Evaluating Pump at Turbine (PAT) and Pressure Reducing Valve (PRV)

This report provides a comparative analysis of Pump as Turbine (PAT) and Pressure Reducing Valve (PRV) systems for water pipeline control, discussing their efficiency, reliability, and environmental impact. It highlights the advantages of PAT in handling large water volumes and generating electricity, while acknowledging PRV's precision in pressure management and leakage reduction. The report concludes that PAT is generally superior due to its water handling capacity, power efficiency, and longevity, despite PRV's advantages in specific pressure control scenarios and lower initial cost. Desklib offers students access to this solved assignment and other valuable study resources.

Running head: HYDRAULICS SYSTEMS
Hydraulics Systems
Name of the Student
Name of the University
Author Note

1HYDRAULICS SYSTEMS
1. Which of “Pump at Turbine” (PAT) & “Pressure Reducing Valve”
(PRV) works efficient in controlling of water in pipe line from upstream to
downstream? Discuss.
Both of the Pump as Turbine and the Pressure Reducing Valve has their own
advantages in the case of water flow controls. Comparing this two methods of the water flow
it is measured that Pump as Turbine has a better advantage over the Pressure reducing valve
to control the water flow (Jain et al. 2015). This is because the Pump as Turbine can produce
a maximum flow of a given section of water. In the case of conventional pumping mode and
controlling the water, the Pump as Turbine works better than the Pressure Reducing Valve as
the Pump as Turbine is able to handle a large amount of water. The Pump as Turbine can
create a greater speed variation which gives an extra edge to the Pump as Turbine over the
Pressure Reducing Valve in the case of water flow control. Both of the Pump as Turbine and
the Pressure Reducing Valve can efficiently control the water flow of the water but the main
advantage of the Pump as Turbine over the Pressure Reducing Valve is that it can also
produce the electrical energy with it which makes it more efficient. Also, the Pressure
Reducing Valve disperse the energy of pressure which add a head loss to the system and this
opposes the modern principle of the resource use (Song, Park and Park 2013).
2. Why “Pump at Turbine” (PAT) is more efficient and more reliable
comparing to “Pressure Reducing Valve” (PRV)?
The Pump as Turbine is a reliable and efficient system compared to the Pressure
Reducing Valve. The main advantage of the Pump as Turbine over the Pressure Reducing
value is that the operation cost of this is low. With the low power consumption, the Pump as
Turbine can also produce the electricity power besides controlling the water flow which
makes it super-efficient in this case. While the Pressure as Turbine runs at the reverse from

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the conventional way, the shaft torque of the motor can be used in a various way. Compared
to the Pressure Reducing Valve the Pump as Turbine can achieve a maximum flow rate of the
water (Lima, Junior and Brentan 2017). In such a situation where the pressure drop has
reduced the energy produced by the Pump as Turbine, the production of the energy is very
much high. The Pump as Turbine uses a low power consumption but it does not mean the
output of the Pump as Turbine is low compared to Pressure Reducing Valve. The pressure
control of the Pump as Turbine and the Pressure Reducing Valve is the same when the total
consumption is high. Also, the Pump as Turbine can be used in the cases of fluctuating water
flow by different size of units which is missing in the Pressure Reducing Valve (Jain and
Patel 2014).
3. Why “Pressure Reducing Valve” (PRV) is more efficient and more
reliable compare to “Pump at Turbine” (PAT)?
There are many advantages of the Pump as Turbine but still, the Pressure Reducing
Valve has some of its own advantages over the Pump as Turbine. The Pressure Reducing
Valve can be used for perfectly controlling the pressure of the water. Thus by accurately
managing the pressure of the water, the water can be saved. Managing the pressure of the
water accurately is not possible for the Pump as Turbine. Also, the Pressure Reducing Valve
can significantly reduce the leakages in the water flow pipeline to mitigate the disruption
issues of the water flow (Fecarotta et al. 2015). In the cases of low power consumption the
Pump as Turbine fails to produce enough head loss to reduce the pressure in the manageable
standards where the Pressure Reducing Valve works with the same accuracy of the pressure
reducing. In this type of situation, it is not possible to ensure a constant outlet pressure by
using just one Pump as Turbine. For managing this situation more than one Pump as Turbine
can be integrated together but this increases the power consumption of the system. The
mechanism of the Pressure Reducing Valve is much simple compared to the Pump as

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Turbine. In many cases, the Pump as Turbine faces the low power arrangement issue while
Pressure Reducing Valve can work in this cases.
4. Summarizing the finding, which of the PRV or PAT pump is better,
more efficient, environmentally friendly, long life cycle, serviceable, cost,
price etc.
From the above discussion, it is determined that the Pump as Turbine is better compared to
the Pressure Reducing Valve. It is better in the context of water handling. The Pump as
Turbine can handle a large amount of water compared to the Pressure Reducing Valve.
Though in the water pressure handling cases the Pressure Reducing Valve works in a very
much efficient way but the Pump as Turbine also can achieve this much efficiency by
implementing an additional unit of the Pump as Turbine. For the case of power efficiency, the
Pump as Turbine works more efficiently compared to the Pressure Reducing Valve as the
Pump as Turbine can also generate the electric power while running (Raman et al. 2013).
This reduces the overall running cost of the Pump as Turbine, while the Pressure Reducing
Valve is unable to generate any type of power while running. In the environment related
cases the Pressure Reducing Valve has no effect on the environment because of the small size
of this. The Pump as Turbine has also a negligible effect on the environment but in some
cases where the micro-hydro power project has implemented the Pump as Turbine can affect
the normal water flow of the rivers, streams which can affect the environment. The Pressure
Reducing Valve needs to be repaired in every three to five years where the Pump as Turbine
can run over ten years without any repair. So in this case also the Pump as Turbine is better.
Both of the Pressure Reducing Valve and the Pump as Turbine are serviceable but the cost of
the Pump as Turbine is much higher compared to a Pressure Reducing Valve.

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References:
Fecarotta, O., Aricò, C., Carravetta, A., Martino, R. and Ramos, H.M., 2015. Hydropower
potential in water distribution networks: Pressure control by PATs. Water resources
management, 29(3), pp.699-714.
Jain, S.V. and Patel, R.N., 2014. Investigations on pump running in turbine mode: A review
of the state-of-the-art. Renewable and Sustainable Energy Reviews, 30, pp.841-868.
Jain, S.V., Swarnkar, A., Motwani, K.H. and Patel, R.N., 2015. Effects of impeller diameter
and rotational speed on performance of pump running in turbine mode. Energy conversion
and management, 89, pp.808-824.
Lima, G.M., Junior, E.L. and Brentan, B.M., 2017. Selection and location of Pumps as
Turbines substituting pressure reducing valves. Renewable Energy, 109, pp.392-405.
Raman, N., Hussein, I., Palanisamy, K. and Foo, B., 2013. An experimental investigation of
pump as turbine for micro hydro application. In IOP conference series: Earth and
environmental science (Vol. 16, No. 1, p. 012064). IOP Publishing.
Song, X.G., Park, Y.C. and Park, J.H., 2013. Blowdown prediction of a conventional pressure
relief valve with a simplified dynamic model. Mathematical and Computer Modelling, 57(1-
2), pp.279-288.