Choosing a Solar Powered Water Pump for well, pond or swimming pool applications. What you should know before buying solar powered pumps and which is the best solar powered water pump for your purpose.
Solar powered pumps offer an excellent alternative for applications that only need to run for a few hours a day. A great substitute for generators, eliminating the need for buying, transporting and burning depleting fuel sources.
Solar water pumps run on DC or 12 volt energy. Solar panels make DC energy so can be hooked up directly to the pump. When the sun shines, the pump works... when the sun doesn't shine, the pump doesn't work. This direct connection between pump and panel eliminates the need for batteries, making it a low maintenance system.Water tanks, cisterns or troughs need just a few hours of water pumping per day to keep them topped up, making a solar powered water pump an ideal choice for the job. Solar pumps function at full power for around 4 to 6 hours on a sunny day or at a lower volume during overcast days or when intermittent cloud temporarily obscures the sunlight.
It's important to match the pump and panel to ensure that the pump is adequately powered for it's size. The addition of a charge controller may be advisable to prevent pump damage.
You can turn almost any pump into a solar powered water pump but - and this is a big but... pumps that are designed specifically to run on solar power are very energy efficient. That translates into, cost efficient, even though initially, they'll cost more. The bigger the pump the more watts of solar panel you'll need in order to power it.
Conventional 110 volt AC model pumps are inefficient and require so much energy to start and run that they are impractical to use with solar panels. If you are going to use an AC pump, buy the most efficient model available and keep this in mind. You'll require the addition of an inverter that can be quite a power hog by itself. You can't use DC power to run an AC pump. (The inverter changes the power to AC to make it compatible with the pump). That means you'll need more wattage to power the pump than if you use a solar power water pump.
While DC (12V) pumps are super economical when it comes to power use, they're not exactly over achievers in the flow rate department. (where an AC pump offers a gush, a DC pump makes do with flow) That doesn't mean they don't get the job done, they're just a little more relaxed about it.
In order to make the best selection of the available solar pumps you should know:
All of the above information will have an impact on your choice of solar powered water pump. As with any system, the simpler it is and the fewer components attached to it, the easier it will be to maintain and the lower the cost will be.
However, there are components that can, and in some cases should, be added to your pumping station to increase your energy production or otherwise enhance your system.
Without a battery, solar powered pumps will work as long as the sun strikes the solar panel. When the sun shines brightly and is directly overhead, the pump will work to it's optimum ability (given that the panel is sized correctly for the pump). If a cloud passes overhead and temporarily blocks the sun from the panel, the pump will either slow down or stop completely.
Fortunately, for most solar powered water pump applications that's more than enough water pumping time to get the job done.
Aside from being expensive (often costing more than the rest of the system) and requiring more maintenance than any other component of your solar pumping station, the addition of batteries reduces the flow rate of the pump by decreasing the operating voltage.
Also, batteries need to be sheltered and they function best when maintained at certain temperature levels. Both freezing and high temperatures can cause irrepairable damage to a battery, and no matter how well you maintain your batteries they will probably have to be replaced every 5 years or so.
That said, batteries are the component that make solar pumps run on demand 24 hours a day. Without the storage capacity of batteries, solar energy is only available during the day.When using a solar power pump for necessary operations or where seasonal fluctuations of sunlight hours will affect active pumping time, a battery backup or other source of energy should be considered to ensure the uninterrupted function of critical operations .
~ KIDS SOLAR PUMPS ~
Here's a fun experiment you can try with your kids using solar water pumps and solar panels. It works great with a solar pond fountain.
Have the kids stand between the panel and pump (so their shadow falls on the solar panel) when the pump is working. Watch how the shadow causes the pump to slow down, or even stop. Move away from the panel and watch the fountain start up again.
To compensate for overcast days (when the system will pump water at a reduced volume per hour), size your system to pump slightly more water than you need and pump the excess water into an elevated storage tank. This takes advantage of another form of green energy... Gravity. The water in the elevated tank will now be available through a gravity feed system day or night. Think of it as a low maintenance replacement for batteries.
Storing a 3 day surplus of water is usually sufficient for household and livestock needs.
Add a controller for smoother pump performance, low water cut-off features and less damage caused by lightning or running a pump dry. The controller also prevents the pump from trying to operate when the panels are not producing sufficient energy.
Adding a float switch to a controller prevents tanks from over and under filling by switching energy flow off and on when the water level in the tank reaches certain levels.