Serra da Mesa Plant


Credit: AC Júnior


The Serra da Mesa Hydroelectric Power Plant, located in the Alto Tocantins Basin in Goiás, is very important for the Brazilian energy industry. After its three generator units began producing a total output of 1,275 MW, the plant became a critical component, supplying electrical power to the South/Southeast/Center-West Interconnected System. It is also responsible for connecting this system and the North/Northeast system, acting as the link for North-South Interconnection.

Its dam is located in city of Minaçu (GO), along the main course of the Tocantins River, 1,790 km from its mouth. The Serra da Mesa reservoir has the largest water volume in Brazil, with 54.4 billion m³ over an area of 1,784 km².

The plant adds substantial energy gains to the interconnected system (6,300 GW/year), at a very competitive generating cost. The dam helps regulate the river and directly benefits other plants located downstream, especially the Tucuruí Hydroelectric Plant in Pará.

The Serra da Mesa operation represents a permanent solution serving the state of Goiás and the Federal District.

The project represents a new stage for two basic aspects of the Brazilian Electricity Sector. The first is automation. FURNAS has complete digital control of this underground power plant, supporting a coordinated power generation process combined with a diversified transmission system.

The other differential is the fact that this project is the result of private-sector partnership. In 1993, the Federal Government began a program that brought together a state-owned company and the private sector, using studies carried out by the DNAEE (National Department of Water and Electric Energy) and Eletrobras, Serra da Mesa Energia S.A. won the Partner Selection Process. The company was responsible for completing the plant, receiving 51.54% of the energy produced by the Serra da Mesa Plant in return.

FURNAS was responsible for managing construction and operating the plant due to its extensive experience with large-scale projects.

FURNAS has always focused on nature and ecology. The Serra da Mesa, Corumbá and Manso Plants are clear examples of this. The Company has agreements with environmental agencies (Goiás Environmental Foundation - Femago - and the Brazilian Environmental and Renewable Natural Resources Institute - Ibama), through 17 programs involving Wildlife Conservation, Indigenous Issue Management and Fish Monitoring, among other issues.


Technical Data


Dam

  • Type: riprap with clay core
  • Maximum height: 154 m
  • Total volume: 12,057,558 m³


Reservoir

  • Normal operating level: 460 m
  • Maximum flood level: 461.5 m
  • Level of expropriation: 460.5 m
  • Minimum operating level: 417.3 m
  • Flooded area: (460 m elevation) 1,784 km²
  • Total volume: 54.4 billion m³
  • Usable volume: 43.25 km³


Water Intake

  • Sliding gates
  • Quantity: 3
  • Water height on sill: 61.18 m
  • Width: 7.65 m
  • Height: 9.13 m
  • Manufacturer: BSI


Spillway

  • Maximum Discharge: 15 thousand m³/s
  • Segmented-style gates
  • Quantity: 5
  • Width: 15 m
  • Height: 20.4 m
  • Radius: 19 m
  • Manufacturer: BSI


Powerhouse

  • Type: subterranean
  • Width: 29.2 m
  • Length: 137 m
  • Maximum height: 69.8 m
  • Generator units: 3
  • Rotation: 120 RPM
  • Rated capacity: 1,275 MW


Turbines

  • Type: Francis vertical axis
  • Upper rotor diameter: 5,847.8 mm
  • Lower rotor diameter: 6,460.82 mm
  • Manufacturer: SADE


Generators

  • Frequency: 60 Hz
  • Terminal voltage: 15 kV
  • Manufacturer: ABB
  • Transformers: 10 (operation + back-up)
  • Type: single-phase
  • Total operating capacity: 1,418.40 MVA
  • Transformation ratio: 15 / 500 kV
  • Manufacturer: ABB