How to measure whole house load?

ligwyd
ligwyd Registered Users Posts: 210 ✭✭
in General Solar Power Topics #1
I have been told that a device from Efergy is a cost effective way of measuring your total power consumption over a period of time for the purposes of sizing a system.
What is the consensus here for doing just that? Any recommendations? Have a generator running everything right now but would like to know how much power is actually being used to start accurately sizing a system build.'



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  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    #2
    For under $100 you can buy a used utility meter, either pointer or digital, along with a meter base.  Wire it in, read the KWH.  Want to record genny & PV?  Wire two.  All pretty simple

    there are also CT metering schemes that would work as well, but probably not as inexpensive yet, but may be easier to install?

    Tony
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  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,167 ✭✭✭✭
    #3
    Tony, I agree - using Current Transformers will be waaaaaay easier to install. Get split core CT and the exposure to heavy power will be a few minutes.
    I just use the metering data provided by my local utility - including hourly.
    I always have more questions than answers. That's the nature of life.
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  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    #4
    For ~$50 I used a power recorder to log energy useage over a month, this one is rated for 3750W which is greater than the output of my inverter so doing whole house loads were possible in my case.
    https://youtu.be/qZ5FoI6qoXI
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #5
    TED has been around for a long time... And they have different models that can measure more than one circuit (main, water heater, A/C, etc.).

    http://www.theenergydetective.com/

    Just of an example of what is out there...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    #6
    Marc Kurth said:
    Tony, I agree - using Current Transformers will be waaaaaay easier to install. Get split core CT and the exposure to heavy power will be a few minutes.
    I just use the metering data provided by my local utility - including hourly.
    Mark,  do you have a brand/model you use?  Ihave a client that I need to do an analysis for with 15 water heaters and 15 clothes dryers.  The client has no idea of how much load these draw on a annual basis used seasonally.  As part of a broad audit I want to meter/log each device for a year.  I have not seen a CT system that is really affordable in quantity.  I have found some 240 vac pass through meters but that is a wiring issue, each one needs to be hard wired (and enclosed).  Failing that, I can buy cheap meter bases and cheap utilities meters for ~$35 USD for the pair.  That comes with an install headache and cost as well.  I might consider doing the water heaters one season, the dryers a second, so the hardware could be moved.

    Thanks,

    Tony
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