Solar Rainwater Transfer Pump - Part 1

Other Videos in this series:
Solar Rainwater Transfer Pump - Part 1 • Solar Rainwater Transf...
Solar Rainwater Transfer Pump - Part 2 • Solar Rainwater Transf...
Solar Rainwater Transfer Pump - Part 3 • Solar Rainwater Transf...
Solar Rainwater Transfer Pump - Part 4 • Solar Rainwater Transf...
Solar Rainwater Transfer Pump - Part 5 • Solar Rainwater Transf...
We use three low-cost high durability 24VDC micro brushless DC pumps plumbed in series to achieve 75ft of head at 3.5 gallons per minute. The pump system transfers rainwater from a 5,000 gallon water storage tank at the bottom of the property to an 1,100 gallon storage tank at the top of the property. The system runs directly off a solar panel without a battery or charge controller. Transfer to the upper tank allows for gravity irrigation anytime day or night.
We are using a single 250Watt 60-cell PV panel to power the pump system. Each of the three pumps draws a max power of 48Watts, for a total max power draw of 144 Watts for the combined three-pump system. Each pump is designed for a max head of 36ft, but with the three pumps plumbed in series, the system should in theory be capable of a max head of 108ft. We demonstrate this system is capable of delivering about 3.5 gallons per minute at 75 ft of head.
Our total pipe run from the lower tank to the upper tank is about 500 ft of 3/4inch poly pipe (SIDR15) with a total elevation change (static head) of 75ft. The gravity head from the upper storage tank provides gravity-flow pressure to all my outlets down below at pressures ranging from 25-30psi (depending on elevation in the landscape).
The system is automated using a custom built pump controller that integrates two Reed-type float switches, a low level float switch in the bottom tank that shuts the pump off if the lower tank empties, and a high level float switch in the upper tank that shuts the pump off when the upper tank is full. The float switch circuit also includes a manual toggle switch and a digital timer. The circuit activates a 24V automotive relay that switches power to the pump system.
Pumps:
Topsflo TL-C01-D24-2211 /S /PV
Specs can be found here: www.topsflo.co...
Pumps available for purchase here: www.ussolarpum...