Solar water pumps enable you to move water from its remote source to where you need it, without access to power lines. Solar pumping has three primary uses; domestic use for washing, cooking and drinking, livestock watering, and irrigation. The same basics are used for all three requirements, although domestic use may require additional capabilities. We’ll discuss domestic use for this blog. We’ll cover irrigation and livestock in a future blog post. Solar water pumps are different from regular AC powered pumps in more ways than the simple fact that they use DC power instead of AC. Most solar pumps are designed to be used in off-grid situations, and are designed to be extremely efficient. By not experiencing losses when going from DC to AC and back to DC, you can maximize your pumping while minimizing your power use. The most efficient way to use a solar pump is PV-direct, powering the pump directly off the solar panels, without using batteries. Rather than experiencing losses through storing power in batteries, the water itself is stored in a cistern or tank to be used when needed. It’s much easier to store water than power. The difference between a cistern and a tank is a cistern has a removable lid, and a tank is generally sealed.
SUBMERSIBLE SOLAR PUMPS VS SURFACE PUMPS
Solar water pumps are typically divided into two categories:submersible pump and surface pump. A submersible pump is installed under water, usually in a well, but can also be in a pond or stream if raised off the bottom. A surface pump is installed above the water, with an intake hose feeding the pump from the water source, and the output hose feeding the tank. Pumps are able to push water out much higher than they are able to suck water in, so the they need to be close to the water source. Keep the head, or the height difference between the water and the pump,as low as possible.
Most of us need a boost to get going in the morning; a solar pump is no different. Pumps generally require a high surge in current when starting up, but not a lot of voltage. As a result, when solar pumps are starting in the dim, morning light, it can sometimes have trouble
getting started. LCB is a device that can be installed between the solar panel array and the pump to increase the current output to get the pump going in lower light. It does so by dropping the voltage output, which doesn’t affect the water flow as much as current does. This will allow pumping to begin earlier in the day, and continue later in the afternoon as the sun is heading down – giving you more water pumped overall during the day.