Discharge measurements at SLAPY HPP – Comparison between acoustic scintillation and pressure-time methods

Slapy hydroelectric plant (HPP) is a typical mid-head HPP hosting three 50 MW Kaplan turbines on the Vltava river, 50 km south of Prague, Czech Republic. The gross head is 47 ÷ 53 m in normal operation regime. Pressure-time (PT) flow measurement method was specified for the acceptance tests of the upgraded Unit #3 in autumn 2011 and OSC had the contract for those tests. ASL AQFlow proposed to both OSC and EDF to use the Slapy HPP efficiency measurements on the Unit #3 for an on-site comparison test between the PT and Acoustic Scintillation (AS) methods. Both OSC. and EDF agreed and the comparison testing proceeded thanks to the kind permission of ČEZ Hydro Power Plants management. OSC supported the design and manufacture of the movable frame for the AS method, while EDF provided its own AS system as well as the necessary workforce.