One of the most complex initiatives currently working its way through the PJM stakeholder process is the consideration for a new combined cycle modeling tool.
The Modeling Generation Senior Task Force meets monthly to tackle the intricacies of developing the tool. The task force’s focus is expansion of the model used by PJM in order to improve the ability to represent the flexible operation of various components of all generation, not just combined cycle units.
Stakeholders are immersed in how much flexibility the models can bear – looking at aspects from the charter, modeling capabilities of the units, rules for day-ahead and real-time markets and “ideal versus practical.” At its Nov. 17 meeting, for example, stakeholders reviewed a matrix, discussing options for switching, firm and non-firm fuel transport.
These models are necessary to support reliability analyses of the transmission system. PJM develops data requirements, reporting procedures and schedules for the transmission owners, generation owners and other stakeholders.
Task force Chair Stan Williams, director – Settlements and Operations Analysis, said the task force builds on previous work from a member group of combined cycle owners, which discussed the design and operation of combined cycle units and their integration into the market and real‐time operations of PJM.
That group concluded that a more detailed model for combined cycle units might be equally applicable to other steam units. In addition, the Operating Committee completed a practical amount of work in 2014, including the development of an options matrix.
Williams said, now that the stakeholders have reviewed the matrix several times, PJM staff can begin discussions about what PJM is capable of doing from the technological standpoint.
Individual units within the combined cycle group can have individual physical components modeled and have individual unit constraints. That means each combustion turbine and each steam turbine within the combined cycle group can have its own start‐up cost, minimum run time, minimum down time, offer curves, etc.
Troy Cawley, senior engineer – Real-Time Market Operations, has developed educational materials for generating operating parameters that provide stakeholders with a general idea of what flexible generation market models might look like going forward. his includes multiple configuration diagrams. For the December meeting, PJM will provide additional diagrams detailing the transitions of generating resources between configurations and the cost-recovery mechanisms used for these transitions.
Williams added that having additional generators participate in the task force would help discussions on implementation options.
Eventually, the task force will develop a single solution package to take to the Markets & Reliability Committee for a vote.