during the flow into the turbine and about 20 during the flow out of the turbine this cross flow function is the reason why a banki turbine is particularly suitable downstream of the turbine 14 there is a second guide plate 17 which has a reversed curvature in relation to the first guide plate 16 to guide a further amount of water into the turbine 14 the rotation of the turbine 14 which is caused by the water will be transferred by its axis 14 a to a transmission not shown coupled to an electric generator for producing electric energy a transmission is favorable in most applications to transform the rotational speed of the turbine 14 to a rotational speed which is optimal for the generator 11 it is evident that different kinds of generators may be used e g alternator or continuous current generator depending on the circumstances in the preferred embodiment the electrical power which is produced by the generator 11 is supplied to the stock pumps not shown which feed the headbox 2 in accordance with the invention large amounts of energy may be recovered with an optimized arrangement the total yield may be about 60 if the stock flow is about 0 5 m 3 sec per cross sectional meter the power that can be recovered for a six meter wide machine is about 810 kw at a price of 0 30 sek kw this will lead to annual saving of about 2 msek with 350 days of operation per year considering further aspects of the invention e.