Solar Water Pumping

If you need to supply water beyond the reach of power lines, then solar power can solve the problem. Solar water pumps and dc pumps are currently being used to irrigate crops, water livestock, and provide potable drinking water. A solar water pump operates during the day which coincides with high water demand during long, dry summer days. Solar water pump systems often use storage tanks to store excess water, which can help during cloudy weather.

Solar water pumps cost less to operate, offer modular capability to be quickly expanded as demand increases, unlike a generator or windmill water pumps.

SOLAR WATER PUMP SYSTEMS QUALIFY FOR 30% FEDERAL TAX CREDITS!!

Typical solar water pump applications:

* Irrigation (lift and pressurized)
* Livestock (deep wells, pipeline transfer, pond and stream protection)
* Aquaculture (transfer, circulation, aeration, de-icing)
* Camp sites, vacation cabins
* Home and village supply
* Water purification and treatment systems

Solar Trackers- Mounting solar panels on trackers is often a cost-effective method of getting the most out of your solar array and your solar water pumping system. Solar trackers follow the sun during its arc through the sky and boost water pumping by 25 to 40%.

The type of solar water pump you use depends on your application and the configuration of the water source. There are really only two basic types of solar pumps; positive displacement and centrifugal and these can both be subdivided into surface mount and submersible categories. Your water source will dictate whether you need to use a surface mount or submersible pump while your daily volume requirement and total dynamic head (TDH) will determine if you need a positive displacement pump or centrifugal pump. In general, positive displacement pumps (diaphragm, piston, helical rotor, etc.) are best used where the TDH is high and the daily volume requirement is low.
Positive displacement pumps usually require less power to operate than a centrifugal pump and they will produce some water even in cloudy conditions where a centrifugal pump might not. Centrifugal pumps are good in situations where the TDH is low and the daily volume requirement is high. One of the disadvantages of a centrifugal pump is that it has to operate at a high enough rpm to push the water all the way out of the well. If it is cloudy and the solar array is not producing enough power, the pump/motor may be turning but not fast enough to do this. Using a tracker is highly recommended with a centrifugal pump since it increases the solar array's power output over a longer period of time which increases your daily volume of water delivered.

A surface pump is one that is mounted at ground level. Surface pumps work well when they draw water through suction less than 10 or 20 feet. A submersible pump is one that is lowered into the water. Most deep wells use submersible pumps. Submersible solar pumps are used for low to medium lift wells where high flow capacity is required. Pressurized/Booster Pumps are used where surface water or shallow well water is available that must be pressurized for domestic water use.

A pump controller (current booster) is an electronic device used with most solar pumps. It acts like an automatic transmission, helping the pump to start and keeps it from stalling in weak sunlight.

Sizing solar pumps
The hydraulic energy required (kWh/day)
= volume required (m³/day) x head (m) x water density x gravity / (3.6 x 106)
= 0.002725 x volume (m³/day) x head (m)

The solar array power required (kWp) =
Hydraulic energy required (kWh/day)
Av. daily solar irradiation (kWh/m²/day x F x E)
where F = array mismatch factor = 0.85 on average
and E = daily subsystem efficiency = 0.25 - 0.40 typically