With an increase of variable RES and the further electrification of the energy system, physical congestions caused by grid constraints will be more common. Redispatching is an alleviating action to reduce these constraints that can be performed by changing the dispatching from generators, through curtailment, or otherwise restricting injection or demand. Redispatching can be performed mainly in two ways:
- Regulated approach (or rule-based approach) in which the System Operator (SO) centrally plans and mandates any redispatching actions.
- Market-based approach in which the SO asks on a voluntary basis the market to adjust production or demand at either side of the congestion.
While the market-based approach is backed by the Electricity Market Regulation and Directive, concerns of inc-dec gaming and market power by participants has driven some countries, in particular Germany, towards a regulated approach.
The objective of this position paper is to address the concerns and benefits of a market-based approach, how the existing legislation covers the risks, and proposes mitigating measures and tools for National Regulatory Agencies and SO to fully overcome them.