JRC Workshop 'Addressing flexibility in energy system models edition:1 location:Petten, The Netherlands date:4-5 December 2014
To limit the computational cost, long-term energy system planning models (e.g., MARKAL/TIMES) traditionally operate at a low temporal resolution and disregard detailed techno-economic operational constraints of the power system and individual power plants. Both model simplifications are shown to have a significant impact on the model results when analyzing systems with high shares of intermittent renewables For this reason, different attempts have been made to bridge the gap between planning and operational models, both in terms of the temporal resolution and the level of techno-economic detail. With respect to increasing the level of techno-economic detail in system planning models, distinct approaches either aim to soft-link the planning model to a detailed operational model, or to directly increase the level of techno-economic operational detail in the planning model by introducing additional constraints and variables. Due to computational limits, the additional constraints directly integrated in planning models are often very stylized. As such, these stylized constraints do not directly represent the physical processes, but rather aim to mimic the impact of these physical constraints on the generation scheduling. Moreover, these stylized representations of operational constraints are rarely verified. A thorough understanding of the electricity system and underlying processes is needed to calibrate these constraints to the specific energy system that is being studied and care is needed transferring these constraints to models for different energy systems. In this regard, the aim of this work is to obtain and verify a less stylized, robust set of operational constraints for integration in planning models, taking into account computational restrictions. To this end, a clustered unit commitment model in which different constraints can easily be turned on or off, is used.