Question

2. Why is the supply of electricity from hydroelectric sources not constant around the
year?

Answer 1

Answer:

Hydropower is fueled by water, so it's a clean fuel source, meaning it won't pollute the air like power plants that burn fossil fuels, such as coal or natural gas.

Explanation:

MARK ME AS BRAINLIST

Answer 2

Answer: Hydropower is fueled by water, so it's a clean fuel source, meaning it won't pollute the air like power plants that burn fossil fuels, such as coal or natural gas.

Hydropower works as -: Hydro Project works on potential energy in stored water due to water head and quantity of water.

Dam is constructed to store water behind in the reservoir . Water head is created due to dam height. Quantity of Water available depends on the capacity of the reservoir.

There are 3 main types of impulse turbine in use: the Pelton, the Turgo, and the Crossflow turbine. The two main types of reaction turbine are the propeller turbine (with Kaplan variant) and the Francis turbine. The reverse Archimedes Screw and the overshot waterwheel are both gravity turbines.

The power available from falling water can be calculated from the flow rate and density of water, the height of fall, and the local acceleration due to gravity. In SI units, the power is:

P= npQgh.

where

P is power in watts

n is the dimensionless efficiency of the turbine

p is the density of water in kilograms per cubic metre

Q is the flow in cubic metres per second

g is the acceleration due to gravity

h is the height difference between inlet and outlet in metres.

To illustrate, power is calculated for a turbine that is 85% efficient, with water at 1000 kg/cubic metre (62.5 pounds/cubic foot) and a flow rate of 80 cubic-meters/second (2800 cubic-feet/second), gravity of 9.81 metres per second squared and with a net head of 145 m (480 ft).

In SI units:

Power (W)=0.85×1000×80×9.81×145

which gives 97 MW

In English units, the density is given in pounds per cubic foot so acceleration due to gravity is inherent in the unit of weight. A conversion factor is required to change from foot lbs/second to kilowatts:

Power (W)=0.85×62.5×2800×480×1.35

which gives 97 MW (130,000 horsepower)