Is there a way to measure total watts charged for the day?

SulfatedPlates
SulfatedPlates Registered Users Posts: 5
I have my killawatt, and have just realized how far away from reality our plans were.

We have reduced our power needs to 1800 watts a day average. And we have a "1000" watt system that I have seen lay 800 watts into the batteries. (27a @ 29v)

But now i need a way to determine how many watts I received from the sun each day, to match with the killawatt (watts out.)

Suggestions?

Comments

  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Is there a way to measure total watts charged for the day?

    What equipment is in your system? Please give us the specs for your PV panels, CC, battery monitor charger, inverter, batteries, etc?
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
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    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • BB.
    BB. Super Moderators, Administrators Posts: 33,422 admin
    Re: Is there a way to measure total watts charged for the day?

    There are various ways to monitor charging current:
    • Many charge controllers will log amount of AH collected per day
    • Doc Watson (only reads current "one way" (so mixed load/charging on battery will give confused readings)
    • Battery Monitors (Like Trimetric)
    • Victron is another good brand of battery monitor
    • Midnite for some of their charge controllers has an electronic board for a standard battery shunt which will integrate battery State of Charge/usage/charging with the overall solar data
    For smaller systems, spending money on "not cheap" monitoring systems sort of tells you what you already know. Would you be better off spending the money on more solar panels/upgrading other system components?

    Don't get me wrong, I believe battery monitors are very nice to have--But they will not give you any more energy for your loads.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SulfatedPlates
    SulfatedPlates Registered Users Posts: 5
    Re: Is there a way to measure total watts charged for the day?

    Bill you raise good points and have great links; thanks.

    I am just hoping to maintain as much in watts as out watts, and have no way to measure the former
  • AceNZ
    AceNZ Solar Expert Posts: 104 ✭✭✭✭
    Re: Is there a way to measure total watts charged for the day?
    Is there a way to measure total watts charged for the day?

    If by "total watts charged" you mean watts used to charge the batteries, then you can use a battery meter to measure that.
    But now i need a way to determine how many watts I received from the sun each day, to match with the killawatt (watts out.)

    Watts received per day from your panels can be measured with a wattmeter. Most solar inverters have one built-in. If yours doesn't, it's straightforward to add one on the AC output of the inverter.

    Keep in mind that these are two different things. Energy out of your panels won't be the same as energy used for charging the batteries.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Is there a way to measure total watts charged for the day?

    Many charge controllers can monitor daily watt harvest, and if your inverter also logs loads, the difference is what went into your batteries.
    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

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