Backup solar for gas station

I live in a small town, and the owner of the local gas station is asking me about what it would take to keep his led lights on, his cash register, and gas pumps running when the power goes out.

My original idea is to use a magnum PAE 4400 inverter with 4 200ah AGM batteries, with 6 250 watt panels.

However when I started looking at his electrical panel, he has a sub panel that runs his pumps, and it connected to a 100a breaker.  He only has 4 pumps, but they don't all run at once.  But how much power do these pumps take?

Obviously the magnum inverter won't work, because it only has a 30a ATS.  So I would need to get a 100A ATS.  But will the magnum 4400 watt inverter run a pump, and how long do you think 9600 watt hours will keep things running?

I didn't think those pumps would really take much power, especially since they don't run much, but maybe I am wrong, I was suprised by the 100a breaker, and I think each pump had a 30a breaker.



  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    First you need data on the pumps....  the pump motors are probably the greatest load and what is the likely hood of them all being started simultaneously?
    KID #51B  4s 140W to 24V 900Ah C&D AGM
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,442 admin
    Service stations may have some pretty stringent electrical safety requirements (explosion proof boxes/devices) and certification of pumps (local weights and measures).

    Anything is possible--And setting up for only one or two pumps to run on backup system can help....

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • davidwillis
    davidwillis Solar Expert Posts: 104 ✭✭
    Thanks.  I will see If I can find some data on the pumps.  I have contacted sinclare, hopefully the will get back to me.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    edited June 2017 #5
    Why solar and not a manual start generator (diesel or propane) on a pad with manual transfer switch ?  Is he expecting week long outages ?
    Or just a grid charger .
    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

    gen: ,

  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    mike95490 said:
    Why solar and not a manual start generator (diesel or propane) on a pad with manual transfer switch ?
    Or a gasoline generator?  They are cheaper and he has a lot of it, and he won't have the problem of "the gas degrades with time" since he can just pull from his own tank.
  • davidwillis
    davidwillis Solar Expert Posts: 104 ✭✭
    That is probably what he will end up doing.  I originally thought it would only take a little power to run his 200 watts of lights, his register, and a pump once in a while (seems like overkill to have a generator running full time for just that).  But if those pumps need 100 amps, then it will be better to just run a generator.
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    It's hard to believe the pumps would take anything like 30a. A lift of 10-15ft and flow of say 10gal/minute shouldn't take much of a pump.

    Even so, if outages are fairly rare, a generator is likely to be cheaper than a solar/battery backup system.
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter