Water pumping
If You live in a place with city supplied water you are isolated from the realities of how much energy it takes to supply you with all that convenient water. Most cities in the southwest pump water for many miles and in many cases over mountains to reach you. every gallon of water you consume requires energy, usually in the form of a very large electric powered pumping station. the cost of this energy and infrastructure is partly hidden in the form of taxes. saving water saves energy, period. do your part by conserving, no matter where the water is coming from.
In an off grid home, you will be very close to the realities of moving water and there are several ways to do it that will make it as easy on the batteries and as foolproof as possible.
water pumping can be achieved by generator power if you have an uphill storage tank providing pressure. Running a generator for 10 minutes so a gravity tank can be topped off would be the ideal way to go if you can manage it. Solar could take over the job later. I have plans to run an underground water line up to the top of my property and then move the tank up there so that it will not require the pressure pump that i am now using.
The pressure pump that i use right now is actually two 24 volt DC powered pumps wired and plumbed in parallel. these pumps are meant for RV’s or boats. 24 volts is far more efficient than 12 volts and most larger RV’s and boats use it. Nearly all military vehicles and aircraft are 24 volts as well. Those of you old enough can remember the old 6 volt car batteries and what a huge improvement 12 volts made. 24 is a bigger jump yet for the better.
the two pumps together can provide about 3 gallons per minute, lifting about 30 ft in the process and the pressure is set to 40 psi. If You are wise, you will get a large (40 gallon or more) pressure tank, a seperate pressure switch that has a on and off setting.. most have only one adjustment screw that moves both points up or down.. not as good as the fully adjustable version. the larger the tank, the narrower the on-off range can be. this allows for a small pump to provide big gulps of water and the pressure will be more consistant.
12 Volt RV pumps are available locally that can provide 30-35 PSI and 3 gallons a minute. 24 volt pressure pumps are found online (i have about a dozen for sale myself)
There are various types of DC powered pumps that can run directly from solar panels that will keep your tanks topped off. I have seen pumps that can lift water from over 300 feet deep using 24 volts supplied from two 75 watt panels. A friend of mine has a 500 ft deep well and uses a 300 watt array to supply water. He has 10000 gallons in the tanks and it is always full.
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