Page 1 of 5 12345 LastLast
Results 1 to 10 of 43

Thread: 220 Well pump...how many panels, batts?

  1. #1

    Default 220 Well pump...how many panels, batts?

    Hi,
    I want to use solar for my 220 well pump. It is a 1.5 horsepower. The well is 160 ft. deep but the static water level is 76 ft. Pump is probably at 125 ft.

    I would like to use a Xantrex or similar 6000 watt inverter made for 220v.

    The pump needs to run at least 3-4 hours continuously per day. This is for irrigation. I only need it during the summer.

    How much solar and how many batteries would I need to do this?

    We are near Redding, California which has 12 hours of sun a day.

    2nd question is can I use the solar and switch to electricity at will?

    Please let me know if I am on the right track here.

    Thanks very much,
    Ellie

  2. #2

    Default Re: 220 Well pump...how many panels, batts?

    This is really not a good idea. The cost for enough solar power to achieve this (approximately 6 kW hours per day, not including surge requirements) is astronomical. You would be better off staying with utility power and adding a grid-tie system to off-set costs (if there's enough incentives in your area).

    Water is very difficult to pump. It's heavy. Even lifting 76 feet requires a lot of power. If there's no utility available (as in you want to get away from a remote generator set-up) you should look in to alternative pumps http://store.solar-electric.com/sodcwapu.html rather than try to build a battery-based solar electric system to supply the existing pump.

    Sorry this is not a 'happy' answer.
    1220 Watts of PV, OB MX60, 232 Amp hrs, OB 3524, Honda eu2000.

    Ohm's Law: Amps = Volts / Ohms
    Power Formula: Watts = Volts * Amps

  3. #3
    Join Date
    Sep 2006
    Location
    Willits, CA
    Posts
    5,648

    Default Re: 220 Well pump...how many panels, batts?

    If you already have 220VAC at the well pump, you are doing good, anything else you do will cost you lots of $$ . I know, I just installed 1/2 hp pump, 220V off an XW6048. http://tinyurl.com/LMR-trenches

    is your utility power unreliable?

    My suggestion for solar is:

    1.5hp is a HUGE pump. can you go smaller, and pump for longer time, the starting surge is going to be the limiting factor. (batteries and inverter) 1,400W running load

    if you can't go smaller pump, consider a 3phase motor then, and use a single-3 phase motor controller to allow a "soft start" and install power factor correction caps to get running PF to 1.0

    If you are sure you will only pump with good daylight, you can make a minimal battery bank to keep the pump running if a cloud comes by for a couple of minutes, you would need a 1,500W of PV.
    Then you trade off between smaller PV and larger battery bank, with many sizes along the way.
    http://tinyurl.com/LMR-Solar
    http://tinyurl.com/LMR-BigLug
    http://tinyurl.com/LMR-NiFe

    Grundfos 10 SO5-9 with 3 wire Franklin motor (1/2hp 240V 1ph # 214505 ) on a timer for 3 hr noontime run - Runs off PV
    Powerfab poletop PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe battery | 15, Evergreen 205w "12V" PV | Midnight ePanel || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT

  4. #4
    Join Date
    Mar 2006
    Location
    SF Bay Area (California)
    Posts
    21,002

    Default Re: 220 Well pump...how many panels, batts?

    Using the PVWatts website:

    Assume Sacramento CA, fixed array mounted at latitude-15 degrees (for summer power), system derating:

    • 0.77 (solar panels+charge controller) * 0.85 inverter * 0.90 (best batt eff) = 0.59 eff (assuming most pumping during full sun for better efficiency)

    "Station Identification"
    "City:","Sacramento"
    "State:","California"
    "Lat (deg N):", 38.52
    "Long (deg W):", 121.50
    "Elev (m): ", 8
    "PV System Specifications"
    "DC Rating:"," 1.0 kW"
    "DC to AC Derate Factor:"," 0.590"
    "AC Rating:"," 0.6 kW"
    "Array Type: Fixed Tilt"
    "Array Tilt:"," 23.5"
    "Array Azimuth:","180.0"

    "Energy Specifications"
    "Cost of Electricity:","12.5 cents/kWh"

    "Results"
    "Month", "Solar Radiation (kWh/m^2/day)", "AC Energy (kWh)", "Energy Value ($)"
    1, 2.50, 43, 5.38
    2, 3.91, 61, 7.62
    3, 5.09, 88, 11.00
    4, 6.44, 106, 13.25
    5, 7.28, 120, 15.00
    6, 7.58, 119, 14.88
    7, 7.81, 124, 15.50
    8, 7.55, 120, 15.00
    9, 6.79, 106, 13.25
    10, 5.24, 86, 10.75
    11, 3.29, 53, 6.62
    12, 2.42, 40, 5.00
    "Year", 5.50, 1064, 133.00
    Assume 106 kWHr per month minimum available power per 1,000 watts of solar panels.
    • 1.5 HP * 746 watts/HP * 1/0.50 motor eff = 2,238 Watt load
    • 2,238 watts * 4 hours per day = 9,072 WH = 9 kWH per day
    • 106 kWH per month * 1/30 days per month = 3.53 kWH per day per 1,000 watts of panels
    • 9kWH per day motor / 3.53 kWH per day per 1,000 watts of panels = 2,547 watts of solar panels minimum

    For an XW power system, you need a minimum of 100 AH per 1,000 watts of solar panels--So:

    • 2,547 watts of panels * 100 AH / 1,000 watts of panels = 255 AH @ 48 volts
    • To support starting loads and such--probably 500-600 AH minimum recommended (other may have better numbers than I.

    Now--Off Grid solar is not cheap (around $1-$2+ per kWhr if you include battery replacement and other maintenance). If you could use Grid Tied Solar- (utility power is available)-you would need fewer solar panels and a much less expensive system to operate.

    A Xantrex XW is a full Hybrid Inverter system with inputs for Utility Power and a second input for Generator AC power (basically a big UPS, uninterruptible power supply).

    You can also look at the in ground pump too... There are several pump manufacturers that can be connected directly to solar panels.

    SunPumps Solar Powered Water Pumps (in well and surface)
    Grundfos Solar Submersible Well Pumps (pump will run on solar or battery DC or 120 VAC direct)
    Dankoff SunCentric Solar Pumps (surface pump)

    These may not be good for sprayers that require constant pressure (pump output changes with available solar power levels) but would be a good way to bring water to a surface cistern/impoundment area.

    And use a smaller pump (ac or dc) to pressurize a sprayer system (if needed).

    In general, moving water and other mechanical jobs are vary costly to power with solar RE. If you can conserve (use pumps that are efficient and can be operated from solar panels directly) and use utility power where it makes sense (through Grid Tied)--it is usually a much better solution than using off-grid solar (plus battery bank) for these type systems.

    Your system sounds fairly large. You can do a few paper designs, but also talk with the experts and see what they recommend/design for your needs.

    A battery backed Solar RE system would really only make sense if you have no access to utility power (too far from grid, or no grid tied / net metering allowed). Battery maintenance and monitoring is a big expensive nightmare for a remote site.

    If you can split your pumping between solar direct (well to cistern--no battery bank) and a smaller pressure pump for sprinklers--you might come up with a cost effective solution.

    -Bill
    20x BP 4175B panels (replacement) + Xantrex GT 3.3 inverter for 3kW Grid Tied system + Honda eu2000i Inverter/Generator for emergency backup.

  5. #5

    Default Re: 220 Well pump...how many panels, batts?

    I sure appreciate the replies even if they are not "happy" ones. The reason I want to do this is that my electric bill in June, July and August is over $400.00 compared to under $100.00 for the other months. In California PGE is on a tier system and they really kill ya in the summer months.

    I have done the math and it is the well that is causing the huge increase. I am paying .30 per KWH in the 100%-200% tier.


    When I retire and am on a fixed income there is no way I could afford to do this, so I am looking into ways to manage it.

    I do have 9,000 gallons of rain barrels and they work well, but only lasted 34 days, darn it.

    I may have to give up on this idea and get a few more rain tanks.

    E
    Last edited by EllieThomas; June 29th, 2010 at 14:14 PDT. Reason: clarification

  6. #6

    Default Re: 220 Well pump...how many panels, batts?

    Shoot, it may be cheaper to just run my Gas Honda Generator for the few hours a day!!

  7. #7
    Join Date
    Sep 2006
    Location
    Willits, CA
    Posts
    5,648

    Default Re: 220 Well pump...how many panels, batts?

    Quote Originally Posted by EllieThomas View Post
    I may have to give up on this idea and get a few more rain tanks.
    E
    Get a couple of 3,000 tanks. Use a small well pump, and fill all night, at cheap rates.
    come watering time, now that the water is at ground level, you need much less pump to run the sprinkler system.

    And maybe water at night, when rates are low.

    I installed about 3,000 feet of drip irrigation, that uses about 1,200 gallons a day, for nearly an acre of tree orchard. I pump to 3, 3,000 gl tanks, and ran about 2,000' of 2" pipe to keep friction loss down. All solar, off grid. $$
    http://tinyurl.com/LMR-Solar
    http://tinyurl.com/LMR-BigLug
    http://tinyurl.com/LMR-NiFe

    Grundfos 10 SO5-9 with 3 wire Franklin motor (1/2hp 240V 1ph # 214505 ) on a timer for 3 hr noontime run - Runs off PV
    Powerfab poletop PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe battery | 15, Evergreen 205w "12V" PV | Midnight ePanel || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT

  8. #8
    Join Date
    Mar 2006
    Location
    SF Bay Area (California)
    Posts
    21,002

    Default Re: 220 Well pump...how many panels, batts?

    Conservation is key--looking at reducing usage and (looking at time of use billing) pumping water at night may help.

    However, be sure you understand PG&E's Time of Use / Tier system... The more you use off-peak pushes your off-peak into a higher tier and increased costs.

    You should look at a Grid Tied system. As far as I know, PG&E will connect a home GT system (unless there are special issues for your connection) and their one year net metering with (currently low) monthly connection fee--Solar GT can actually save you money.

    At this point, I would guess running a fuel powered pump could still cost you more than $1.00 per kWHour just in fuel costs.

    -Bill
    20x BP 4175B panels (replacement) + Xantrex GT 3.3 inverter for 3kW Grid Tied system + Honda eu2000i Inverter/Generator for emergency backup.

  9. #9

    Default Re: 220 Well pump...how many panels, batts?

    Quote Originally Posted by EllieThomas View Post
    I may have to give up on this idea and get a few more rain tanks.
    You know, this way of pumping water is also solar powered. Let evaporation do all of heavy lifting.

  10. #10

    Default Re: 220 Well pump...how many panels, batts?

    You guys are great!

    The tier system is that they take a year and average out what you use by month. As soon as you go over that average.... bingo, you are in another tier. You really can't win with this system. I use very little in the winter and then a lot in the summer.

    I have a 60 watt solar panel and 2 deep cycle 12 volt batteries. I use a shurflo 12v pump to pump the water from my tanks to the gardens. It really works very well. I simply don't have enough.

    You have helped me figure out that the rain tanks are the cheapest way to go after the inital cost of course.

    This is what I have been trying to figure out and needed some guidance and expertise in the solar aspect that y'all have graciously provided.

    Ellie

Similar Threads

  1. Using Panels directly to 12V Shurflo pump
    By lazza in forum Solar Water Pumping
    Replies: 12
    Last Post: May 29th, 2013, 9:16 PDT
  2. 12V heater from solar water pump panels
    By mjp24coho in forum Solar Water Pumping
    Replies: 17
    Last Post: October 10th, 2010, 21:33 PDT
  3. new batts absorb too high
    By lamplight in forum Off Grid Solar & Battery Systems
    Replies: 13
    Last Post: May 22nd, 2010, 14:47 PDT
  4. Multiple Smaller Batts VS Fewer Larger batts?
    By stereoman405 in forum Solar Beginners Corner
    Replies: 7
    Last Post: April 9th, 2010, 9:31 PDT
  5. L16 RE TWO Volt Batts
    By Robert Lake in forum Solar Product Reviews & Opinions
    Replies: 5
    Last Post: August 10th, 2009, 11:49 PDT

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •