The basic model of bid-based, security-constrained, economic dispatch with locational prices is well understood and provides the foundation for efficient pricing. The most common analysis is for a single period with well-behaved bids and offers without uncertainty. With independent dispatches, serial application of this approach produces efficient prices. The real dispatch system requires some degree of look-ahead with intertemporal constraints. The expansion of intermittent resources increases the importance of efficient multi-period pricing. In principle, the same model applies for the multi-period dispatch. Relaxing any of the assumptions, however, presents new challenges for efficient pricing. Rolling dispatches must adjust to uncertain conditions inducing changes over time. Bids and offers with start-up, shut-down, and multi-period operating constraints require some form of extended locational marginal pricing and associated uplift requirements. Current practices differ across organized market. How important are efficient multi-period prices? What approaches might balance the current competing requirements to deal with efficiency, uncertainty and computational feasibility? What new modeling and software innovations are on the horizon?
