Answer: because water is much more dense than air, tidal energy is more powerful than wind energy. Unlike wind, tides are predictable and stable. Where tidal generators are used, they produce a steady, reliable stream of electricity
The difference between granites and basalts is in silica content and their rates of cooling. A basalt is about 53% SiO2, whereas granite is 73%. Intrusive, slowly cooled inside the crust.
