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The source of Energy The formula Connecticut as example |
Niagara Falls produces about 2000 MW of electricity. Why don't we use
more hydropower in Connecticut, for example?
Water behind a dam has energy by virtue of being at high elevation. One kilogram has 9.8 joules of energy for every meter of elevation it has. A hydroelectric power plant uses that energy to turn a turbine, thereby to generate electricity. The power available depends upon how high the dam is, and how much water flows. The power available from a hydroelectric plant operating at about 85% efficiency can be calculated from The average year in Connecticut brings us about 1.1 meters of precipitation.
The land area of Connecticut is 5000 square miles, which is |
square meters. The total volume of water falling on Connecticut in one
year is about 
million
cubic meters. This amounts to 450 cubic meters per second. If we could
use all of the water falling on the state, and we had a 200-foot dam (61
meters) to hold the water, we could get about 230 MW out of it, which is
less than 10% of the Connecticut demand for electrical power. The Mayors
of New Haven, Bridgeport, and most other major Connecticut cities might
object to having their cities under water. So might environmentalists. 
