Galleto hydroelectric power station


Plant characteristics

The Galletto Monte Sant’Angelo plant is the main hydroelectric power plant of the Nera-Velino rivers system, located on the left bank of the Nera river in Papigno, in the province of Terni, just downstream of the Marmore waterfalls.

The plant includes the Galletto section, built in the years 1926-1929 and the Monte S. Angelo section, which constitutes its expansion, which entered into service in the years 1971-1973; the two sections are fed by the waters of the daily regulation basin of Piediluco where the waters of the Velino river and those of the derivation of the Medio Nera which flows the waters of the Alto Nera enter.

The Galleto power plant, powered by a 318 m long forced pipe which departs from the West piezometric well, has four vertical axis groups, consisting of Francis turbines with vertical axis, coupled with synchronous generators of 50 MVA each.

centrale idroelettrica galleto


W.E.S.T. Hydro (Water Energy Systems & Tests S.r.l.) was commissioned by Endesa S.p.A., now E-On S.p.A, to carry out specialist tests to determine the hydraulic performance of the group, after replacing the electro-hydraulic machinery.

The performance measurements were performed using the thermodynamic method; therefore all tests were carried out in accordance with IEC EN60041-Ed 11-1991 and subsequent updates.

Turbine characteristic

Manufacturer: ANDRITZ_VATECH – Schio – Italy

Turbine type: N. 4 – Francis with vertical axis

Nominal data

  • Net head: 197 m
  • Flow: 22.50 m3 / s
  • Power output: 40.532 MW


  • Customer: E.On S.p.A. – Rome
  • Contract no. : 6000002365 of 25.01.2008
  • Total amount: € 1,594,500
  • Execution year: 2009