Question

What are the limitations of extracting energy from - (a) the wind? (b) Waves? (c) Tides?

Answer 1

The limitations of extracting energy from:

1. Wind: To produce power from wind energy, a windmill demands or required a wind speed of much more than $15\mathrm{km}/\mathrm{h}$, and a significant number of windmills are necessary to provide a practical output that spans a vast region.
2. Waves: To harvest energy from waves, extremely powerful ocean waves are necessary.
3. Tides: To collect energy from tides, extremely high tides are necessary. Tides are also affected by the relative locations of the Sun, Moon, as well as Earth.