Water Pump Specifications

hemmjo
hemmjo Solar Expert Posts: 90 ✭✭
I am working with a mission in the Dominican Republic. I have been told that we have a water pump that needs to be installed in a new hand dug well. All I have seen are some photos. As near as I can tell from trying to interpolating the photos, I think the well is about 15-20 feet deep. I am not sure the water level I am going to guess there is not much more than 2-3 feet of water in the well. I have NO IDEA what the capacity of the well might be. The water will be used ONLY for showers and perhaps cloths washing

Can tell you that we have a 500 gallon tank on top of one of our buildings. It is about 400 feet away and maybe 40 vertical from the well. We DO NOT need to pump 500 gallons each day. 50-100 gallons would be a heavy use day. Usually we get 7-10 days from a full tank. Even if we pump only .5 gpm we can easily keep the tank full only running a pump 2-3 hours per day after the initial fill.

Yes I know, this is not enough information to do much. But here is what I am faced with and why I am asking. I was emailed the specifications for the pump. Myers Peripheral Vane Pump, Part # 201T0500, Model: BP5, 1/2HP 127v, 60Hz, 3450 r/min, 0.37 kW,
Qmax 45 L/min Hmax 40 m, Q 5 - 35 I/min @ H 35 - 5 m.

I have deciphered these specs to mean;120v, 4 amps, 12 gpm max, 130 ft of head or 60 psi max, 1.3 gpm @ 115ft, 9.2 gpm @ 16 ft

I have no idea the suction lift or dry run capability in case the pump looses prime. I cannot find any information about this specific pump. Does anyone have experience with this. The Myers site does not show anything about vane pumps.

I was thinking we would use a small 12volt diaphram pump which would be lowered into the well so the suction lift is not much and let it run for an longer time, at low flow to keep the well from being turbulent inside. But someone gave us the above pump, should I try to use it or get a different one?

I am leaving in 3 weeks to install this pump, which we will run from generator until we get our solar system designed.

What do you off grid users do for water?

Any thoughts would be appreciated.

Thanks,

John
Two systems in the Dominican Republic  http://villagemountainmission.org/
installed Feb 2014 at 19.796189° -70.893594°, Classic 150 + WBJR, KISAE SW1210, MN Battery Monitor, IOTA DLS 55/IQ4,  4- Solar World 275w, 4-6v x 225ah Trace Batteries
installed Feb 2015 at 19.795733° -70.893372°, same components  as above
Honda PowerMate PC0497000, 7000/8750w generator - powers the well and chargers maybe once a week






Comments

  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Water Pump Specifications

    I can think of a 100 ways to do it. I don't know the diameter of the well, but if it's hand dug, lets say it's 2.5 feet in Diameter. Take a box / wal- mart tub and put a bulk head fitting in it for intake and let it float in the surface of the water with a 12 v diaphragm pump inside. It would float up and down with the water level or lower the pump on a rope and let the intake float.

    12 Volt submersible pumps aren't cheap, but one would work ok. You have to figure out the control and maybe some kind of a run dry switch if the well runs dry.

    As long as you keep the suction down to about 5 feet or so , it be fine.

    The Myers pump would work if you have the power to run it and keep it primed, It can't run dry. The vanes tend to wear out if there is any sand.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,599 admin
    Re: Water Pump Specifications

    Another device to look at is a VFD (variable frequency drive). For use with 3 phase motors and motors with external start capacitors. It can "soft start" the pump and even vary the RPM to keep the pump operating at a speed that does not over pump the well (i.e., slow pumping).
    BB. wrote: »
    Some discussions about VFD (Variable Frequency Drives)... Basically a variable frequency inverter with (typically) three phase output. Used to soft start motors (handy for 3 phase well pumps, or pumps with well head starting capacitor) and can also turn an AC motor into a variable speed motor (very handy for pumping applications).

    WELL PUMP and Inverter QUESTION

    Wind/solar for large scale pumping etc (out of my depth!)
    could use knowledge - using Gould jet pump - transfering from 230vAC to ? DC (new link/thread 10/27/2012)
    Help required to design off grid system (information on possibilities to connect "standard VFDs direct to solar panels) (new link 1/13/2013)

    It would be best to find out what is available locally--so you can get parts/support without having to wait for a flight or mail from off island.

    I would be tempted to look at a pump like this. Direct power from solar array, relatively low volume and high pressure output available. Price is not fun though. You would have to install it 1/2 way down the well (and make sure it did not get flooded out during storms).

    http://lib.store.yahoo.net/lib/wind-sun/solaram-specs.pdf

    At that price, a $2,xxx Grundfos submersible flex power pump looks "cheap".

    The direct connect to solar panel pumps are pretty nice. No batteries, inverters, etc. to maintain/replace every X years. Nobody can kill the battery bank by letting the pump run on low battery bank, etc... The Grundfos SQF pumps can take a wide range of solar panel, battery, or even generator AC power.

    You might give NAWS (our host) a call. They would have more information than I about what is best for pumping from a hand dug well.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Water Pump Specifications

    I used a conventional well pump (1/2 hp, 240VAC motor) because I have a 400' run from the inverter to the pump. I then pump up hill to elevated storage tanks, that feed fire sprinklers, plant water, and domestic drinking water. The elevated storage means I have water at all times pipes are not broken. A standard, generic well pump can be replaced easily. The pump is on a timer to allow it to run, (if the float switch says the tanks are low) for several hours in the middle of the day, after the batteries have some charge, and clouds are unlikely.

    Mike
    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 ,

  • hemmjo
    hemmjo Solar Expert Posts: 90 ✭✭
    Re: Water Pump Specifications

    Thanks for the input thus far. I think a plan is coming together. The vane pump we have is not the thing to use so it is out of the equation.

    So far the best solution seems to be a small ShurFLo 12 volt pump model 8000-443-136. This will pump 73.8 GPH at 60 psi drawing about 7amps. In reality we will need less than 40 psi to move the water through 450' of pipe and up the 40-50' rise of the hill to the tank.

    Check my math to see if this makes sense. 12 volt pump at 7 amps = 84 watts.

    If it takes 7 hours to fill our 500 gallon tank that is 7h x 84w = 588 watt hours to fill the tank.

    If we typically use 100 gallons or water per day, we will use about 100g/73gph= 1.4 hours x 84w = 120 watt hours per day.

    If I get one SolarTech SPM020P 20 watt panel and a SunGuard 4.5 amp controller it seems we need about 6 hours of good sun to recharge the batteries for each hour we run the pump. We typically have between 10-13 hours of sun at our location. So this seems within reason.

    My next question is in regard to batteries. This is going to be the most expensive part. I will have to get them in country, shipping is out of the question. A typical deep cycle battery is around 220 amp hours at 6 volts. So if I get two of these that is 220 amp hours at 12 volts, or 2640 watt hours. That seems plenty big enough, is it too much battery?

    I know it is not the best solution, but, how long do you think a regular automotive battery would last in this situation?

    Finally the SunGuard specs say it is set for gelled or sealed batteries and is not adjustable. Will this be bad for wet batteries?

    Thank You,
    John
    Two systems in the Dominican Republic  http://villagemountainmission.org/
    installed Feb 2014 at 19.796189° -70.893594°, Classic 150 + WBJR, KISAE SW1210, MN Battery Monitor, IOTA DLS 55/IQ4,  4- Solar World 275w, 4-6v x 225ah Trace Batteries
    installed Feb 2015 at 19.795733° -70.893372°, same components  as above
    Honda PowerMate PC0497000, 7000/8750w generator - powers the well and chargers maybe once a week






  • BB.
    BB. Super Moderators, Administrators Posts: 33,599 admin
    Re: Water Pump Specifications

    First, the hours of sun is not correct. We talk about hours of "noon time equivalent sun" per day... For Santo Domingo, Dominican Republic with the panels set to 28 degrees from horizontal (using this site Solar Electricity Handbook--I don't know where the data came from) for a fixed array:

    Santo Domingo
    Average Solar Insolation figures


    Measured in kWh/m2/day onto a solar panel set at a 72° angle:
    (For best year-round performance)

    Jan
    Feb
    Mar
    Apr
    May
    Jun


    4.88
    5.28
    5.65
    5.61
    5.47
    5.68


    Jul
    Aug
    Sep
    Oct
    Nov
    Dec


    5.59
    5.14
    5.11
    5.15
    4.88
    4.74




    That gives you a minimum of 4.74 Hours of Sun per day...

    Assuming you need 120 WH per day, and we use a 0.66 (66%) safety factor (never plan on getting 100% of your predicted energy every day:
    • 120 WH * 1/0.66 = 182 WH per day with fudge factor

    Assuming 0.61 DC system derating, 4.74 hours of sun minimum (20 year long term average):
    • 182 WH per day * 1/0.61 system derating * 1/4.74 hours of sun per day = 65 Watt array minimum

    Two ways of calculating battery size. First is daily load with 1-3 days of stored power (no sun) and 50% maximum discharge:
    • 182 WH * 1/12 volt battery * 2 days of no sun * 1/0.50 maximum discharge = 61 AH @ 12 volt battery (deep cycle battery)

    The second is rate of charge based on 5% to 13% rate of charge:
    • 65 watt panel * 1/14.5 volts charging * 0.77 panel+controller derating * 1/0.05 Rate of charge = 69 AH @ 12 volt maximum recommended
    • 65 watt panel * 1/14.5 volts charging * 0.77 panel+controller derating * 1/0.10 Rate of charge = 35 AH @ 12 volt nominal
    • 65 watt panel * 1/14.5 volts charging * 0.77 panel+controller derating * 1/0.13 Rate of charge = 27 AH @ 12 volt minimum

    So, something like a 60 AH @ 12 volts would meet the minimum requirements. Personally, I would recommend a larger array (2x larger or around 130 Watt array) to allow for the fact that you will not be there everyday to monitor the system. A larger array would help the battery last longer (stormy weather, more water/power usage than planned, etc.). A ~130 watt panel is usually shippable via standard methods. If you go >>130 watts, you usually need special shipping methods (more expensive). Or, a pair of ~65 watt panels in parallel, etc...

    If you must use a 12 volt automotive battery--These are not designed for deep cycling. You probably only want to discharge that to around 85% state of charge. if you use a larger array and figure on only one day of pumping--preferably mostly done during daylight--Such a battery may be OK. If you cycle the battery deeper, it will not last near as long.

    Anyway, that is the basic math. Obviously, you need to redo the numbers for the actual hardware (solar array, battery used, etc.).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • hemmjo
    hemmjo Solar Expert Posts: 90 ✭✭
    Re: Water Pump Specifications

    Ok thanks for data analysis. Thank you for your input. As you know as I get deeper into this I get more questions.

    I got my sun information here.. http://www.suncalc.net/#/19.7983,-70.8895,17/2012.12.11/12:31 The latitude and longitude are at our site in the Puerto Plata/Luperon region on the North Coast. I was thinking the yellow band was usable sun light.

    So I am way low with my calculations. You are suggesting I ideally need about 130 watts of panel capacity. Since we are in such a remote location, we transport as much as we can in checked baggage. It is way more reliable and cheap when you can spread the load out among 10-12 people. So physical size becomes an issue

    With your calculations and our transportation needs in mind, my revised plan is to start with one SPM040P 40watt panel. We will see how that works, then add additional panels if necessary. We have our generator if it is not enough to start. Additional groups come down a couple of times a month in the summer.

    If I end up needing 3 x 40w as your numbers suggest, the Morningstar SunSaver Solar Charge Controller 6 Amp, as suggested on the 40 watt panel page can only handle 2 x 40 watt panels. What is the next step up from that?

    Then again back to batteries. I am going to be limited to what is available in country. I actually seen and priced, 6 volt NAPA deep cycle batteries there a year or so ago. As I recall they were in the range of 200AH and around $120-$150 each. These would supply plenty of battery capacity. With costs in mind, how would I even get something close to the 69AH the calculations suggest?

    Is there some control to limit the level of battery discharge. It would shut off the pump if the batteries get too low? This is probably a low priority as the pump will not operate automatically, someone will flip a switch on when the tank needs to be topped off and flip it off when water runs out the over flow. We could just mount a volt meter to keep track of things.

    We do not really need the system to run "unattended" for extended periods. We don't need water when we are not there and security is a concern for things. We will need to store the panels away if we are gone for extended periods. We will be building a small concrete block pump house over the well to protect the well, house the batteries and controller and provide a suitable mounting place for the panels. I anticipate the small roof will "hinge" open and closed to expose and secure the panels and adjust angle for the season.


    Thank you again for sharing your knowledge,

    John
    Two systems in the Dominican Republic  http://villagemountainmission.org/
    installed Feb 2014 at 19.796189° -70.893594°, Classic 150 + WBJR, KISAE SW1210, MN Battery Monitor, IOTA DLS 55/IQ4,  4- Solar World 275w, 4-6v x 225ah Trace Batteries
    installed Feb 2015 at 19.795733° -70.893372°, same components  as above
    Honda PowerMate PC0497000, 7000/8750w generator - powers the well and chargers maybe once a week






  • BB.
    BB. Super Moderators, Administrators Posts: 33,599 admin
    Re: Water Pump Specifications

    Hi John,

    You might want to try and PM (Private Message) KeithWHare. He has done a lot of similar work in Haiti. Here is one thread he has posted about his project:

    Well & Pump at a clinic in Haiti


    If you cannot get a reply from him, send me a PM I will try and send an email directly.

    The numbers I suggested were a minimum value. You can go larger--But the issue with going with a larger battery bank is that you should have more solar panels too (to maintain that ratio of 5%/10%/13% of charging current).

    The 6 volt 220 AH deep cycle batteries are usually a pretty good deal. "Cheaper" because they are readily available, usually "true deep cycle" rather than automotive or "marine" type batteries, they will give you a good service life.

    The issue with something Like SunCalc (I think--I have not seen it before) is that is good enough for determining if shading (buildings, trees, mountains) would be an issue for the site. But it does not include local weather conditions (marine layer, winter/hurricane season, thunderstorms, etc.). Also there is the "geometry" of your solar array--Tracking vs fixed vs angle up/down/south/non-south orientation.

    Anyway, I try to be conservative. A slightly over designed power system that meets your needs plus a little extra is usually better than one that only meets 7%% of your needs--Or works the first year, then has "issues" for the next 5 years.

    Regarding panels--You have to choose what meets your needs. Getting good quality is important. But panel price ($$$/Watt) may not be as important as the ability to ship/carry to site (i.e., a 220 watt panel is "cheap" at $2/watt, but you would never get it there in one piece/or spend a large amount of cash trying to get it there vs spending $10 per watt for a 40 watt panel).

    Note that you can parallel charge controllers to a single battery bank. They will function OK. For example, you could create a modular power system by paring a 40 watt panel with a 4.5 amp controller.

    wind-sun_2245_46837715

    No lights, no meters. Just one per 40-80 watt panel.

    Wire up 1, 2, or 3 solar panels for your starter bank... Wire in more (directly to the battery bus) as you determine your power needs/battery bank increases. Eventually, you probably will design/build a larger system (lights, clinic, school, cell/computer power, etc.)--And then you can re-deploy the 40 watt "modules" the next project.

    A pair of 220 AH @ 6 volt batteries connected in series for a 12 volt @ 220 AH battery bank would use a solar array in the range of:
    • 220 AH * 14.5 volts * 1/0.77 panel+controller derating * 0.05 rate of charge = 207 Watt array minimum
    • 220 AH * 14.5 volts * 1/0.77 panel+controller derating * 0.10 rate of charge = 414 Watt array nominal
    • 220 AH * 14.5 volts * 1/0.77 panel+controller derating * 0.13 rate of charge = 539 Watt array "cost effective maximum"

    I would not even suggest that you get the 220 AH batteries until you can get around 200 Watts of charging on the battery bank (unless you plan on AC Charging with the generator). Below 5% rate of charge, the batteries will not last very long and any loads you place on the system will tend to slowly discharge the battery (over the long term). (yes there are people that have run very small loads with a 3% rate of charge--But I would suggest avoiding it).

    Obviously a 220 AH @ 12 volt battery bank with a 207-539 watt array is much more capable--Lights, charging batteries for cell phones/computers, more water pumping, etc. Only you can make those trade offs (cost, maintenance, shipping components, training local users, etc.).

    And please note, my above calculations are not "that accurate"... I just carried out the extra digits so you can follow my math and catch any errors I may have made in calculations.

    Solar power systems are difficult to "expand" over time. You can usually double the battery bank/loads by adding hardware... But more than that, you are usually better off starting from scratch with a new design (larger batteries, heavier wiring, larger output power, you need a new inverter, much larger power, you really should go to a 24 or 48 volt battery bank, etc.).

    Automating a solar power system is always an issue of cost and function. Measuring battery voltage does not accurately reflect state of charge (resting voltage, charging voltage, voltage under various loads, temperature compensation--hot batteries run at a lower voltage, etc.)... If this is being done manual--Iw I would just wire in an LCD volt meter such as one of these ($32 or less):

    wind-sun_2244_11508079
    Tell folks that if they see > 13.5 volts when the sun is up, they can run the pump. If they see <12.3 volts under load, then don't run the pump too much. If they see <11.5 volts--Stop using the pump (day or night). If they see >14.2 volts for several hours per day when the sun is up--Then everything is well (check battery water once per month, only fill (not all the way) with distilled or filtered (very clean) rain water.

    Yes, you could put a voltage sensitive switch on the battery bank--But you get into what voltage to set it at. And somebody is going to bypass it the first time they need water and the system "shuts down".

    Also, I would get a few "inexpensive" DMM to keep down there. I also very much like the Sears DC Current Clamp Meter (really DMM) for ~$60. Makes it much easier to diagnose/maintain DC power systems. Cheap enough that it can be damaged/walk away without killing your funds.

    You could, and probably will, eventually go more complex with your system and monitoring... But for a small starter system--It is usually not worth the costs/training to do it.

    For example, you could monitor power usage with a DC AmpHour/WattHour meter so you can size the system based on power used/collected. The next step up would be some sort of Battery Monitor--But, again these start pushing the costs on a small system.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Water Pump Specifications

    I was thinking about what BB said re costs.... a cost benefit might be in order from your perspective, that looks at the cost of a new (disposable) battery each year, ie one that is available locally VS getting exactly what you need and shipping it in when you head south, noting that the expensive one will need to be hooked up to a CC to keep it healthy while you are away.

    hth
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • hemmjo
    hemmjo Solar Expert Posts: 90 ✭✭
    Re: Water Pump Specifications

    Ok thanks for all of the input from those who have experience with this.

    Here is that I have settled on so far.

    2 - 30 watt SolarTech panels are close to the minimum suggested by BB early on in this thread. 30 w was selected mainly of the physical size because of transportation restrictions, they are close to the specs. and multiples will work to increase capacity as needs are verified

    1 - Morningstar : SS-10L-12V SunSaver 12 Volt charge controller. This was selected because of the LowVoltageDisconnect feature, the ability to select gelled or flooded batteries, and the ability to add 2 more 30 watt panels if necessary to bump the array up to close to the 130 watts again suggested by BB earlier in the thread.

    I will have to get batteries in country after I get there. It may end up being just a automotive battery if the deep cycle batteries are too large for the charge capability of the panels at this point. If the charge controller has LVD, will that help extend the life of the automotive battery if that is all I can get? I may just purchase a new battery for our truck and and use the old one for now, while searching for the correct deep cycle solution.

    The MorningStar installation manual shows fuses in the charging line as well as the load line as I would expect. However there are no fuses in the line between the controller and the panels. Should there be?

    I was thinking of getting a Midnite Solar Baby Box, and use breakers as overload protection and to switch off the pump. Is this a bad idea or just use inline fuses and a switch for the pump?

    I need to order these items ASAP, in order to be sure to have them when I leave next week.

    Thanks again for your help,

    John
    Two systems in the Dominican Republic  http://villagemountainmission.org/
    installed Feb 2014 at 19.796189° -70.893594°, Classic 150 + WBJR, KISAE SW1210, MN Battery Monitor, IOTA DLS 55/IQ4,  4- Solar World 275w, 4-6v x 225ah Trace Batteries
    installed Feb 2015 at 19.795733° -70.893372°, same components  as above
    Honda PowerMate PC0497000, 7000/8750w generator - powers the well and chargers maybe once a week






  • BB.
    BB. Super Moderators, Administrators Posts: 33,599 admin
    Re: Water Pump Specifications

    You do not need a main fuse/breaker from array to the charge controller as long as the array voltage/current ratings do not exceed the controller's input ratings (fuses/breakers would not "fix" the problem anyway). Fuses/breakers are to (mostly) protect the wiring and if the wiring is heavy enough for the solar array, then over current protection is not needed.

    If you have three or more solar panels in parallel, then you usually need a series protect each panel from excessive current if shorted (check the spec sheet for required fuse rating).

    Some sort of fuse/breaker from the battery bank to each load circuit is a good idea.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset