Why is hydroelectric power more efficient than the use of coal or uranium?

Answer 1

Hydroelectric power is 100% efficient as there is no energy requirement to draw/start power production (outside of that to construct the materials of course).

To start coal or uranium energy processes energy is required to start the process. These processes rely on heat from these energy sources to create steam which can run turbines which naturally lose energy released from these sources. Because not all of this energy is released in the form of thermal energy and because converting energy is intrinsically inefficient, these sources of power are currently less energy efficient.

(actually hydroelectric plants are no more efficient than any other turbines, and possibly less than most highly efficient multi- stage compound condensing steam turbines. The efficiency is based upon how much of the energy passing through the turbine is converted to mechanical energy. Roughly 60% for the best designs.)

Hydroelectric power has high start up costs, dam building [habitat flooding], and can only be built in specific areas (river valleys) as they take up vast quantities of space.

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