Ram Pump and Solar Pump Training - Border Green Energy Team

1. Ram Pump
And
Solar Pump
Training
Fredrik Bjarnegard, Allen Chou, Sukon ”Tae” Phunpunyakorakul, Yotin Pupaolan, Salinee Tavaranan
A collaboration of
BGET TOPS ZOA KNCE TBCAF GREEN EMPOWERMENT PALANG THAI
B G E T
BORDER GREEN ENERGY TEAM
B G E TB G E T
BORDER GREEN ENERGY TEAM
Contact Us at
Border Green Energy Team
TOPS
34/53 Mae Sod – Mae Tao Rd
Mae Sod, TAK 63110
055-542-068
Or
Border Green Energy Team
c/o TOPS
PO Box 66
Mae Sod, TAK 63110
This manual is available at www.bget.org

2. List of contents
Introduction............................................................................................................................................. 3
Water – the primary source of life........................................................................................................ 3
Different ways of pumping water......................................................................................................... 3
Water Resources..................................................................................................................................... 5
Surface water vs Groundwater.............................................................................................................. 5
Water Demand...................................................................................................................................... 5
Water Storage ....................................................................................................................................... 6
Water Distribution ................................................................................................................................ 6
Solar pumping......................................................................................................................................... 8
The technology ..................................................................................................................................... 8
Performance........................................................................................................................................ 10
Designing a solar pumping system..................................................................................................... 11
Calculation example ........................................................................................................................... 11
Hydraulic ram pump............................................................................................................................ 13
Introduction......................................................................................................................................... 13
How a hydram works.......................................................................................................................... 13
Performance........................................................................................................................................ 15
Designing a hydraulic ram pump system............................................................................................ 16
Calculation example ........................................................................................................................... 17
Installation requirements .................................................................................................................... 18
References.............................................................................................................................................. 20
Appendix................................................................................................................................................ 21
Appendix A Formulae for Energy and Power............................................................................. 22
Appendix B Specification for Diesel Pump................................................................................ 23
Appendix C Specification for Solar Panels................................................................................. 24
Appendix D Specification for Yeser 12 V DC water pump........................................................ 25
Appendix E Hydraulic Ram Pump Tuning................................................................................. 31
Appendix F 1” Ram Pump Test Results..................................................................................... 33
Appendix G Steps in Installing Hydraulic Ram Pump System................................................... 40
Appendix H Problems and Solutions during Ram Pump Installation......................................... 41
2

3. Introduction
Water – the primary source of life
Water is the primary source of life for mankind and one of the most basic necessities for rural
development. Two-thirds of the world’s households use a water source outside the home1
. Often it
must be carried by hand, and since water is heavy it is very hard work. Therefore it is convenient to be
able to pump water.
Different ways of pumping water
Water pumping has a long history and many methods have been developed to pump water with a
minimum of effort. These have utilized a variety of power sources, namely human energy, animal
power, hydro power, wind, solar and fossil fuels for small generators. The relative merits of these are
laid out in Table 1 below.
Table 1 Comparison of pumping techniques
Type of pump Advantages Disadvantages
Hand pumps • local manufacture is possible
• easy to maintain
• low capital cost
• no fuel costs
• loss of human productivity
• often an inefficient use of boreholes
• only low flow rates are achievable
Animal driven pumps • more powerful than humans
• lower wages than human power
• dung may be used for cooking
fuel
• animals require feeding all year
round
• often diverted to other activities at
crucial irrigation periods
Hydraulic pumps
(e.g. rams)
• unattended operation
• easy to maintain
• low cost
• long life
• high reliability
• require specific site conditions
• low output
Wind pumps • unattended operation
• easy maintenance
• long life
• suited to local manufacture
• no fuel requirements
• water storage is required for low
wind periods
• high system design and project
planning needs
• not easy to install
Solar PV • unattended operation
• low maintenance
• easy installation
• long life
• high capital costs
• water storage is required for cloudy
periods
• repairs often require skilled
technicians
Diesel and gasoline pumps • quick and easy to install
• low capital costs
• widely used
• can be portable
• fuel supplies erratic and expensive
• high maintenance costs
• short life expectancy
• noise and fume pollution
1
Women, A World Report Debbie Taylor et al, UN/Methuen 1985.
3

4. All pumping techniques above have one thing in common. They require energy. In this training, we
will cover a few different energy sources that can be used for water pumping. These are diesel engines,
solar (photovoltaic [PV]) panels and ram pump. Diesel, gasoline, and kerosene pumps (including
windmills) have traditionally been used to pump water. However, reliable solar (photovoltaic [PV])
and ram pumps are becoming an attractive alternative to the traditional power sources. These
technologies, powered by renewable energy sources (solar and hydro), are especially useful in remote
locations where a steady fuel supply is problematic and skilled maintenance personnel are scarce.
4

5. Water Resources
Surface water vs Groundwater
The available water resource is an important criterion for choosing the kind of energy sources for any
given water pumping application. Water can come either from surface water or groundwater. Surface
water includes lakes, rivers, seawater, and rainwater; groundwater is found in underground aquifers,
including springs. Groundwater can be shallow or deep depending on the ground’s hydrological
formation. Surface water can dry up in the dry season depending on the kind of aquifer, the annual
rainfall, and the geographical location (such as arid, semiarid, and humid climates). These factors also
affect the depth of the water table.
The water resource identified should be large enough to fulfill the demand. Unusual climate changes
such as droughts and seasonal variation of the water table must be considered. In general, large
quantities of water are required for irrigation. The amount of water required for domestic water
supplies and livestock watering in rural areas generally depends on the size of the human and livestock
populations.
Water Demand
Water demand is another important criterion for designing rural water supply systems. The three main
areas of need are:
• Village water supply
• Water for livestock
• Water for irrigation
Water demand for village water supplies is estimated from population size and from the daily per
capita water consumption. A person needs 5 liters a day for drinking and cooking; 25 more to stay
clean. Water consumption also depends on the availability of water. Table 2 shows typical daily water
consumption for households with varying water access.
Table 2 Typical Daily Water Consumption for Households2
Type of Household Daily Water Consumption
(liters/person)
Households with dishwashers, washing
machines, and sprinklers
1,000
Households with a piped supply and taps 100-350
Households using a public hydrant in the
street
20-70
Households depending on a stream or
handpump several miles distant
2-5
2
Water for Agriculture, Sandra Postel (Worldwatch 1989)
5

6. Similarly, demand for livestock watering is estimated from the number of animals using the system
multiplied by the per capita water consumption. Typical daily water consumption for farm animals is
shown in Table 3.
Table 3 Typical Daily Water Consumption for Farm Animals
Type of Animal Daily Water Consumption
(liters/animal)
Dairy cows 80
Beef brood cows 50
Horses and mules 50
Calves 30
Pigs 20
Sheep and goats 10
Chickens 0.1
Unlike demands for domestic and livestock water supplies, water demand for crop irrigation is
seasonal. Because some crops require a maximum water supply for a relatively short growing season,
all irrigation systems need to be designed for peak water demands. Estimating the water demand for an
irrigation application is complex and is beyond the scope of this training. However, local practice and
experience are probably the best guides to estimating water requirements for a specific application.
Table 4 shows the estimated daily water requirements for various types of crop irrigation.
Table 4 Estimated Maximum Daily Water Demand for Various Types of Crop Irrigation
Crops Daily Water Requirement
(m3/ha)
Rice 100
Rural village farms 60
Cereals 45
Sugar cane 65
Cotton 55
Water Storage
Storage is necessary for good water management. The available power resource must be considered
when determining storage size. The size of water tanks for conventional systems depends only on the
peak and average daily water demand. PV systems, on the other hand, depend on daily weather
conditions. Cloudy days with poor solar radiation create problems for meeting the daily water demand,
so water tanks should be larger for such systems. Generally, 3 days of storage is recommended for
renewable energy water pumping systems. Water tanks can be smaller if alternative water sources,
such as hand pumps and rainwater, are available. In rural areas rainwater can be collected to water
livestock and wash clothes, depending on the amount of annual rainfall distribution in the area. Surface
water that flows year-round (such as a river) can also be used for such tasks, reducing the need for
large capacity water tanks.
Water Distribution
To distribute water fairly to the rural community, pumping it first to the tank and then distributing it
from the tank by using gravity is recommended. This way, enough pressure can be built up at the water
tank to distribute water by gravity. In addition, water will continuously flow in the tank, which helps to
reduce the growth of bacteria. Finally, this helps maintain any leakage with little water loss and few
interruptions to other distribution areas. However, distribution pipes must be sized carefully because
6

7. smaller pipes create more friction than bigger pipes. Because oversized distribution pipes will raise the
investment costs of the system, there are tradeoffs. The rural distribution network is relatively small, so
leakage in these systems is less of a concern than in city water supplies. The water pressure in the
distribution pipe is generally low in these systems and the chances of the pipe bursting are very
unlikely.
7

8. Solar pumping
PV technology converts the sun’s energy into electricity (DC) when the PV module (array) is exposed
to sunlight. The PV module can also be used for AC applications using an inverter. PV is especially
suitable for water pumping because energy need not be stored for night pumping. Instead, water can be
stored to supply water at night.
The technology
Solar pump systems are broadly configured into 5 types as described below:
Submerged multistage centrifugal motor pumpset (Figure 1)
This type is probably the most common type of solar pump
used for village water supply. The advantages of this
configuration are that it is easy to install, often with lay-flat
flexible pipework and the motor pumpset is submerged
away from potential damage. Either ac or dc motors can be
incorporated into the pumpset although an inverter would
be needed for ac systems. If a brushed dc motor is used
then the equipment will need to be pulled up from the well
(approximately every 2 years) to replace brushes. If
brushless dc motors are incorporated then electronic
commutation will be required. The most commonly
employed system consists of an ac pump and inverter with
a photovoltaic array of less than 1500Wp.
Figure 1 Submerged multistage centrifugal motor pumpset
Submerged pump with surface mounted motor (Figure 2)
This configuration was widely installed with turbine
pumps in the Sahelian West Africa during the 1970s. It
gives easy access to the motor for brush changing and
other maintenance. The low efficiency from power
losses in the shaft bearings and the high cost of
installation has been disadvantages. In general this
configuration is largely being replaced by the
submersible motor and pumpset.
Figure 2 Submerged pump with surface mounted motor
8

9. Reciprocating positive displacement pump (Figure 3)
The reciprocating positive displacement pump (often
known as the jack or nodding donkey) is very suitable for
high head, low flow applications. The output is
proportional to the speed of the pump. At high heads the
frictional forces are low compared to the hydrostatic forces
often making positive displacement pumps more efficient
than centrifugal pumps for this situation. Reciprocating
positive displacement pumps create a cyclic load on the
motor which, for efficient operation, needs to be balanced.
Hence, the above ground components of the solar pump are
often heavy and robust, and power controllers for
impedance matching often used.
Figure 3 Reciprocating positive displacement pump
Floating motor pump sets (Figure 4)
The versatility of the floating unit set, makes it ideal for
irrigation pumping for canals and open wells. The pumpset is
easily portable and there is a negligible chance of the pump
running dry. Most of these types use a single stage
submersed centrifugal pump. The most common type utilises
a brushless (electronically commutated) dc motor. Often the
solar array support incorporates a handle or 'wheel barrow'
type trolley to enable transportation.
Figure 4 Floating motor pump sets
Surface suction pumpsets (Figure 5)
This type of pumpset is not recommended except where an
operator will always be in attendance. Although the use of
primary chambers and non-return valves can prevent loss
of prime, in practice self-start and priming problems are
experienced. It is impractical to have suction heads of
more than 8 meters.
Figure 5 Surface suction pumpsets
9

10. Performance
The performance of some commercially available products is shown in Figure 6. It can be seen that
solar pumps are available to pump from anywhere in the range of up to 200m head and with outputs of
up to 250m3
/day. The product of head and output is defined as m4
. DC pumps normally have m4
value
below 1500-2000. Many systems pump water using solar energy with m4
above 2000, but here they
use AC pumps and inverters and are getting into much larger systems. The m4
diagram of the 50W DC
pump that we will use for demonstration purposes during this training can be found in Appendix D.
Figure 6 Performance of solar pumps
Solar pumping technology continues to improve. In the early 1980s the typical solar energy to
hydraulic (pumped water) energy efficiency was around 2% with the photovoltaic array being 6-8%
efficient and the motor pumpset typically 25% efficient. Today, an efficient solar pump has an average
daily solar energy to hydraulic efficiency of more than 4%. Photovoltaic modules of the
10

11. monocrystalline type now have efficiencies in excess of 12% and more efficient motor and pumpsets
are available. A good sub-system (that is the motor, pump and any power conditioning) should have an
average daily energy throughput efficiency of 30-40%.
Designing a solar pumping system
The first steps in doing a solar pumping project are:
1. Determine the demand in water
How many liters or m3
(1000 liters) per day?
2. Determine the characteristics of the available water supply
Is the source from surface water or groundwater?
3. Determine the head
How many meters does the water need to be pumped from the available water source to the storage
tank?
4. Figure out the m4
product to see if this is a do-able project
Multiply the required output (m3
/day) and the head (m) to determine what type of pump is needed.
5. Calculate the array size to determine if this is going to fit in a budget
The energy required to pump water is calculated by the following formula:
hgmW ××=
where W is the energy in Joule (J), m is the mass of the water in kilograms (kg), g is the constant of
gravity (~10 m/s2
), and h is the head in meters (m).
Power is the amount of energy per time and is expressed in Watts (W).
t
W
P =
where P is the power in Watts (W), W is the energy in Joule (J), and t is the time in seconds (s).
Because of inefficiencies in both the pump and the solar panel, the required input is larger than the
power output. This is described by the following formula.
f
P
P o
i =
where Pi is the required input power (from the solar panel), Po is the power output (the water pumped
to a higher altitude), and f is the efficiency (eg. 1 is 100% efficiency and 0.5 is 50% efficiency).
Calculation example
1. Determine the demand in water
A village needs domestic water supply for 500 people. The average consumption per person would be
40 liters.
Total water demand: 500 x 40 liters/day = 20,000 liters/day = 20 m3
/day
11

12. 2. Determine the characteristics of the available water supply
The village has a well with a depth of 3 meters, and a storage tank elevated on a hill, with the top of
the tank 15 meters above the ground where the well is.
3. Determine the head
The head would be the 3 meters that the water has to be pumped up to ground level, plus 15 meters to
the top of the tank, plus an allowance of about 10% for friction loss in the pipe, (which you would
really calculate instead of assume), for about 20 meters of head.
4. Figure out the m4
product to see if this is a do-able project
The m4
product would be 20 m x 20 m3
/day = 400m4
/day. Figure 6 shows that this is the region for a
DC MSC (multistage centrifugal) pump with a solar array of between 600 W and 1400 W.
5. Calculate the array size to determine if this is going to fit in a budget
The required energy per day would be:
MJJhgmW 4000,000,42010000,20 ==××=××=
Assuming we can get an average of 3 hours of sunlight per day, this is:
sh 800,10606033 =××=
The required power output would be:
W
t
W
Po 370
800,10
000,000,4
===
With a total system efficiency of 30% this would require a solar array of:
WPi 1235
3,0
370
== , which is between 600 W and 1400 W as indicated in Figure 6.
12

13. Hydraulic ram pump
Introduction
The hydraulic ram pump, or hydram, concept was first developed by the Mongolfier brothers in France
in 1796 (they are better remembered for their pioneering work with hot-air balloons).
Essentially, a hydram is an automatic pumping device which utilizes a small fall of water to lift a
fraction of the supply flow to a much greater height; i.e. it uses a larger flow of water falling through a
small head to lift a small flow of water through a higher head. The main virtue of the hydram is that its
only moving parts are two valves, and it is therefore mechanically very simple. This gives it very high
reliability, minimal maintenance requirements and a long operation life.
How a hydram works
Its mode of operation depends on the use of the phenomenon called water hammer and the overall
efficiency can be quite good under favorable circumstances. More than 50% of the energy of the
driving flow can be transferred to the delivery flow.
Figures 7-10 illustrates the principle; initially (Figure 7) the impulse valve (or waste valve since it is
the non-pumped water exit) will be open under
gravity (or in some designs it is held open by a
light spring) and water will therefore flow down
the drive pipe (through a strainer) from the water
source. As the flow accelerates, the hydraulic
pressure under the impulse valve and the static
pressure in the body of the hydram will increase
until the resulting forces overcome the weight of
the impulse valve and start to close it. As soon
as the valve aperture decreases, the water
pressure in the hydram body builds up rapidly
and slams the impulse valve shut.
The moving column of water in the drive pipe is
no longer able to exit via the impulse valve so its
velocity must suddenly decrease; this continues to
cause a considerable rise of pressure which forces
open the delivery valve to the air-chamber. Once
the pressure exceeds the static delivery head,
water will be forced up the delivery pipe (Figure
8).
Figure 8
Figure 7
13

14. Air trapped in the air chamber is
simultaneously compressed to a pressure
exceeding the delivery pressure. Even-
tually the column of water in the drive
pipe comes to a halt and the static pressure
in the casing then falls to near the supply
head pressure. The delivery valve will then
close, when the pressure in the air
chamber exceeds that in the casing. Water
will continue to be delivered after the
delivery valve has closed until the
compressed air in the air chamber has
expanded to a pressure equal to the
delivery head (Figure 9). The air chamber
is a vital component, as apart from
improving the efficiency of the process by
allowing delivery to continue after the
delivery valve has closed, it is also essential to cushion the shocks that would otherwise occur due to
the incompressible nature of water.
Figure 9
A check valve is included in the delivery pipe to
prevent return flow. When the delivery valve closes,
the reduced pressure in the hydram body will allow
the impulse valve to drop under its own weight,
thereby letting the cycle start all over again (Figure
10). Most hydrams operate at 30-100 cycles a minute.
Figure 10
This cycling of the hydram is timed by the
characteristic of the waste valve. Normally it can be
weighted or pre-tensioned by an adjustable spring, and
an adjustable screwed stop is generally provided
which will allow the maximum opening to be varied.
The efficiency, which dictates how much water will
be delivered from a given drive flow, is critically
influenced by the valve setting.
This is because if the waste valve stays open too long, a smaller proportion of the throughput water is
pumped, so the efficiency is reduced, but if it closes too readily, then the pressure will not build up for
long enough in the hydram body, so again less water will be delivered. There is often an adjustable bolt
that limits the opening of the valve to a predetermined amount, which allows the device to be turned to
optimize its performance. A skilled installer should be able to adjust the waste valve on site to obtain
optimum performance. Please refer to Appendix E for further information regarding hydraulic ram
pump tuning. A storage tank is usually included at the top of the delivery pipe to allow water to be
drawn in variable amounts as needed.
14

15. Performance
The flow of water that a hydraulic ram pump can deliver depends on the head (H) and flow (Q) of the
water from the drive pipe, as well as the delivery head (h), i.e. the height difference between the ram
pump and the storage tank where the water should be pumped. The delivery flow (q) can be calculated
using the following formula:
h
QH
fq
×
×=
where f is the efficiency factor, H is the supply head, Q is the supply flow, and h is the delivery head.
A typical efficiency factor for commercial ram pumps is 60%, but up to 80% is possible. For home
made ram pumps this is usually lower.
H
D
h
d
Catchment tank
q
l
L
Q
Drive pipe
Delivery pipe
Storage tank
Ram pump
Figure 11 Schematic of ram pump installation
The size and length of the drive pipe must be in
proportion to the working head from which the ram
operates. Also, the drive pipe carries severe internal
shock loads due to water hammer, and therefore normally
should be constructed from good quality steel water pipe.
Normally the length (L) of the drive pipe should be
around three to seven times the supply head (H). Ideally
the drive pipe should have a length of at least 100 but not
more than 1,000 times its own diameter (D). The drive
pipe must generally be straight; any bends will not only
cause losses of efficiency, but will result in strong
fluctuating sideways forces on the pipe, which can cause
it to break loose.
Technical Parameters for
Hydraulic Ram Pump System
,
where
L = length of drive pipe
H = supply head
D = diameter of drive pipe
000,1100) −=
D
L
b73) −=
H
L
a
Hydrams are mostly intended for water supply duties, in hilly or mountainous areas, requiring small
flow rates delivered to high heads. They are less commonly used for irrigation purposes, where the
higher flow rates required will usually demand the use of larger sizes of hydram having 6-inch or 4-
inch drive pipes. Manufacturers usually describe the size of a hydram by the supply and delivery pipe
diameters (generally given in inches even in metric countries because of the common use of inch sizes
15

16. for pipe diameters); e.g. a 6 x 3 hydram has a 6-inch diameter drive pipe and a 3-inch diameter
delivery pipe. Table 5 indicates estimated performance for typical 4-inch x 2-inch and 6-inch x 3-inch
commercial hydrams.
Table 5 Typical ram pump performance data
Hydram size in inches 4” x 2” 6” x 3”
Head ratio (h/H) 5 10 15 20 5 10 15 20
Drive flow Q (litres/s) 9.0 9.7 10.0 9.0 20.2 17.2 17.1 19.3
Delivery flow q (m3
/day) 94 51 35 23 216 101 69 50
Efficiency f 61% 61% 61% 59% 62% 68% 70% 60%
The ram pump that will be used for demonstration purposes during this training is manufactured by the
AID foundation in the Philippines. It has a 1” drive pipe and a ½” delivery pipe. The performance data
for this ram pump can be found in Appendix F.
Designing a hydraulic ram pump system
The following are the steps in designing a hydraulic ram pump system:
1. Identify the necessary design factors:
1. What is the available supply head, H (the height difference between the water source and the pump
site)?
2. What is the required delivery head, h (the difference in height between the pump site and the point
of storage or use)?
3. What is the available drive flow, Q (the quantity of flow from the water source)?
4. What is the required delivery flow, q (the quantity of water for consumption)?
5. What is the length of the drive pipe, L (the distance from the source to the pump site)?
6. What is the length of the delivery pipe, l (the distance from the pump to the storage site)?
2. Determine if this is a do-able project
Calculate the required efficiency factor using the formula
QH
qh
f
×
×
=
to see if it is possible to use a ram pump to meet the supply demand.
The angle of the drive pipe should not be too steep. Normally the length (L) of the drive pipe should be
around three to seven times the supply head (H).
3. Determine the ram pump size
The table below shows the capacities for different ram pump sizes from a certain manufacturer, as well
as the recommended size of the drive pipe.
Table 6 Capacities for different ram pump sizes3
Hydram size 1 2 3 3.5 4 5X 6X
Drive flow needed
(liters/min)
7-16 12-25 27-55 45-96 68-137 136-270 180-410
Maximum lift (meters) 150 150 120 120 120 105 105
Drive pipe size (inches) 1¼” 1½” 2” 2½” 3” 4” 5”
3
US AID, 1982
16

17. 4. Determine the drive and delivery pipe size
The drive pipe diameter is usually chosen based on the size of the ram and the manufacturer's
recommendations as shown in Table 6. But there are also other factors to consider. The diameter of
both the drive pipe and the delivery pipe should not be smaller than their respective length divided by
1,000. If the diameter is too small the capacity will be reduced due to friction losses. The diameter
should also be large enough to handle the flow of water that should go through it. The table below can
be used for finding the right pipe size for the available flow.
Table 7 Possible flows for different pipe sizes4
Pipe diameter (inches) 1” 1.5” 2” 3” 4”
Flow (liters/min) 6-36 37-60 61-90 91-234 235-360
Calculation example
A small community consists of 10 homes with a total of 60 people. There is a spring l0m lower than
the village, which drains to a wash 15m below the spring. The spring produces 30,000 liters of water
per day. There is a location for a ram on the bank of the wash. This site is 5m higher than the wash and
35m from the spring. A public standpost is planned for the village 200m from the ram site. The lift
required to the top of the storage tank is 23m.
1. Identify the necessary design factors:
1. The available supply head, H, is 10m.
2. The required delivery head, h, is 23m to the top of the storage tank.
3. The quantity of flow available, Q, equals 30,000 liters per day divided by 1,440 minutes per day
(30,000/1,440) = 20.8 liters per minute.
4. The quantity of water required, q, assuming 40 liters per day per person as maximum use is 60
people x 40 liters per day = 2,400 liters per day.
2,400/1,440 = 1.66 liters per minute (use 2 liters per minute)
5. The length of the drive pipe, L, is 35m.
6. The length of the delivery pipe, l, is 200m.
2. Determine if this is a do-able project
Calculate the required efficiency factor using the formula
22.0
8.2010
223
=
×
×
=
×
×
=
QH
qh
f
22% efficiency is VERY do-able for a hydraulic ram pump installation.
Calculate the ratio between the length of the drive pipe (L) and the supply head (H).
5.3
10
35
==
H
L
The length of the drive pipe should be at least three times the supply head, so this condition is also met.
3. Determine the ram pump size
Table 6 can now be used to select a ram size. The volume of driving water or supply needed is 20.8
liters per minute. From Table 6, a No. 2 Hydram requires from 12 to 25 liters per minute. A No. 2
4
US AID, 1982
17

18. Hydram can lift water to a maximum height of 150m according to Table 6. This will be adequate since
the delivery head to the top of the storage tank is 23m. Thus, a No. 2 Hydram would be selected.
4. Determine the drive and delivery pipe size
Table 6 shows that for a No. 2 Hydram, the minimum drive pipe diameter is 1½ inch. The length of the
drive pipe is 35 meters, so the diameter should not be less that 35 mm. Thus a 1½” (38 mm) pipe
would be sufficient. Table 7 shows that a 1½” pipe is sufficient for the drive flow (20.8 liters/min).
For the delivery flow (2 liters/min), Table 7 shows that a 1” pipe is sufficient
Installation requirements
Figure 12 illustrates a typical hydram installation, pumping water to a small storage tank on a plateau.
It can be seen that the supply head is created in this case by creating a weir. In some cases a small
stream is diverted to provide the water supply.
Figure 12 Typical ram pump installation
18

19. Where greater capacity is needed, it is
common practice to install several
hydrams in parallel. This allows a
choice of how many to operate at any
one time so it can cater for variable
supply flows or variable demand.
Figure 13 shows an installation with
parallel ram pumps.
Figure 13
Multiple hydrams with
common delivery pipe
The hydram body requires to be firmly bolted to a concrete foundation, as the beats of its action apply
a significant shock load. The hydram should be located so that the waste valve is always located above
flood water level, as the device will cease to function if the waste valve becomes submerged. The
delivery pipe can be made from any material capable of carrying the pressure of water leading to the
delivery tank. In all except very high head applications, plastic pipe can be considered; with high
heads, the lower end of the delivery line might be better as steel pipe. The diameter of the delivery line
needs to allow for avoiding excessive pipe friction in relation to the flow rates envisaged and the
distance the water is to be conveyed. It is recommended that a hand-valve or check-valve (non-return
valve) should be fitted in the delivery line near the outlet from the hydram, so that the delivery line
does not have to be drained if the hydram is stopped for adjustment or any other reason. This will also
minimize any back flow past the delivery valve in the air chamber and improve efficiency.
For steps in installing hydraulic ram pump systems, please refer to Appendix G.
For problems that may occur during installation of ram pump systems, please refer to Appendix H.
19

20. References
The material for this training manual has been taken from the following sources:
N. Argaw, R. Foster and A. Ellis, New Mexico State University, Las Cruces, New Mexico, USA,
“Renewable Energy for Water Pumping Applications in Rural Villages”, NREL/SR-500-30361
Available electronically at http://www.osti.gov/bridge
Technical Information Service
Practical Action (formerly: Intermediate Technology Development Group)
The Schumacher Centre for Technology and Development
Bourton-on-Dunsmore
Rugby, CV23 9QZ
United Kingdom
Tel: (+44) 1926 634400
Fax: (+44) 1926 634401
e-mail: infoserv@practicalaction.org.uk
web: http://www.itdg.org
http://www.itdg.org/docs/technical_information_service/solar_pv_waterpumps.pdf
http://www.itdg.org/docs/technical_information_service/hydraulic_ram_pumps.pdf
AID Foundation
Alternative Indigenous Development Foundation Inc.
PO Box 297
Lot 30, Blk. 12, Puentebella Subd.,
Brgy. Taculing, Bacolod City,
Philippines
Tel: (+63) 34 446 3629
Fax: (+63) 34 446 2336
e-mail: aidfi@hotmail.com
web: www.aidfi.org
Other websites
http://www.newint.org/issue207/facts.htm
http://www.thefarm.org/charities/i4at/lib2/hydrpump.htm
http://www.dekpower-fj.com/diesel-water.htm
http://www.solartron.co.th/Newer/product.aspx
20

21. Appendix
Appendix A Formulae for Energy and Power (1 page)
Appendix B Specification for Diesel Pump (1 page)
Appendix C Specification for Solar Panels (1 page)
Appendix D Specification for Yeser 12 V DC water pump (6 pages)
Appendix E Hydraulic Ram Pump Tuning (2 pages)
Appendix F 1” Ram Pump Test Results (7 pages)
Appendix G Steps in Installing Hydraulic Ram Pump System (1 page)
Appendix H Problems and Solutions during Ram Pump Installation (2 pages)
21

22. Appendix A Formulae for Energy and Power
Energy can be in many different forms. It can never be destroyed, only transformed from one form of
energy to another.
Potential energy, e.g. water stored in a reservoir
hgmW ××=
where W is the energy in Joule (J), m is the mass of the water in kilograms (kg), g is the constant of
gravity (~10 m/s2
), and h is the head in meters (m).
Electrical energy, e.g. stored in a battery
QUW ×=
where W is the energy in Joule (J), U is the voltage in Volts (V), and Q is the electric charge in
Coulomb (C).
Power is the amount of energy per time and is expressed in Watts (W).
t
W
P =
where P is the power in Watts (W), W is the energy in Joule (J), and t is the time in seconds (s).
Water power, e.g. water flowing in a waterfall
hgqP ×××= ρ
where P is the power in Watts (W), ρ is the water density in kg/m3
, q is the flow in m3
/s, g is the
constant of gravity (~10 m/s2
), and h is the head in meters (m).
Electrical power, e.g. produced in a solar panel
IUP ×=
where P is the electrical power in Watts (W), U is the voltage in Volts (V), and I is the current in
Amperes (A).
22

23. Appendix B Specification for Diesel Pump
23

24. Appendix C Specification for Solar Panels
24

25. Appendix D Specification for Yeser 12 V DC water pump
25

26. 26

27. 27

28. 28

29. 29

30. 30

31. Appendix E Hydraulic Ram Pump Tuning
31

32. 32

33. Appendix F 1” Ram Pump Test Results
33

34. 34

35. 35

36. 36

37. 37

38. 38

39. 39

40. Appendix G Steps in Installing Hydraulic Ram Pump System
40

41. Appendix H Problems and Solutions during Ram Pump Installation
41

42. 42