EPE's short and medium term planning is embodied in the Ten-Year Energy Expansion Plan (PDE). The PDE is a yearly released publication that indicates the energy expansion in the ten-year horizon, according to the Government's perspectives. Based on consistent criteria and the regulatory framework, the expansion strategy is analyzed according to an integrated view for all relevant energy sources. Taking into account the synergies with other economic sectors, the PDE analyses aims at generating better production reliability levels, lower production costs, and the mitigation of environment impacts. All these outcomes are scrutinized through a Public Consultation in which MME receives contributions from different stakeholders (civil society, government agencies, companies and other institutions) in order to reinforce the consistency of the country's growth perspectives and the required energy supply expansion in order to ensure its reliability at affordable costs, and environmentally sustainable way. In the PDE, it is possible to find analysis and information on: the energy security of the system; balance of electricitity and energy supply and demand; the indicative power generation expansion; availability of fuels; environmental analyses, etc. This is a fundamental instrument for explaining the costs and benefits of public policies and measures.
The PDE also defines the priority set of transmission facilities to be considered by MME to participate in transmission power auctions. Further feasibility and detailed studies are conducted in the "R1" reports (technical and economic feasibility studies) that later are included in the Transmission Expansion Plan (PET). It is up to the ONS, in the Expansion and Reinforcement Plan (PAR), to propose further adjustments on the suggested transmission facilities, based on specificities of the operation of the system.
In relation to electricity studies, two aspects must be highlighted: first, there is an interaction between the generation and transmission studies that is considered in the cost-benefit analysis of the capacity increase of the regional grid connections, as well as social and environmental impact studies of generation and transmission alternatives. Second, due to the predominance of the hydraulic source in our generating system, operation decisions affect the future behavior of the power system and vice-versa. Planning the System Operation is the sole responsibility of ONS, under ANEEL regulation and supervision. Although the responsibilities of each institution are well defined, expansion and operation planning activities are complementary. Thus, in the horizon up to five years there is an interface between ONS and EPE in the load forecasting process. As a result, strenghtening instituional relationship between ONS and EPE is essential for better studies and operation policies, as well as exchange on data, information and computational models.