Selecting the Solar Pump
Submersible Solar Pumps can lift up to 650 feet and fit in a 4″ or larger well casing and are used when the water supply is deeper than 20 feet from the surface. Submersible solar pumps can operate directly off solar panels, batteries, or in some cases, an AC power source. Water is usually pumped during the day when the sun is shining and stored in a cistern or tank for use whenever needed. It is recommended that several days worth of water is stored to be prepared for stretches of bad weather when no water is pumped.
Surface Solar Pumps are good for applications with shallow wells, ponds, streams or storage tanks. They are best if the water supply is 20 feet or less from the surface. While surface pumps generally can’t lift water very high from a deep source, they can then push water great distances, 200 feet or more!
Linear Current Boosters for Solar Pumps (LCBs) allow the pump motor to run longer during the day by translating additional voltage to necessary current during periods of low sun.
In addition to increasing the current output to allow for longer pumping days like an LCB, a pump controller may also have features like a connection for a float switch to turn the pump on or off based on water level, on/off switch, over-current and/or over-voltage protection, and more.
We also offer Pump Accessories such as filters, valves, and strainers, as well as dry run, float switches and more! Some pumps are more susceptible to damage when run dry or pumping particles, be sure to read the manual to determine if extra protection is required with dry switches or filters and strainers.
Selecting the Solar Panels
The solar panels powering the solar water pump are sold separately. Each manufacturer provides a graph or table showing how many watts or amps and volts of solar panels are needed to produce the desired water flow and/or lift. Once you have selected the appropriate type and size of solar pump, use that graph to calculate the correct watts of solar panels.
The solar pump and the amount of solar panels needed both depend on how many gallons per day (GPD) or gallons per minute (GPM) you want to pump and the vertical head the pump needs to overcome.
Should I use batteries with my solar water pumping system?
Most solar water pumps run directly off solar panels (PV direct) and do not require batteries. Using batteries may complicate an otherwise straight forward application. Instead of storing electricity in batteries to run the solar pump at non-sunny times, most people prefer to store the water in a holding tank. This results in the same effect, water when you need it, with less cost and less complexity. The exception is when you are using a booster pump to create water pressure in your house. Since you may need to boost the pressure at night or on rainy days, batteries are required to provide power whenever pressure is needed.