Uninteruptable Power Supply for Water Pump?

[HerHusband]

Does anyone make a UPS (uninteruptable power supply) powerful enough to run a 1/2 HP - 240V submersible water pump?

We live in a rural area which means we have occasional power outages, usually at the worst times. Unfortunately, when the power goes out, so does our water supply. That means we can't wash up, flush the toilets, or even get a drink of water when the power goes out. We're building a new house that will have a wood stove as a means of backup heating. We could even heat pans of water on the woodstove if we needed to for bathing, dish washing, etc. But, we still need a supply of water that will last a day or two.

I'm not interested in a gas generator as it would seldom be used, would require maintenance, and would require that we hike out to the pump house in the worst weather to start it up. In addition, we have a 250 gallon pressure tank, so the pump really only runs a short time when needed to refill the pressure tank.

So, I'd like to find a system that uses a battery and an inverter to power the pump, with provisions to automatically keep the battery charged up when we do have power. It should be totally self maintaining, no switches to flip, no generators to start, etc. Just like a UPS you would use for a computer, only large enough to run the 240V pump.

Any ideas who would make something like this?

Better yet, is there a way we could add additional pressure tanks or something to ensure that we always have a large supply of water? It always seems like we lose power just as the pressure tank is about empty. So, we rarely ever have the full 250 gallons when the power goes out.

For what it's worth, our pump house is located about 150 feet from our house. The pressure tank and all pump equipment is in the pumphouse, and has it's own power separate from the house.

Thanks,

Anthony

[Bill]

Batteries can go bad and need replacement. Plus you would need quite a few to run a pump. Thus the cost of maintenance would probably be higher than that of a generator in the long term.

I would think a larger capacity pressure tank would be the least expensive in the long run. It would be a one time expense with little or no maintenance. You just need to figure out how much water you use in a day and then remember what the longest outage was, then get a tank which will hold that much water and still have pressure.

[John Hines]

A UPS by design, is about keeping the power on during those short periods, for computers.

You need something that would kick on after a bit, as maybe ten seconds or so, as you don't need that complete uninteruptablity.

I'd suggest a battery backup, with an inverter to power the pump. It would charge off the lines (or maybe solar as well) and would run the pump just fine.

Trace is a provider of inverters. Try one of the solar energy news groups for more information on a setup like this, even if you don't add a solar panel for charging. If you did, it would lower your electric bill.

[<gabriel>]

What you want does not exist. UPS units do go bad, and they not cheap to fix. A properly maintained UPS unit needs the batterioes replaced at least every 2 years. Additionally, the cheapest UPS that will handle 240V would run you about $1000.

Also, the run times are very small. A "big" UPS for a computer can keep the power for about 2 hours, and I am talking about a huge UPS for a PC. Normally a UPS, used at it's rated power can give you about 30 minutes of power when the batteries are new.

Anyway, the setup we use here is that we have all the PCs in the server room attached to UPS units, but we have a generator that kicks in at an outage after about 30 seconds of no power. Even with that setup some computers turned off because of bad batteries.

I would just go for a generator if I were you.

[Mark Jerde]

I don't know if this would work, but it's something to think about.

I've wondered about putting a tank on the 2nd floor of the house. (Like a water heater, but not hooked up to heat the water.) When the power goes off and pressure goes down, ISTM the first floor toilet could get a few flushes, gravity fed, from the 2nd floor storage tank.

I don't know about "water hammer" issues, though.

Any comments are welcome.

-- Mark

[Mark Jerde]

Thanks! Your reply is a keeper!

-- Mark

[<gabriel>]

This is exactly what the third world countries do (except the tank is on the roof). Large cities do not have a good water system, so they "rotate" water pressure around the city. Your house might get water for 8 or 16 hours a day, for example.

These places have one or two reservoirs on top of the house, all the water into the house (and the water heater, etc..) comes from the reservoirs. The rich people have an additional underground reservoir that feeds the reservoirs on the roof through an electric pump (either manually or automatically operated). This is a lot of water that gets stored!

With a properly-designed system (you'd have to hire a 3rd world engineer, but they really have the physics of this down), you can get a decent gravity-pressurized water system. The water pipes have to be sized and routed correctly.

[DT]

Yep, this is what I found in rural Thailand in 1995. The water system ran throughout the country, primarily an exposed 3" pvc pipe alongside the road, and buried very shallow to cross a road. Every house had a single tap connected by a small flexible water line (about 1/2").

People simply used the central water system to refill their existing water containers, which were large, outside pottery jars in the most primitve cases, indoor cement tanks in the moderate homes, and rooftop tanks for homes and businesses that had water pressure.

In most cases, people just left their tap open *all the time*, so flow was reduced to a mere trickle, but that was enough to slowly refill the tanks.

Homes without water pressure used water by dipping from the tanks. A smaller tank was beside the toilet to permit flushing by pouring water down the hole. In the home we stayed in, a small frog lived in the indoor tank, which was about 200 gallons or so. Didn't drink the water, but locals used it for cooking, washing dishes, etc., so a case of intestinal something followed me home despite my being careful.

DT

[gabriel]

LOL! Yeah, you gotta build up a stomach to not get sick. It really helps if you boil the water before drinking, but you really cannot get away from it unless you also cook for yourself, and then cook everything thoroughly.

The reservoirs are getting better in places like Mexico, where they have been coming out with sealed reservoirs for the past 5-10 years. It really makes a difference in the cleanliness of the water.

I can't help but remember when I opened the tap in Mexico one day and a large-ish (6-8 inch) red-orange centipede came out right before i put my hands in to wash them. To this day, I do not know who was more scared, the centipede or I!