I have two windmills that are powered by solar energy, pumping around 5-7 gallons per minute during sunny times. However, they stop working at night or on cloudy days. I want to set up a system that allows these wells to run continuously, particularly for keeping my livestock tanks full and handling some irrigation needs. What battery solutions are available that would enable me to operate these pumps for about 12 hours a day when the sun isn't shining?
2 Answers
How much solar wattage do you currently have? This upgrade isn't going to be cheap! To power both pumps at night, you'd need about 600 Ah of lithium batteries or 900 Ah if you're opting for lead-acid. Also, to ensure they’re all charged through the night and can run during the day, around 6500 watts of solar panels would be necessary. I recommend the Victron SmartSolar MPPT 150/70 as a charge controller.
One option you might consider is using an elevated water tank, especially if you can manage with low pressure. It's definitely possible to use chemical batteries too, but you’ll need a programmable charger controller that can handle your pumps, plus do some calculations to determine the battery capacity you need. Just remember, you might have to expand your solar array since it'll need to charge the batteries while running the pumps. Just a heads up, running them all night could drain a lot of power!
If you have a downhill area, you could also set up a hydraulic ram. That way, you wouldn't need electricity at all for irrigation! Plus, a water tank could end up being more cost-effective than a bunch of batteries.
I’m confused about how the pump fills a tank during the day if it's constantly running to keep the pond full. Can someone clarify?
So, if I get 6x 100ah lithium batteries and the right charge controller along with extra solar panels, I could keep the well pumps running at night?