It is incorrect to consider tidal power as renewable energy. Harnessing tidal energy will pose more severe problems than using fossil fuels. This study provides quantitative estimates to show how using tidal energy can destroy the environment in a short amount of time. Tides are induced by the rotation of the Earth with respect to the gravity of the Moon and Sun. The rotational energy of the Earth is naturally dissipated by tides slowly. Consuming tidal energy further reduces the rotational energy, accelerates the energy loss rate, and decelerates the rotation of the Earth. Based on the average pace of world energy consumption over the last 50 years, if we were to extract the rotational energy just to supply 1% of the world's energy consumption, the rotation of the Earth would lock to the Moon in about 1000 years. As a consequence, one side of the Earth would be exposed to the Sun for a much longer period of time than it is today. The temperature would rise extremely high on that side and drop extremely low on the other side. The environment would become intolerable, and most life on Earth could be wiped out.

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