Apparatus for the production of renewable energy including: - a tank configured to be immersed in a free-flowing stream and comprising two side walls and a bottom wall which delimit an area for the passage of water in the tank, - at least three blades, each blade 20 having dimensions such as to close the passage area of the water in the tank and comprising a bottom side configured to operate in contact with said bottom wall during a thrust phase in which the water exerts pressure on the blade by moving it, an upper side and two sides configured to operate in contact with said side walls during the thrust phase of the water on the blade, - guide means of the upper side of the blade arranged in correspondence with the upper part of the tank and configured to guide the upper side during the thrust phase of the water on the blade so as to keep the blade in a transverse position to the water flow in the tank, - lower guide means arranged in correspondence with the lower part of the tank and configured to guide the bottom side of the blade during a first recovery phase of the blade in which the side top of the blade is not guided by the guide means, - upper guide means arranged in correspondence with the upper part of the tank and configured to guide the bottom side of the blade during a second recovery phase of the blade, in which the upper side of the blade is not guided by the guide means and the blade is free to float, so as to return it to the position in which the water exerts pressure on the blade to start the push phase, - motion transmission means rotatably connected to the bottom side of the blade and configured to transmit the motion from the blade which is pushed by the water pressure to the other blades which in the recovery phase are not pushed by the water pressure, - guide means configured to guide the motion transmission means connected to the blades from the position in which, in the thrust phase, the water exerts pressure on the blade to the position in which, in the recovery phase of the blade, the blade is free to float, to then return said motion transmission means to the starting position in which the water exerts pressure on the blade. - a tank configured to be immersed in a free-flowing stream and comprising two side walls and a bottom wall which delimit an area for the passage of water in the tank, - at least three blades, each blade 20 having dimensions such as to close the passage area of the water in the tank and comprising a bottom side configured to operate in contact with said bottom wall during a thrust phase in which the water exerts pressure on the blade by moving it, an upper side and two sides configured to operate in contact with said side walls during the thrust phase of the water on the blade, - guide means of the upper side of the blade arranged in correspondence with the upper part of the tank and configured to guide the upper side during the thrust phase of the water on the blade so as to keep the blade in a transverse position to the water flow in the tank, - lower guide means arranged in correspondence with the lower part of the tank and configured to guide the bottom side of the blade during a first recovery phase of the blade in which the side top of the blade is not guided by the guide means, - upper guide means arranged in correspondence with the upper part of the tank and configured to guide the bottom side of the blade during a second recovery phase of the blade, in which the upper side of the blade is not guided by the guide means and the blade is free to float, so as to return it to the position in which the water exerts pressure on the blade to start the push phase, - motion transmission means rotatably connected to the bottom side of the blade and configured to transmit the motion from the blade which is pushed by the water pressure to the other blades which in the recovery phase are not pushed by the water pressure, - guide means configured to guide the motion transmission means connected to the blades from the position in which, in the thrust phase, the water exerts pressure on the blade to the position in which, in the recovery phase of the blade, the blade is free to float, to then return said motion transmission means to the starting position in which the water exerts pressure on the blade.