Resumo:
In January 2020, the National Power System Operator started using the DESSEM program. It is a
model developed by CEPEL and aims to determine the daily energy dispatch for the operation of
hydrothermal systems, including intermittent sources, with discretization of up to half an hour. This
model works in coordination with the DECOMP and NEWAVE models, which are medium and
long-term models for determining the dispatch and the hourly energy price for the following day.
This work presents a brief history of the Brazilian electricity sector, the way in which the country's
electro-energy operation is managed and the old and current model of daily energy dispatch are
explained, in addition to the methodology of operation of the post-DESSEM and its repercussions.
The objective is to understand and evaluate the interactions between the agents and the ONS with
the use of DESSEM as a very short-term model and the deviations observed between the model
generation proposals and those that are finalized in the programming stage. The work focuses on
the most important plants of the Furnas system, used as a case study. In addition, in order to
highlight the difference between the operating policies adopted by the model and those by the ONS,
a quantitative analysis was proposed in this work, with the purpose of identifying a possible
seasonal variation in order to gain greater sensitivity on the results of the energy operation.
