Squeezing the hosting capacity: what is the value of active power curtailment?

The planning option of active power curtailment in electrical distribution grids intends to quickly integrate renewable energy sources into the grid, manage grid reinforcement and expansion, and prioritize planning measures. In Germany, a curtailment of 3 % of the annual production of photovoltaic plants and onshore wind power plants is allowed in the planning. Adequately representing these 3 % in grid planning is a challenge that has been addressed in several studies. There are a few caveats regarding the consideration of operational expenditures. On the one hand, the inconsistency between the “compliance with the 3 % criterion” in grid planning and operation makes it obsolete to derive the “real curtailed energy” (grid operation) within the planning process. On the other hand, there is a lack of dependable price assumptions for the reimbursement of the curtailed energy. In this paper, we show how different assumptions for the criterion compliance and the curtailment price change the economic effect of curtailment. To this end, we propose a framework for the assessment of criterion compliance and conduct a case study on a German MV grid model.