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News
hydropower capacity |
Author: Date:2012/9/11 14:27:36 |
Hydropower is very efficient
Efficiency = (electrical power delivered to the “busbar”) ÷ (potential energy of head water)
Typical losses are due to
Frictional drag and turbulence of flow
Friction and magnetic losses in turbine & generator
Overall efficiency ranges from 75-95%
Hydropower Calculations
HQPHQgP×××≅×××=ηη10
P = power in kilowatts (kW)
g = gravitational acceleration (9.81 m/s2)
η= turbo-generator efficiency (0<n<1)
Q = quantity of water flowing (m3/sec)
H = effective head (m)
Example:
Consider a mountain stream with an effective head of 25 meters (m)and a flow rate of 600 liters (ℓ)per minute. How much power could a hydro plant generate? Assume plant efficiency (η)of 83%.
H = 25 m
Q = 600 ℓ/min×1 m3/1000 ℓ×1 min/60sec
Q= 0.01 m3/sec
η= 0.83
P ≅10ηQH = 10(0.83)(0.01)(25) = 2.075
P≅2.1 kW
How much energy (E) will the hydro plant generate
each year?
E = P×t
E= 2.1 kW× 24 hrs/day ×365 days/yr
E= 18,396 kWh annually
About how many people will this energy support
(assume approximately 3,000 kWh / person)?
People = E÷3000 = 18396/3000 = 6.13
About 6 people |
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