c) The level of water on one side of a hydroelectric power plant is limited to 500 m while a
other side water level is 300 m. The mass flow rate of water is limited to 50,000 kg/s and
the overall turbine efficiency is 85%. If the total head losses between the two slevations ta
15 m, estimate the total output power generated from the plant. Determine the type of
turbine to be installed to satisfy these requirements if the desired rotational speed is 1000
rpm?
[18 Marks]
Question (4) [30 Marks]
a) State three parts can be used as safety components in nents in solar thermal systems....... [5 Marks]
b) Draw suitable curves to show the temperature distributions of (a) solar absorber (b) fluid,
of a thermosiphon parallel tubes type flat plate solar collector along the length and the
........... [5 Marks]
width of the collector.
......
c) A Darrieus rotor type wind turbine with a rotor diameter of 11 m is installed in a wind
farm where the measured wind speed is 8 m/s. Calculate the following:
i. The power of the incoming wind.
..[5 Marks]
ii. The theoretical maximum power that could be extracted from the wind.... [5 Marks]
iii. A reasonable attainable turbine power and the corresponding torque and RPM...
..[10 Marks]
Power coefficient
Turbine tip sp
Question (5) 125 Total marks]
Verzasca hydroelectric power station in Switzerland receives water from Contra dam reservoir at
470 m above sea level is transferred to an underground power station downstream at 193 m above
sea level. The power plant can discharge up to 50,000 kg/s and the overall turbine efficiency is
95%. If the total head loss between the two elevations is 50 m and the desired rotational speed is
800 rpm, Find
i.
(17 Marks)
The total output power generated from the Verzasca power plant.
Someone claims that they are using Pelton wheel turbine, is his claim true? and why?
18 Marks]
0.98
Pelton wheel
0.94
Francis turbines Axial flow turbines
0.90
Efficiency in per cent
0.86
0.82
0
1
2
2
3
Dimensionless specific speed
4
