performance evaluation of solar water pump

PERFORMANCE EVALUATION OF SOLAR WATER PUMP DISCHARGE
EFFICIENCY AT VARIABLE HEADS UNDER DIFFERENT WEATHER
CONDITION AND PROSPECTS OF SOLAR RADIATION
Basharat Javaid
Director, Water Management Training Institute, Lahore
Directorate General Agriculture
(Water Management) Punjab

INTRODUCTION
‣ The sun is the natural source of energy for an independent water
supply. Solar pumps operate anywhere the sun shines, and the longer
it shines, the more water they pumps
‣ Agricultural production through irrigation with electric tubewells is hit
badly by energy crises as the grid electricity in remote areas is
extremely short
‣ The use of renewable energy resources and replacement of existing
non-renewable energy source of fossil fuels for irrigation tubewells
with renewable energy such as solar or wind could be a viable option

PROSPECTS OF SOLAR ENERGY IN PAKISTAN
• Solar energy is available for more than 300 days a year in Pakistan
with about 6-8 hours effective daylight hours.
• Most parts of the Pakistan receive very high solar radiation
intensities about (5kwh/m 2 /day)
• The arid/ semi-arid climate of the Punjab provides ideal conditions for
adoption of solar energy for operating irrigation water pumps.
• In the present scenario, when the electricity is insufficient for
domestic use and fuel prices are increasing exponentially, solar
water pumps could be a viable solution for irrigation

PROSPECTS OF SOLAR ENERGY IN PAKISTAN

IMPORTANCE OF SOLAR WATER PUMPING
• A natural match between the availability of sunlight and the need
for water.
• A reliable, efficient, sustainable and cost effective energy option
for agriculture
• It will create awareness among the farming community for
conservation of resources and helped them to overcome
hesitation in adoption of new interventions

JUSTIFICATION
• More than one million tubewells in Pakistan including 750,000 diesel and
70,000 electricity operated in the Punjab, consuming enormous fuel and
energy
• Government is heavily subsidizing electric tariff for agricultural
tubewells putting additional burden on national exchequer
• Agricultural production through irrigation with electric tubewells is hit
badly by energy crises as the grid electricity in remote areas is
extremely short
• The replacement of existing non-renewable energy source of fossil fuels
for irrigation tubewells with renewable energy resources such as solar
or wind is a viable option

SOLAR TECHNOLOGY
• When light falls on the active surface, the electrons in a
solar cell become energized and Photovoltaic array
converts solar energy directly into electricity as DC
• The power from a solar system and the volume of water
pumped varies with the amount of solar radiation
• The pump will have its own optimum discharge
depending on the type and size of panel/ motor

COMPONENTS OF SOLAR WATER PUMP
Photovoltaic pumps are consist up of three main
components
Power Source
Photovoltaic solar module
Motor (AC/ DC) & Pump
Submersible
Centrifugal
Power Controllers
Inverter
Maximum Power Point Tracker

POWER SOURCE (PHOTOVOLTAIC MODULE)

SUBMERSIBLE PUMP

INVERTOR

METHODOLOGY
• When the Photovoltaic (PV) module (array) is exposed to
sunlight and light falls on the active surface, the electrons in
a solar cell become energized and Photovoltaic array
converts solar energy directly into electricity as Direct
Current DC
• The Photovoltaic PV module can also be used for AC
applications using an inverter. Photovoltaic 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 power from a solar system and the volume of water
pumped varies with the amount of solar radiation

WORKING OF SOLAR WATER PUMP
The system mainly consists of PV
array, inverter, controller, submersible pump and water tank.
• A photovoltaic array is use to collect solar radiation and converts
directly into electricity as DC and then into AC through Inverter
• The pump will have an electric motor to drive it and use to transfer of
fluid
• An appropriate water tank to store water for later use.
• Stands for the PV array has the tracking function (by manual
regulating the stands), significantly increasing the working time of the
system to pump more water.

SOLAR WATER PUMP

INSTALLATION OF SOLAR WATER PUMP

BORING FOR SOLAR WATER PUMP

FOUNDATION FOR STANDS

INSTALLATION OF PANEL

PILOT TESTING OF SOLAR WATER
PUMPS

PROJECT DIGEST
Name of the Project
• PILOT TESTING OF SOLAR WATER PUMPS
Location
• The project will be implemented through out the Punjab province by
installing nine (9) Solar Water Pumps at selected government farms.
Sponsoring
• Government of the Punjab through Agriculture Department
Execution
• The Punjab Agriculture Department through Directorate General
Agriculture (Water Management) Punjab, Lahore
o Supply & Services Companies
Project Period
• 2009-10 to 2011-12
Project Cost
• 19.22 million

PROJECT OBJECTIVES
The main objectives of the project include, interalia, the
followings
• Assess the effects of solar radiation (insolation) on solar array
outputs and subsequent variations in pumpage at various
locations around the province.
• Evaluate the performance of different types of solar energy
arrays (fixed & moving) over extended periods of time under
different agro-climatic conditions as the rated specifications
given by manufacturers generally reflect peak performances
under ideal conditions and do not accurately indicate long term
performance under less than ideal or poor conditions.
• Compare manufacturer’s specifications under less than ideal or
poor conditions.

PROJECT OBJECTIVES
• Compare manufacturer’s specifications under less than ideal or poor
conditions.
• Find out pros and cons of using fixed array systems having lower cost and
better stability but lower efficiency, versus solar tracking arrays which
have higher efficiencies but are more expensive and difficult to maintain.
• Integration of solar energy pumping units with different high efficiency
irrigation systems such as drip, trickle, gated pipes etc.
• Determine the most optimum configuration, in terms of
efficiency, economic viability and reliability.
• Develop most optimum cropping patterns (year round) which offer
maximum returns to investments in solar energy pumping systems.

PROJECT COMPONENTS
The main components envisaged for proposed scheme
include, interalia, the followings.
• Installation of 9 Solar Water Pumps at selected government farms in
the province
• Construction of water storage tank
• Data collection of each site and its compilation
• Training / Capacity building of the operator (Field Assistant) in
operation, maintenance, and management of solar water pumps
Contd…

Advantages
• No fuel requirement for operation
• A little maintenance
• Environmentally benign
• Long panel life (15-20 years)
Limitations
• High initial capital cost
• Uses unfamiliar technology
o DC motors
o Submersible pumps
o Alternator/ batteries for operating AC motors
• Difficulty for arranging repair / spare parts
• Susceptible to theft and vandalism

SELECTION CRITERIA
The government farm
following criteria
were selected primarily on basis of
• Water of the farm is fit for irrigation
• Provide 4 acres cultivated (preferably fertile, not barren/virgin) piece
of land free of cost for project activities
• Preferably shallow watertable
• Preference will be given to the farm where high efficiency irrigation
system has already been installed
Contd…

BASIC INFORMATION OF SITE AT SHEIKHUPURA
Sr.
No
Particular
1 GPS Coordinates
Description
N 31 42.541’
E 73 57.971’
2 Water table Depth (Meters) 20
3 Water Quality Good
4 Existing Crops
Vegetables & Crops (Tomato,
Wheat, Rice)
5 Crop to be Grown (Wheat, Vegetables )
6 Current Irrigation Method Conventional (Furrow Irrigation)
7 Proposed Irrigation Method Furrow & Flood Irrigation
8 Soil Type Clay loam

EFFECT OF GROUND WATER TABLE (H) ON DISCHARGE
AT CONSTANT POWER
Head
Power
2KW 3KW 4KW
H1 (25 ft) 14 17 22.667
H2 (45 ft) 10 14 17.667
H3 (65 ft) 7.333 9.667 14
Discharge in LPS

Discharge and Head

Relationship of Discharge with Duration

Relationship of Discharge with Duration

Discharge Difference among different districts

SUMMARY
• The increasing fuel prices day by day and depletion of fossil fuel
reserves is making a question mark on the reliability of diesel
operated water pumping systems.
• The shortfall of electricity in Pakistan and the decreasing capacity of
current water storage reservoirs is also an alarming sign which forces
the farmers to look for alternatives of the conventional water pumping
options.
• The sun shine hours are abundant enough throughout the year in
Pakistan; therefore, solar water pumping is a reliable option for remote
areas.
• The 1.8 KW solar water pumping system is adequate for generating an
optimum flow rate for 3-4 acre and will be more effective if use with
drip irrigation

Thanks