Water pumping options

levsmithlevsmith Solar Expert Posts: 56 ✭✭
Alright everyone, I need some opinions. I am getting closer to acquiring my land and am trying to get the water pumping figured out. The plan is to build something livable on that land as cheap is I can so that I can get moved in and sell my current house. I will be completely off grid so that is what makes the decision difficult. Up until now, I have been thinking I would do something like most of the ranchers do around here for their cattle, get a tank and pump into it during the day using solar power, a cistern basically. But not having any experience with solar so far, I don't know what kind of performance I can expect during the winter weather with one 260 watt panel. The last thing I want is to not have enough water.

So now I am wondering if maybe I should just go with the standard ac pump run from my inverter. I guess the problem I am having with that is that I only have a xantrex sw2000 12v 2000 watt pure sine wave inverter right now (a regular plug in style, not one that can be wired to a breaker box) and probably wont have the funds to upgrade until I get my current house sold. Speaking of the inverter, like I said, it just has the regular 2 plugs and underneath it says 16.6 amps. Does that mean if I only use one plug, say for the well pump, it can supply 16.6 amps to that single plug, or is the 16.6 split between the 2 all the time (8.3amps each). I also do not understand the sizing on the grundfos sq pumps. From what I have seen with the future neighbors the wells are usually about 80-90 ft deep with a static water level around 30ft. I am assuming for instance the Grundfos 10SQ05-110 would work in my situation, 10gpm at 110ft head and 120v. What I am unsure of is the power draw. The only thing I've been able to find shows power input: 1.09kw and rated current 12amps. I am assuming since these have a soft start feature, there is no surge current? So is the highest I could expect to see 1440 watts (12amps * 120 volts) or 1090 watts (1.09kw)? I am leaning towards this option since I will probably have a 1kw solar system for the house to begin with but I am unsure what would be the best way to go in my situation.

Just from my quick calculations, if I did the solar pump I am looking at about $1233 for the well pump, pump controller, 12v house pump and water storage tank. If I did the conventional AC pump, I am looking at about $875 for the pump, pressure tank, and pressure switch. Just not sure if I'll have the inverter power that I need for the AC pump. Also if need be, I wouldn't mind spending a few bucks on a cheap modified sine wave inverter to add to the system for my other non critical loads if I need to use the 2000 watt just for the water pump.

Thanks for all opinions
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Comments

  • waynefromnscanadawaynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Hi Levsmith, Couple of things - - do we assume you already have a well? How far down is the water level, I know you mentioned 110 feet, but will it stay there when you start pumping? Has any flow rate tests been done on the well? Do you live in an arid location where the underground water source is being depleted by constant pumping, resulting in the water table dropping lower every year? Some underground sources can be depleted by pumps a hundred miles away, as is happening in Cal.
    Now to the single 260 watt solar panel. This will do very little in the way of supplying your needs. There is no way it could ever supply the pumps you're mentioning.
    With good sun and the normal system losses, you could be looking at trying to run a 1100 watt pump with just 200 watts. That's a no go.
  • Texas WellmanTexas Wellman Solar Expert Posts: 153 ✭✭
    Do yourself a favor. Spend the money now and get a Grundfos SQF and then don't worry how you're going to power it. Got an inverter? It will run. Got 30V DC? It will run. Got 300 VDC? It will run. Got grid power? It will run.

    Forget the two tank configuration, you're just pumping the same water twice. Get one big pressure tank and a couple of batteries to keep the pressure topped off if you happen to use some at night.

    You'll thank me later.
  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    Hi Levsmith, Couple of things - - do we assume you already have a well? How far down is the water level, I know you mentioned 110 feet, but will it stay there when you start pumping? Has any flow rate tests been done on the well? Do you live in an arid location where the underground water source is being depleted by constant pumping, resulting in the water table dropping lower every year? Some underground sources can be depleted by pumps a hundred miles away, as is happening in Cal.
    Now to the single 260 watt solar panel. This will do very little in the way of supplying your needs. There is no way it could ever supply the pumps you're mentioning.
    With good sun and the normal system losses, you could be looking at trying to run a 1100 watt pump with just 200 watts. That's a no go.

    Sorry maybe there is some confusion. No I don't have the well yet as I'm still in the process of buying the land. All I can do on the water level right now is guess based off of the neighbors within that mile or so. 80-90ft deep with static water levels around 30ft. Now whether you believe in them or not (personally I'm not sure), the sellers had a well witcher come out before we signed the contract to ease their mind. The well witcher said 70ft with a flow rate of 14gpm. Not in a real arid location, no.

    As far as the 260 watt panel goes, I am talking about using that in conjunction with a sun pumps dc pump. They are designed to run on 12-30 volts direct from the panel while pumping about 1.5gpm using something like 100 watts. That is why I was talking about a cistern with that system. It would pump slowly all day, or however long it needed, to fill up a tank. Then I could have a standard 12v dc transfer pump with a built in pressure regulator to supply the house from that cistern.

    Its either that system or a standard Grundfos AC pump. I wouldn't be trying to run the Grundfos off of a 260 watt panel. If I did the Grundfos instead of the Sun Pumps, it would be tied into my ~1000 watt system running off of the battery bank.
  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    Do yourself a favor. Spend the money now and get a Grundfos SQF and then don't worry how you're going to power it. Got an inverter? It will run. Got 30V DC? It will run. Got 300 VDC? It will run. Got grid power? It will run.

    Forget the two tank configuration, you're just pumping the same water twice. Get one big pressure tank and a couple of batteries to keep the pressure topped off if you happen to use some at night.

    You'll thank me later.

    The Grundfos SQF pumps sound great but the $2000 price tag doesn't right now... As it is, I'm going to be pushing it to be able to afford getting everything put in and built by next summer (2016). If I go over budget, that probably means living in my current house another winter pushing the move in date until spring 2017, which I don't want to do. That is why I mentioned doing things somewhat cheap right now. As long as they last long enough to get my current house sold, then I can start doing things the right way, with decent equipment. As of now, it just needs to work. I know thats probably not a good way to do it because I'll have to buy some things twice, but if I can get out of my current house 6 months earlier, its going to save me about $4500 since the mortgage is $755 a month. So the way I look at it, as long as I'm not spending more than the $4500 on the cheap stuff, its going to save me money.

    Also, maybe theres some confusion on the tanks as well. If I did a Sun Pumps DC pump, I would have a non-pressurized cistern with a separate 12v dc pump with a built in pressure regulator inside the house to pressurize and supply the house lines. If I do a Grundfos AC pump, I will have a standard pressure tank. Either way there is only one tank.
  • mike95490mike95490 Solar Expert Posts: 8,828 ✭✭✭✭✭
    You are going to need a generator anyway, And it's very likely you will quickly outgrow a 12V system and lust for 24 or even 48V Decide now, and you won't have to buy 2 systems. Either way, you need a generator for backup charging. And what I'd do, is get the smallest "240VAC 3wire" pump and a 5Kw genset with 240V output (it will have a couple 120V sockets too) and run the genset to pump water to the main tank, and use the little RV pressure pump for building pressure.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    mike95490 wrote: »
    You are going to need a generator anyway, And it's very likely you will quickly outgrow a 12V system and lust for 24 or even 48V Decide now, and you won't have to buy 2 systems. Either way, you need a generator for backup charging. And what I'd do, is get the smallest "240VAC 3wire" pump and a 5Kw genset with 240V output (it will have a couple 120V sockets too) and run the genset to pump water to the main tank, and use the little RV pressure pump for building pressure.

    Now thats not a bad idea at all, at least to get started. I notice your signature says you have a timer on yours for 3 hour run. Are you pumping into a cistern as well and do you have a thread showing your water setup? I'm curious if you are pumping into a cistern, how do you wire a float switch in to tell the pump to shut off? Is the 3 wire 240VAC pumps the ones that are easier to start, less startup current? And is that 3 wire plus ground?

    And you are right, I'm sure I'll quickly outgrow the 12 volt. But my reasoning to use 12v to begin with is that I already have a 2000w pure sine wave 12v inverter and a 12v battery charger. And when I buy my solar equipment I will be getting an MPPT charge controller. I figure once I get my current house sold, I can take any money I have left from it after paying off the mortgage and buy more panels and batteries. At that time I will probably go ahead and rewire the batteries to 48 volt and spring for a nice 48v 120/240 inverter. That way, the only thing I'll have to purchase now that I wont need after switching to 48v is the little RV pressure pump.

    Thanks for your reply!
  • zonebluezoneblue Solar Expert Posts: 1,218 ✭✭✭✭
    Sure, just remember that the RV pump still needs a small pressure tank, else itll thrash. 12 to 18 litres is usually plenty.
    1.8kWp CSUN, 10kWh AGM, Midnite Classic 150, Outback VFX3024E,
    http://zoneblue.org/cms/page.php?view=off-grid-solar


  • wellbuiltwellbuilt Solar Expert Posts: 476 ✭✭✭
    I bought my land 11/2 years ago , what Ive done so far is to find a free airstream trailer and pull it to the top of the property 3000' up a steep grade .
    We set the trailer facing the south and built a 12x20 deck from trees cut on the hill .
    Added 2 gc battery 210 watts of solar on a 40 amp tracer CC most of the trailer runs on 12v .
    small MS 300 watt inverter for TV , radio , water pumping.
    My water runs off the roof into 2 50 gallon drums , I pump the water thru a filter to clean it up a bit and into the trailer tank 30Gallons .
    30 G last 3/4 days with dishes showers (2/3) .
    We have a good cooler and use 60lb of ice @ 90o temp 14 bucks .
    If the water runs out ? I have springs along the main road that have pvc pipe, that I can hook a hose, small pump 1/4 hp, and a champion 1800watt generator .
    I have a 65gallon tank from tractor supply on my trailer to carry the water on the back of my jeep. The fire dept will fill my tanks or the town pool .
    If the trail up is dry I can get 275 gallons in 2 cube tanks. but my dump is 2wd and its hit or miss getting up .
    Last year we drilled the well to 740' bummer I don't have much water SWL is down 500' I mite get 3 g a min I will have it fracted before I drop the pump down .
    Now I can live on the land and build the house . We spent 4 weeks there and built a 24x 40 garage and foundation for part of the house .
    Next year we build the house 36x36 .
    My pump guy is telling me 10,000 bucks and a 3hp pump , I think I would need a 10000watt generator to run it .
    I may end up off grid so grundfos SQF sounds good to me , Im not sure how I would drop the pump down 700 feet but I will come up with something ?
    If you water is 70 feet down your pump wont cost much just use a generator to fill a 500gallon tank.
    Out back  flex power one  with out back 3648 inverter fm80 charge controler  flex net  mate 16 gc215 battery’s 4425 Watts solar .
  • mike95490mike95490 Solar Expert Posts: 8,828 ✭✭✭✭✭
    I pump 160' from a pond (using a deep well pump in a flow induction sleeve ) to 12,000 gal of storage tanks. The tanks feed my domestic water filter ( a slow sand filter) and gravity feed for 300+ fruit trees, I use about 1,000 gal daily, and have a timer set, with a remote level switch powering a contactor, to energize the pump. So I can go several days without pumping, if need be, and still have pressurized water on hand for fire fighting, In winter, when I don't need to irrigate, I only need to pump 1x a week to keep the feed water for the filter topped off.

    The 3 wire pumps have the motor start cap, in an above ground control box, and they have less starting surge then 2 wire pumps. Ground wire is not counted in the pump wire bundle, and I don't think there is one in the submerged splice.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • ramlouiramloui Solar Expert Posts: 103 ✭✭
    The way I am set up may not be ideal in any way but, depending on the circumstances, it may be a viable option: I pump water from the lake in front of my cabin using a 1½" gasoline pump into a 250 gallon tank on a small hill (20 ft elevation). It takes 10 minutes to fill that tank and I have enough for 1-4 days depending on how many people shower and/or flush the toilet. The lake is about 250 ft from the tank so, when I'm done pumping, I can just wheel the pump to the shed.

    From the 250G tank, it gravity feeds to a 12V RV pump (Shurflo 2088 ) which pressurizes a 20G accumulator tank in the shed. Then it's on to the cabin. This has worked well for me.

    Good luck!

    Off-grid cabin in northern Quebec: 6 x 250 W Conergy panels, FM80, 4 x 6V CR430 in series (24V nominal), Magnum MS4024-PAE
  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    ramloui wrote: »
    The way I am set up may not be ideal in any way but, depending on the circumstances, it may be a viable option: I pump water from the lake in front of my cabin using a 1½" gasoline pump into a 250 gallon tank on a small hill (20 ft elevation). It takes 10 minutes to fill that tank and I have enough for 1-4 days depending on how many people shower and/or flush the toilet. The lake is about 250 ft from the tank so, when I'm done pumping, I can just wheel the pump to the shed.

    From the 250G tank, it gravity feeds to a 12V RV pump (Shurflo 2088 ) which pressurizes a 20G accumulator tank in the shed. Then it's on to the cabin. This has worked well for me.

    Good luck!

    That's great! Sounds like what I am wanting only I'll be pulling from a well since I don't have a lake nearby. And right now, I don't need an ideal setup, I just need something that works.

    One question though, I don't understand what the pressure tank accomplishes when using a 12v rv pump. I am assuming you don't have a pressure switch on the tank. The pump I am looking at keeps a constant pressure of 40 psi. The way I am thinking, it would pump the pressure tank up to 40 psi then shut off. As soon as you turn on a faucet, the pressure tank will drop below that 40 psi and the pump will kick on. Am I missing something here? Why not eliminate the pressure tank and just let it pressurized the lines in the house? Or maybe you DO have a pressure switch on your tank? Please enlighten me!
  • BB.BB. Super Moderators, Administrators Posts: 30,658 admin
    The pressure tank would be setup for something like 20 psi pump turns on, 50 psi pump turns off. A "10 gallon" pressure tank would cycle about 5 gallons of water between cycles (leave room for "air charge").

    You can have a pump without a pressure tank--But if you turn on the faucet 1/2 way--The pump in cycling on/off rapidly (pump is too large and pressure rises to shut point, no storage, as faucet draws down, pump turns on almost immediately to bring pressure back up).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • AguarancherAguarancher Solar Expert Posts: 302 ✭✭✭
    In addition to what Bill said... When using a pressure tank and a pressure switch, the pressure switch is usually a 20psi differential. 20-40, 30-50, 40-60. that way your pump doesn’t cycle every time you open the tap. You will need a simple check valve between the pump and pressure tank as to keep the starting load off the pump. jmo
  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    BB. wrote: »
    The pressure tank would be setup for something like 20 psi pump turns on, 50 psi pump turns off. A "10 gallon" pressure tank would cycle about 5 gallons of water between cycles (leave room for "air charge").

    You can have a pump without a pressure tank--But if you turn on the faucet 1/2 way--The pump in cycling on/off rapidly (pump is too large and pressure rises to shut point, no storage, as faucet draws down, pump turns on almost immediately to bring pressure back up).

    -Bill

    Thanks for the reply Bill! So you would have a pressure switch tied into the 12v motor? I am on well water now so I am somewhat familiar with tanks and switches but I have never wired a pressure switch. I take it you would have your 12 volt wires coming in from the batteries and your 12 volt out to the pump? And do I need a dc pressure switch?

    The rapid cycling makes sense. I have an atv sprayer tank that I use for burning pastures and does exactly what you say. The pump has the capability to pump more than what the spray nozzle can put out so it cycles very rapidly, about 2 times per second when spraying. I'm assuming that's ok for its intended purpose, as it only gets used a couple hours per year but I could see how you wouldn't want one doing that every day.

    Thanks so much for your help!
  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    levsmith wrote: »
    The pump I am looking at keeps a constant pressure of 40 psi.

    Which pump, exactly, are you looking at? You may be correct that you do not need a pressure tank... there are some pumps with variable speed motors that are designed to work without pressure tanks.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Hill_CountryHill_Country Solar Expert Posts: 96 ✭✭
    Hi Levsmith,

    Yet again, we have some similarities!...We're completely off-grid (solar only) and we rely solely on rainwater for our water source. Compared to a well, we're lucky in that our rainwater storage tanks (two polyethylene storage tanks, each one holds 5,000 gallons for a total of 10,000 gallons of storage) are above-ground, so we only have to pressurize the water for household use; no need to pump it "up" from the ground, so to speak.

    For our household water system we have a 24 volt DC Aquatec Series 550 pressure booster pump (factory pre-set to 40psi cut-in/60psi cut-out, 4.5gpm) which is wired to a Square D pressure switch. The Square D pressure switch is manually set to 30 psi cut-in and 50psi cut-out. We also have a 33 gallon pressure tank, which, as several posts have indicated, prevents the pump from coming on and off. Like vtmaps pointed out, if it's a variable speed pump then those are designed to operate without a pressure tank most times. However, if you have a cut-in/cut-out style booster pump then a pressure tank is the way to go. It prevents the pump from cycling, thus saving wear and tear on the pump. We have a tankless hot water system that requires a minimum water pressure of 20psi to work, so we went with 30psi cut-in/50psi cut-out. The nice part is that the Square D pressure switch is easily adjustable via a set-screw, and can handle the DC current of a 24 volt DC pump (max amperage of our 24v DC pump is about 8 amps af full 60psi pressure).

    Hope this helps!
    100% Off-grid with: 8 Solarworld 275 Watt Panels, 8 Concorde SunXtender 405aH 6v AGM Batteries, MS-4448PAE 48v Inverter, MidNite Solar Classic 200 Charge Controller, 10,000 gallon rainwater collection system, etc.
  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    vtmaps wrote: »

    Which pump, exactly, are you looking at? You may be correct that you do not need a pressure tank... there are some pumps with variable speed motors that are designed to work without pressure tanks.

    --vtMaps

    I suppose it would help to mention that. To any moderators: I'm not sure if its ok to post links on this forum so if not, please delete the links. The pump I was originally looking at was a Flojet Model# 04300143A (link) but now that you mentioned variable speed pumps, I seen northern tool also has a couple of those, the smaller of the 2 being a Remco Model# 55AQUAJET-AES (link). In this case, it may be better to spend 10 bucks more on the variable speed pump and forget about the pressure tank and switch for now?
  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    Hi Levsmith,

    Yet again, we have some similarities!...We're completely off-grid (solar only) and we rely solely on rainwater for our water source. Compared to a well, we're lucky in that our rainwater storage tanks (two polyethylene storage tanks, each one holds 5,000 gallons for a total of 10,000 gallons of storage) are above-ground, so we only have to pressurize the water for household use; no need to pump it "up" from the ground, so to speak.

    For our household water system we have a 24 volt DC Aquatec Series 550 pressure booster pump (factory pre-set to 40psi cut-in/60psi cut-out, 4.5gpm) which is wired to a Square D pressure switch. The Square D pressure switch is manually set to 30 psi cut-in and 50psi cut-out. We also have a 33 gallon pressure tank, which, as several posts have indicated, prevents the pump from coming on and off. Like vtmaps pointed out, if it's a variable speed pump then those are designed to operate without a pressure tank most times. However, if you have a cut-in/cut-out style booster pump then a pressure tank is the way to go. It prevents the pump from cycling, thus saving wear and tear on the pump. We have a tankless hot water system that requires a minimum water pressure of 20psi to work, so we went with 30psi cut-in/50psi cut-out. The nice part is that the Square D pressure switch is easily adjustable via a set-screw, and can handle the DC current of a 24 volt DC pump (max amperage of our 24v DC pump is about 8 amps af full 60psi pressure).

    Hope this helps!

    Again! Thanks for your reply as well! Just trying to understand things better, your pump is 60psi cut-out and pressure switch is 50. That means the pressure switch hits 50 and shuts the pump off before the pump reaches its cut out limit correct? Likewise, once the pressure switch reaches its cut in limit, the pressure is below the pumps limit, which kicks the pump on, if I'm understanding things correctly, I hadn't thought about the tankless hot water heater requiring a minimum water pressure. I plan to go tankless as well so I'll have to check into that. Thanks again!
  • zonebluezoneblue Solar Expert Posts: 1,218 ✭✭✭✭
    Thats true vt, some of the newer rv pumps have automatic pressure controllers in them, but they tend to more expensive (and less reliable), and most people soldier on with the likes of shurflow 2088, now 4008, the flojet equivalents etc. They have a simple in built pressure switch, plus also sometimes a so called " bypass valve" which is supposed to help with the thrashing (but doesnt).

    Pumps, any pumps, are rated for X many starts per hour. Say 40. If you connect such a RV pump to a load such as a water filter, or a tap open a dribble, the pump will switch on and off many times a second, and thus the pumps life will be severely shortened. Believe me if you try it, youll end up with a pressure tank. Shurflo make a small tiny one, http://www.campingworld.com/shopping/item/shurflo-accumulator-tank/2290 which is good for RVs. If you have a little more space you can get steel ones in the 10-20 liter range for about the same price. Just remember that the bladders dont last for ever (2-5 years) (And thats exacerbated by forgetting to maintain the air pressure in them.) (which you do). (The more movement in the bladder the more stress on it).(To charge them, (bimonthly) you need to drain the pressure tank, pump to 2-3 pounds less than the cut in pressure of the pump). (which should result in the tank being roughly half air, half water). (So you need a pressure guage for the water... and for the air.) (Hopefully thats explains things).

    1.8kWp CSUN, 10kWh AGM, Midnite Classic 150, Outback VFX3024E,
    http://zoneblue.org/cms/page.php?view=off-grid-solar


  • Hill_CountryHill_Country Solar Expert Posts: 96 ✭✭
    Hi Levsmith,

    Yes, you are exactly right... the Square D pressure switch cuts in below the factory-set cut-in pressure of the Aquatec (30psi for the Square D vs. 40psi for the Aquatec)...which means that the Aquatec pump will run because the pressure is below 40psi. Similarly, the Square D pressure switch turns off when the pressure reaches 50psi, which means the Aquatec booster pump never makes it to 60psi. I didn't want to fiddle with the Aquatec adjustment because it is much more sensitive and more difficult to adjust. The Square D pressure switch is only about $20 at most hardware stores, so it's worth it for me. Another thing to keep in mind is with the size of the pressure tank vs. your pressure pump (not your well pump). We have a 33 gallon pressure tank which, when you have it pre-charged for 28psi (you want your pressure tank to be pre-charged about 2 psi below your cut-in pressure) and are using it in a 30psi cut-in/50psi cut-out setup will give you about 10.5 gallons of "drawdown". Drawdown refers to how much water you'll actually get out of the pressure tank before the pressure tank reaches the cut-in pressure (in this case, 30psi). That means that if our pressure tank is charged to 50psi, we can use 10.5 gallons of water before the pump will kick on again and recharge the pressure tank. With our 4.5gpm pump, it takes about 2 minutes or so to recharge...most days our pump will only run about 4 -5 times (showers, kitchen sink, laundry...but no toilet...we have a composting toilet). Just like solar, it's important to plan your water system so you get a setup that's right for you!
    100% Off-grid with: 8 Solarworld 275 Watt Panels, 8 Concorde SunXtender 405aH 6v AGM Batteries, MS-4448PAE 48v Inverter, MidNite Solar Classic 200 Charge Controller, 10,000 gallon rainwater collection system, etc.
  • BB.BB. Super Moderators, Administrators Posts: 30,658 admin
    No problem with links to products as long as it moves the discussion forwards.

    -Bill "moderator" B.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Dave AngeliniDave Angelini Solar Expert Posts: 5,241 ✭✭✭✭✭
    All these posts have really good info for someone planning to buy land. About 1/4 of my clients have done similar. The bulk of the rest just buy a good used RV or trailer and put a water tank in the back of a truck.
    If you really are going to build something (and many just dream) you will be busy and not have time for all this now. This will give you time to learn and maybe providence will take over and show you the "way".
    Good Luck!
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    BB. wrote: »
    No problem with links to products as long as it moves the discussion forwards.

    -Bill "moderator" B.

    Thanks Bill, I'll try to remember that for future posts.
  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    All these posts have really good info for someone planning to buy land. About 1/4 of my clients have done similar. The bulk of the rest just buy a good used RV or trailer and put a water tank in the back of a truck.
    If you really are going to build something (and many just dream) you will be busy and not have time for all this now. This will give you time to learn and maybe providence will take over and show you the "way".
    Good Luck!

    Thanks for the reply Dave. I am about 90% sure it's going to happen as long as the bank comes through on the land loan. I figure being young (27) and single, now is the best time to do it. If I wait until I have a girlfriend or wife, I would have to try and talk her into it. If I do it now, I think it will be easier to convince someone when they can actually see it working rather than them trusting me that it will work.

    I have thought about buying a cheap camper just to get started but I figure I can build a 2 car garage for not much more and be a lot better insulated. The problem in my situation is I don't think I could leave the tank exposed with the cold weather that we get so I have a spot in my garage plan layout to put the tank. I am looking at a vertical tank so it doesn't take up a lot of floor space, small enough footprint to fit in a closet.
  • BB.BB. Super Moderators, Administrators Posts: 30,658 admin
    I will put one warning out there... Personally, I like to pay off anything big (home, etc.) as fast as I can. And while homes in major metro areas can be pretty easy to sell (at the right price, and in good markets)--Land (with out or with a trailer/RV/mobile home) is usually another issue completely.

    In many areas, land is very difficult to get a bank loan on--And Mobile homes do not (usually) add much value to the land. Many times, the owner of the property has to carry a significant note (mortgage) to sell the property. If you ever need to get a loan on the property, sell the property, or eventually move for some reason--You can be left with a significant white elephant to unload.

    And while you might be willing to forgo major utilities (power, Internet, etc.)--Other buyers may not be so willing (keeps your property prices low, difficult to get a loan). Have you looked at the cost/possibilities of getting utility power to the property? And what is possible now, may not be in the future (utilities are not making it any cheaper to wire up remote properties).

    I have a friend that is looking for a piece of property in a relatively rural area... The properties are not selling quickly, and getting bank financing is difficult. Bare land seems to be pretty flat in price--Sellers with mobile homes seem to expect a pretty high price. And overall prices have still been pretty much at a recent historic low.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Dave AngeliniDave Angelini Solar Expert Posts: 5,241 ✭✭✭✭✭
    Pay as you go for sure! Never get into anything like this that you cannot afford to walk away from! If you do it right you will love it! 23 years now without a power bill is some serious change!
    I think the OP has a good plan but good to play the good cop bad cop Bill ! You should see the failed dreams I have in the Yachting world! Really hard to drown offgrid! :D
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    BB. wrote: »
    I will put one warning out there... Personally, I like to pay off anything big (home, etc.) as fast as I can. And while homes in major metro areas can be pretty easy to sell (at the right price, and in good markets)--Land (with out or with a trailer/RV/mobile home) is usually another issue completely.

    In many areas, land is very difficult to get a bank loan on--And Mobile homes do not (usually) add much value to the land. Many times, the owner of the property has to carry a significant note (mortgage) to sell the property. If you ever need to get a loan on the property, sell the property, or eventually move for some reason--You can be left with a significant white elephant to unload.

    And while you might be willing to forgo major utilities (power, Internet, etc.)--Other buyers may not be so willing (keeps your property prices low, difficult to get a loan). Have you looked at the cost/possibilities of getting utility power to the property? And what is possible now, may not be in the future (utilities are not making it any cheaper to wire up remote properties).

    I have a friend that is looking for a piece of property in a relatively rural area... The properties are not selling quickly, and getting bank financing is difficult. Bare land seems to be pretty flat in price--Sellers with mobile homes seem to expect a pretty high price. And overall prices have still been pretty much at a recent historic low.

    -Bill

    Thanks for the concern and warning Bill. Depending on the circumstances, it can be somewhat difficult to get a loan on land around here. The ag bank wants an income plan and traditional banks want you to build a house which means getting a mortgage since they expect a complete house in just a few months. I am lucky in that regard. My old college roommate is from a little oil town not too far away and when oil was high, nobody was taking out any loans so they were looking for people who needed loans and they gave me the OK. No strings attached on what I can build or when.

    I have thought about the issue of selling it if I have to. I have looked into getting utilities to the site. Power is 1/2 mile away and the power company wants 16k to get electricity to the place. If the situation arises that I need to sell it, I will probably pay the 16k to have it connected to the grid. Otherwise I would probably have to find someone who wants to live off grid and has the cash to buy it because I doubt too many banks would loan on a place that isn't hooked to the grid, unfortunately.

    Sounds like it is just the opposite here with the market. If a rural property with a house is listed at a decent price, it is usually under contract the same day. Even smaller bare lots sell pretty quick unless they are in a new subdivision right outside of town where they are asking 2-3x the price of rural land. A lot of homes in town sit for a little while. But it does sound the same with mobiles homes. For some reason people think when they put a $10k single wide on a $30k lot, they can ask $100k.
  • Dave AngeliniDave Angelini Solar Expert Posts: 5,241 ✭✭✭✭✭
    Since you will be on a budget early in this project I would hope you are close to your work and have a decent source of firewood for a wood stove. This of course will help immensely with finding a girlfriend as you put it. Just the same as keeping her dry on a boat cruise of the world. If you have water, firewood and sunshine it really makes offgrid alot more feasible cost-wise. The biggest challenge in places that need cooling because of humidity, or places that do not cool off at night is the power to run the cooling.

    Even that challenge is far easier today. When I went out on a multi ocean boat cruise there was GPS, desalination, and autopilots. The people before that really had a lot more on their plates. You sound like a very smart guy. Go read all the posts here again and hopefully you can easily get internet eventually out to where buy. Some rural phone companies will pull in a phone line but it may take years for them.
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • levsmithlevsmith Solar Expert Posts: 56 ✭✭
    Since you will be on a budget early in this project I would hope you are close to your work and have a decent source of firewood for a wood stove. This of course will help immensely with finding a girlfriend as you put it. Just the same as keeping her dry on a boat cruise of the world. If you have water, firewood and sunshine it really makes offgrid alot more feasible cost-wise. The biggest challenge in places that need cooling because of humidity, or places that do not cool off at night is the power to run the cooling.

    Even that challenge is far easier today. When I went out on a multi ocean boat cruise there was GPS, desalination, and autopilots. The people before that really had a lot more on their plates. You sound like a very smart guy. Go read all the posts here again and hopefully you can easily get internet eventually out to where buy. Some rural phone companies will pull in a phone line but it may take years for them.

    Thanks again Dave! I will be close, the property is only about 25 minutes away. As far as the firewood goes, unfortunately, this land has NO trees! Most of the ground around here is the same way because there is a lot of farming. I will be planting some trees for harvesting but until they are ready my parents have 150 acres with LOTS of trees and they live about an hour and a half away. I figure to begin with I will probably just get a small propane heater, surely a 600sf structure wouldn't cost too much to heat.

    Cooling will be an issue here but I am hoping the timing works in my favor. If all works out as planned, I will move into the new place in fall of next year and get my current house on the market. That should give it time to sell and I can use the money from it to upgrade my solar system before the next summer. I have been looking at mini splits for cooling.

    As far as the internet goes, that's the easy part! There are a few companies that do "line of sight" internet around here and that land just happens to be in the service area. Basically you have a small satellite dish pointed towards the nearest tower. Its a little more expensive than traditional internet but there are no limits on usage like some phone companies. My parents have the same type of internet and it works well for them.
  • davemacdavemac Registered Users Posts: 39 ✭✭
    Hi Levsmith,

    We have a 33 gallon pressure tank which, when you have it pre-charged for 28psi (you want your pressure tank to be pre-charged about 2 psi below your cut-in pressure) and are using it in a 30psi cut-in/50psi cut-out setup will give you about 10.5 gallons of "drawdown". Drawdown refers to how much water you'll actually get out of the pressure tank before the pressure tank reaches the cut-in pressure (in this case, 30psi). That means that if our pressure tank is charged to 50psi, we can use 10.5 gallons of water before the pump will kick on again and recharge the pressure tank. With our 4.5gpm pump, it takes about 2 minutes or so to recharge...most days our pump will only run about 4 -5 times (showers, kitchen sink, laundry...but no toilet...we have a composting toilet). Just like solar, it's important to plan your water system so you get a setup that's right for you!
    I just wanted to geek out here to calculate Hill Country's energy usage... anyone care to check the math?

    Water Usage / day = 10.5 gallons drawdown x 5 = 52.5 gallons / day
    Pump Energy Draw (from Aquatec 550 pump spec sheet) = 5 amps (24 V, 120 watts)
    Pump Flow Rate (from Aquatec 550 pump spec sheet) = 2.6 gallons/min
    Pump Run Time = 52.5 gal @ 2.6 gal / min = 20 mins run time (30 - 50 psi)
    Pump Power Usage = 120 watts for 20 mins = 120 x 1/3 hr = 40 Wh

    Water Pressure Power Requirement = 1 gallon @ ~45 psi requires ~  .76 Wh  (is this in the ballpark?)

    I wonder how that compares to a 24 V DC variable water pressure pump without the large pressure tank?
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