Porto Colômbia Plant


Credit: AC Júnior


Low head hydroelectric plants are rare in Brazil and Porto Colombia is the only facility of this type in the FURNAS System. Since construction of the Porto Colombia Plant began in March 1970, it has set many new records, especially in achieving its construction deadlines.

Located in the Grande River, between the cities of Planura (MG) and Guaíra (SP), the Plant was built to take advantage of the high level of discharge regulation provided by the Furnas Plant reservoir. The Porto Colombia dam forms a 143 km² lake, which became another major asset helping regulate the Grande River flow.

The Plant began operating in June 1973 and, by January 1974, it had already reached its total installed capacity of 320 MW (4 X 80 MW)


Technical Data


Dam

  • Type: clay, homogeneous segment
  • Maximum height: 40 m
  • Development at the crown: 1652 m
  • Width at crown: 10 m
  • Elevation at crown: 469.7 m
  • Total volume: 2,736,497 m³


Reservoir

  • Normal operating level: 467.2 m
  • Maximum flood level: 467.2 m
  • Level of expropriation: 467.5 m
  • Minimum operating level: 465.5 m
  • Flooded area: 143 km²
  • Total volume: 1.525 billion m³
  • Usable volume: 2.335 billion m³


Water transition and intake walls

  • Type: gravity
  • Development at the crown: 184 m
  • Elevation at crown: 469.7 m
  • Total volume: 88,011 m³


Spillway

  • Maximum Discharge: 16 thousand m³/s
  • Segmented gates
  • Quantity: 9
  • Width: 15 m
  • Height: 15.4 m
  • Radius: 15 m
  • Manufacturer: ATB (Italy and Brazil)


Powerhouse

  • Type: sheltered
  • Size: 170 m x 17 m
  • Generator units: 4
  • Rotation: 85.7 RPM
  • Rated capacity: 80 MW


Turbines

  • Type: Kaplan
  • Rotor diameter: 7.7 m
  • Manufacturers: Nohab/Sweden and Bardella/Brazil


Generators

  • Frequency: 60 Hz
  • Terminal voltage: 13.8 kV
  • Manufacturer: Asea/Sweden
  • Transformers: 5 (operation + back-up)
  • Type: three-phase
  • Total operating capacity: 336 MVA
  • Transformation ratio: 13.8/138 kV
  • Manufacturer: ABB