Solar Water Pump
our main concentration to present high efficient Solar water Pump at low cost.

Solution

OBJECTIVE:

The  main objective of  our project is to Design and Fabricate a Solar Water Pump so that our Indian farmers can utilize it at affordable cost.

METHODOLOGY:

Initially we have designed the circuit diagram for installing the solar pump, the circuit diagram is as follows, as we are aware that solar panels never gives us a constant voltage i.e, output at 100 % instead it gives an a variable voltage, to over come this problem we are planning for an "Charge controller".

The pump controller protects the pump from high- or low-voltage conditions and maximizes the amount of water pumped in less than ideal light conditions. An AC pump requires an inverter, an electronic component that converts DC electricity from the solar panels into AC electricity to operate the pump.

DESCRIPTION:

From the above circuit diagram a solar panel of 250 watts is connected to a rechargeable battery and this is connected to a water pump. After the purchase of solar panel, a battery or inverter and a pump set along with remaining equipment the installation is done. and it is portable too with minimum transportation charges. the setup can be protected from theft by providing casing to battery and charge controller. The array setup can be fixed at a place by providing a stand.

specification:

250 watt solar panel made of Taiwan high efficiency and quality solar cells.
Made by Taiwan high quality poly crystalline cells
Peak power Output WP (W): 250Wp
Best voltage Vmp (V):29.4V
Best electric current Imp (A):8.5A
Short Circuit electric current Isc (A):9.2A
Open Circuit Voltage Voc (V):36.3V
Dimension (mm):1640×990×50
Weight (kg):18KG
Impact Resistance Hail impact Test: 227g steel ball down from 1m height
Maximum system voltage:e1000V
Quality guarantee: nominal power keep more than 90% in 10 year and 80% in 25 years.

Exclusively we are choosing an Poly crystalline panels, not thin film solar panels due to its efficiency.

Nowadays most of the solar cells are made of mono crystalline and multi crystalline silicon.
Silicon ingots are fabricated by using some crystal growth processed like CZOCHORALSKI method by using some special purpose furnaces and other instruments used in the process.
These intrinsic semi conductor silicon wafers are then converted into extrinsic semiconductor .
Si wafers can be made for higher mobility by adding some n type(phosphorus) and p type (boron) impurities and to have a P-N junction.
The efficiency of this type of cells is much higher (15-20 %).

For getting efficient input we need to start from basics, i.e, tiltation angle, once we get required voltage then we can opt for varieties of pumping sets like DC submersible pumping sets, or DC centrifugal pump of lower H.P like 2 hp or 1.5 hp, which gush enough water from surface as well from storage tanks of 5m head.

Let me explain, how we gonna calculate the tiltation angle. as you have seen from my pic of tilted panel with angles mentioned.

ALTITUDE ANGLE (α) : IT IS THE VERTICAL ANGLE BETWEEN THE DIRECTION OF SUN RAYS AND ITS PROJECTIONS ON THE HORIZONTAL PLANE.
ZENITH ANGLE (θz) : IT IS THE VERTICAL ANGLE BETWEEN THE SUN RAYS AND THE LINE PERPENDICULAR TO THE HORIZONTAL PLANE TO THE POINT .
θz = α+γ = π/2
SURFACE AZIMUTH ANGLE (γ) : IT IS THE ANGLE MADE ON THE HORIZONTAL PLANE OF THE NORMAL TO THE SURFACE ON THE HORIZONTAL PLANE.
SLOPE (β): THE ANGLE MADE BY THE PLANE SURFACE WITH A HORIZONTAL SURFACE.THE ANGLE IS TAKEN AS POSITIVE FOR A SURFACE SLOPING TOWARDS SOUTH , AND NEGATIVE FOR A SURFACE SLOPING TOWARDS NORTH.

with these angles, we can use, to compute the beam energy falling on a surface having any orientation,the incident beam flux "Ib"multiplied by COSθ where θ is the angle between the incident beam and normal to the tilted surface and the angle θ depends on the position of the sun in the sky. tilted angle computation is shown in the slide.

as sun is also not at one place, we can opt for an tracking mechanism, by providing servo motors, which rotates or tilts the panel as sun moves at slower pace as sun dawns. so that there would be no variation in pumping of water.

Pump sets:
There is considerable commercial interest in manufacturing photo voltaic powered pumping sets.  The power output of the system is directly proportional to the number of solar cells and the surface area of the panel exposed to the sun.  The discharge of a solar pump with array area of 2-4m varies from 6-8 lits/s at a head of 5 m.  This could irrigate about 1.5 - 2 ha of land with crops having moderate irrigation requirements or may provide protective irrigation to even a larger command.

Calculation of Pumping Head:

Pumping head is normally measured in meter (m)
 In actual, pumping head is divided into three components: elevation head, major losses head, and minor losses head. 
Pumping Head (m) = Elevation Head (m) + Major Losses Head (m) + Minor Losses Head (m) 
Elevation head is measured from the water source surface level to the point of outlet pipe level. 
Major losses head is influenced by water flow rate, diameter of pipe, length of pipe, and type of pipe (PVC, HDPE etc) 
Minor losses head is influenced by piping accessories including valve, elbow, inlet pipe etc 

MAINTENANCE OF SPV SYSTEM:

The supplier provides annual maintenance contract to the beneficiary at Rs. 1950/- after initial guarantee period of 1 1/2 years. The solar panel is expected to provide about 20 years of satisfactory service under normal conditions, even though the cell itself may last much longer.  The only maintenance requirement is occasional washing of the surface to maintain maximum optical transmission through the glass. The panel has to be protected from breakage by external agencies.  Some manufacturers cover the cell/array with unbreakable glass.  The motor and the pump require the usual periodic maintenance like cleaning, lubrication and replacement of worn parts.

ADVANTAGES OF SPV PUMPING SYSTEM:

Cost effective: The life cycle and the cost to ultimate beneficiary make the SPV systems cost effective as compared to conventional systems. IN addition the farmer is saved from the capital investment he has to make for drawing lines from the grid to his field/farms.The govt. may save huge resources which otherwise may be uneconomical to network every agriculture field under the state electricity grid.

BENEFITS TO FARMERS 

Farmer gets a high value, high discharge pumping system for a one time amount that is less than a third of the actual price and may be maintained at nominal cost annually.
1.No fuel costs & minimal maintenance costs. 
2.More economical than diesel pump sets in the long run. 
3..Enables cultivation of an extra crop 
4.Helps in providing the critical protective irrigation in water scarce areas. 
5.Saves time and labor 
6.Improves agriculture productivity 
7.Improves general quality of life with higher levels of income 
8.Incremental income enables easy repayment loan taken for installing system 


conclusions:
Solar water pump that we develop can run satisfactory at all conditions and during peak summer this is the best option which can work out well and it can be easily installed in our campus garden and sump .
However the wattage of solar panel used should be increased for higher performance.