Aneel is considering integrating special treatment for reserve energy plants into the new curtailment guidelines, proposing to test the mechanism during the sector’s shadow operation phase.
The National Electric Energy Agency (Aneel) is set to resume voting this Tuesday on new rules for curtailment—the reduction or limitation of power generation. The debate, which has been ongoing since June, has gained a new strategic component: the possibility of applying a unique accounting treatment for wind and solar plants linked to reserve energy contracts.
The proposal, developed by the agency’s technical staff at the request of director Gentil Nogueira, suggests that when calculating curtailment for energy-related reasons, priority should be given to projects that do not have reserve energy contracts. In this scenario, plants contracted under this specific modality would only be impacted in accounting terms if the volume of curtailment exceeded the capacity of other plants.
The role of reserve energy in the system
It is important to emphasize that this measure does not alter the autonomy of the National Electric System Operator (ONS). The operator retains the authority to physically reduce generation as needed to ensure the security of the National Interconnected System (SIN). The change proposed by the Superintendency for the Regulation of Generation Services and the Energy Market (SGM) is strictly related to accounting.
Regarding this, the SGM clarified the rationale behind the suggestion:
The role of reserve energy in planning, which is focused on supply security, allows for evaluating different treatment in this allocation without altering the physical curtailment capability of the plants.
Tests and deadlines in Public Consultation 45
The inclusion of this analysis in Public Consultation 45/2019 comes at a decisive moment. Since the proposal regarding reserve energy reached director Gentil Nogueira‘s office just before the final vote, the technical recommendation is that the model be validated first during a “shadow period.” This phase would function as a testing environment without immediate financial impacts, allowing the agency to evaluate the rule’s effectiveness before its final implementation.
In addition to the new allocation criteria, the Aneel board continues to debate the transition schedule. The deadline for starting the shadow operation is still under dispute: while rapporteur Agnes da Costa and former director Fernando Mosna suggested 90 days after the rule’s publication, the ONS has requested an extension to 180 days. The operator argues that the test period requires complex adjustments to operational systems and new monitoring routines to ensure the stability of the country’s renewable generation fleet.
