NOVELTY - This invention relates to facility and method that use variation of water surface level and water floating power to generate electrical power and the principles are using a large number of large-sized floating tanks, which float up and down with the variation of water surface level, to gain a strong vertically-elevating kinetic energy, and a linkage feeds the linear kinetic energy to a kinetic energy conversion device for conversion into high-speed rotational kinetic energy. The high-speed rotational kinetic energy is then used to drive a generator to generate electricity. This invention is applicable in sites where noticeable variation of water surface level occurs, such as oceans, reservoirs, lakes and rivers, and is suitable to most terrains and weathers. The kinetic energy conversion device can be of two types, namely a gear type and a hydraulic type. The operation principle of the gear type kinetic energy conversion device is using a direction-changing device that is made up of a rack and a pinion to convert the fed linear kinetic energy into rotational kinetic energy. The rotational kinetic energy, which is of extremely low speeds, is then fed by a coupler to a speed-up device that is made up of multiple gear sets in which gears drive pinions to be converted into high-speed rotational kinetic energy. The high-speed rotational kinetic energy is then applied to a generator for electricity generation. The operation principle of the hydraulic type kinetic energy conversion device is using the fed linear kinetic energy to drive an elevator inside the hydraulic type kinetic energy conversion device. On the elevator, a plurality of liquid compression constructed like super-sized hydraulic cylinders are mounted and upper ends of all liquid compression tanks are fixed to a support structure of a workshop. When the elevator inside the hydraulic type kinetic energy conversion device is subjected to a force to elevate or lower, the liquid inside the liquid compression tanks are compressed to a hydraulic motor to generate high-speed rotational kinetic energy. The high-speed rotational kinetic energy is then applied to a generator for electricity generation.