Efficient balancing by effort-based activation of demand response services

We present a unified model for flexibility services in the power system, identify two existing categories (ramping and loading) and introduce a new category (stalling). Each service is characterised by duration, capacity and effort, with associated prices. We show that the effort of stalling, measurable in kWh2, is a significant cost component for balancing through storage and demand response (DR). In future energy systems - with increased reliance on renewable generation - storage and DR resources are expected to become an important component of power system flexibility and balancing. Existing resource allocation mechanisms are mainly based on pricing in kW (for ramping) and in kWh (for load). Simulations demonstrate that conventional pricing mechanisms yield inefficient allocations of storage and DR resources for power balancing. In contrast, we show that introducing an additional pricing component in e/kWh2 (for stalling) improves the allocation efficiency.