| ar water pumping system uses solar energy to | | | | readily available. Recent fuel price increases and |
| pump water. | | | | generally intensive maintenance schedules |
| Parts | | | | however can make diesel water pumps a costly |
| Solar PV panel | | | | pumping option. |
| One of the following motor-pump sets | | | | Solar water pumps are often thought of as being |
| compatible with the photovoltaic array: | | | | an expensive technology, which is not able to |
| surface mounted centrifugal pump set, | | | | pump enough water and which is not durable. |
| submersible pump set, | | | | However, solar water pumps have come a long |
| floating pump set, | | | | way in 25 years and today there are solar pumps |
| Submersible pump set, | | | | on the market which have improved on previous |
| Any other type of motor-pump set, after | | | | technology. |
| approval from MNRE. | | | | 1: Submersible pumps which can pump up to |
| Pipes | | | | 200m heads; |
| Working of a solar water pumping system | | | | 2: Pumps that are able to pump larger volumes of |
| The system operates on power generated using | | | | water, e.g.: |
| solar PV (Solar Photo Voltaic Module) system. The | | | | At 100m, about 10,000 liters per day; |
| photovoltaic array converts the solar energy into | | | | At 50m, about 20,000 liters per day; |
| electricity, which is used for running the motor | | | | Above performance can be doubled through dual |
| pump set. The pumping system draws water | | | | systems (if the borehole allows his). |
| from the open well, bore well, stream, pond, canal | | | | 3: Low maintenance requirements (3 to 5 years). |
| etc. | | | | 4: Good performance which means fewer solar |
| The system requires a shadow-free area for | | | | panels to pump the same amount of Water. |
| installation of the Solar Panel. | | | | 5: Some of the pump models can be backed-up |
| Utility | | | | by a genset to pump additional water with the |
| A system with 1800 watt PV array capacity and | | | | same pump during the night or during overcast |
| 2 HP pump can give a water discharge of 1.4 lakh | | | | days; |
| liters per day from a depth of 6 to 7 meters. | | | | 6: Good quality and reliability. |
| This quantity of water is considered adequate for | | | | 7: Simple to install: Furthermore, solar pumps are |
| irrigating about 5-8 acres of land holding for | | | | well known for having the following features: |
| several crops. | | | | 8: Require minimal attention as they are |
| Approximate Cost | | | | self-starting; |
| Total cost of the system - Rs. 2,90,000/- | | | | 9: Solar pumps are good for boreholes as |
| GOI subsidy through MNRE - Rs. 1,80,000/- | | | | they pump over the whole day; |
| Advantages | | | | 10: Weak boreholes can be used effectively with |
| No fuel cost - as it uses available free sun | | | | a low volume pump due to pumping 8 to |
| light | | | | 10 hours a day; |
| No electricity required | | | | 11: In most cases, a solar pump offers an ideal |
| Long operating life | | | | solution to the diesel option which requires |
| Highly reliable and durable | | | | operating funds (with uncertainty about future |
| Easy to operate and maintain | | | | diesel prices), time investment for operating pump |
| Eco-friendly | | | | (manual starting etc) and logistics for fuel, |
| Traditionally the water pumping technology of | | | | maintenance, installation and de-installation; |
| choice has been the wind pump. Wind pumps | | | | 12: Tracking arrays can be used to increase daily |
| provide long lasting solutions with a basic | | | | water pumping rates; |
| technology which is well understood and can be | | | | 13: Solar pumps offer clean solutions with no |
| maintained locally. However even wind pumps | | | | danger of borehole contamination. |
| have become expensive to install and to replace. | | | | Theft of solar photovoltaic panels is a problem |
| Solar water pumps and dc pumps are currently | | | | and one needs to look at counter measures if |
| being used to irrigate crops, water livestock, and | | | | there is a risk of theft. Refer to web links below |
| provide potable drinking water. Solar water pump | | | | for more information. |
| uses peak solar array output which frequently | | | | Cost of solar and diesel pumps: |
| coincides with high water demand during long, dry | | | | A cost comparison was conducted for solar and |
| summer days. In the event of cloudy weather | | | | diesel water pumps over a range of pumping |
| solar water pump systems often use storage | | | | heads (10 to 200m) and a range of daily flow |
| tanks to store excess water. Unlike generator | | | | rates (3 to 50m3/day). The all-inclusive costs |
| powered water pumping systems, solar water | | | | were calculated taking into account. |
| pumps do not require fuel or constant | | | | The initial upfront cost, the operating costs (diesel |
| maintenance. Solar water pumps can also be | | | | fuel for the operating life), maintenance costs, and |
| designed for portability to be moved as water | | | | replacement costs (diesel engine, solar submersible |
| demand or change of seasons requires. Solar | | | | pump unit etc).Calculating the all-inclusive cost is a |
| water pumps cost less to operate, offer modular | | | | fair way of comparing solar pumps (usually higher |
| capability to be quickly expanded as demand | | | | upfront cost) with a diesel pump (usually lower |
| increases, unlike a generator or windmill water | | | | upfront cost, but with ongoing diesel and intensive |
| pumps. | | | | maintenance costs). The all-inclusive cost takes a |
| Diesel water pumping is attractive due to the | | | | long term approach and is calculated over a |
| large power range of the pumps and the | | | | twenty year period, which is also the minimum life |
| availability of water when it is needed. It can | | | | expectancy of a solar panel. The cost |
| pump water for varying daily demands through | | | | comparisons show that diesel pumps are on |
| longer operating periods (assuming sufficient | | | | average two to four times more expensive over |
| borehole strength), thus allowing for the flexibility | | | | a 20 year period than solar pumps for pumping |
| required in some applications. The technology is | | | | the same average amount of water per day! |
| well understood and service for diesel engines is | | | | |