Abstract: Float/weights are positioned in the tidal water, arranged to rise and fall with the tides. A power unit including a cylinder and piston is arranged with the piston connected with the float/weights, and draws water into it upon the float/weights rising and forcing it into a storage unit upon the float/weights dropping. The storage unit includes a cylinder and a weighted piston. After the storage unit is filled, the water is let out to drive a water turbine and generator. The apparatus may use a closed circuit for the water, or an open circuit and draw it directly from the sea and return it to the sea. In the use of a closed circuit, instead of sea water, the apparatus may use fresh water, or oil. The apparatus is also adapted to use compressed gas instead of liquid.