flexible generation and storage assets that respond quickly when system events result in tight operating conditions and there are significant midhour price changes. Compensating resources at the more granular, five-minute price would help improve price formation by ensuring that the price suppliers are paid for real-time performance is a more accurate market signal of the power system’s current operating conditions. In the future, this change may also provide an additional revenue source for wholesale electricity storage resources.
Training materials related to the project are available on the Training Materials webpage.
The Subhourly Real-Time Settlement project is just one of several key projects at the ISO, which continuously undertakes a variety of short- and long-term projects to enhance the region's competitive wholesale electricity markets and ensure reliable operation of the power grid.