It is constructing Alto Tamega Hydroelectric Complex in Portugal to facilitate renewable energy from hydropower. With its 4 large reservoirs and a total installed capacity of 1200MW and an annual energy production of 2000GWh. Detailed hydraulic investigations are going to be carried out at Graz University of Technology to guarantee the unrestricted operability of the high head power plant. Especially the storage of electricity and grid stabilization need pumped storage schemes. At the Institute of Hydraulic Engineering and Water Resources Management numerical calculations together with a hydraulic model test of the tailwater system with a large surge tank (scale 1:25) are set up to allow the stable operation of the hydro power plant. The investigations are planned to be finalized during the year 2017 and will provide excellent opportunities for students’ research with highest practical relevance.