solar, batteries, inverters...oh my! Newbee how to question

Good Morning!

So before I ask my questions, let me paint a visual picture...

I have electrical service from the street that when it gets to the meter at the house it is split into two 220 services.

One service enters the house right there at the meter and feeds a panel for the older part of our house. The other service goes underground for about 40 feet to a panel in a basement that feeds a new edition on our house.'ve got the picture...two 220 services and panels feeding two different sections of the house... the old part and the new part.

We want to do something with alternative or wind...maybe both. And we also want to be thinking about something with storage batteries, but here is my question.

The basement where that second 220 service and panel is located would be perfect for a battery rack and all the associated equipment (e.g. inverter, etc.). However, if I put all the gear in the that location, how do I power the other side of the house?

While the other panel location is adjacent to the meter, putting an inverter and battery rack there isn't an option...the panel is in the family room and there isn’t a lot of room there for gear.

I've seen outdoor enclosures where you could put the gear outside next to the meter, but I imagine that decreases the battery life, etc.

Do I run a cable back from new basement to the meter location and tie in?

Looking for ideas!




  • jcgee88
    jcgee88 Solar Expert Posts: 154 ✭✭
    Re: solar, batteries, inverters...oh my! Newbee how to question

    It would be easier to advise you if you provided a bit more
    background information and tell us what you are trying to

    For example, are you trying to provide "ride through" for
    momentary power interruptions? If so, for how long do you
    need the ride through to last, and what is the minimum
    capacity you need during an outage? How often do you
    experience power outages?

    If your minimum capacity during an outage is modest and
    you don't get many outages per year, it might be far
    cheaper and simpler to complement a grid-tied solar array
    with one or more generators than to build a complicated
    solar/charger/battery/dual-connection facility.

  • BB.
    BB. Super Moderators, Administrators Posts: 33,442 admin
    Re: solar, batteries, inverters...oh my! Newbee how to question

    Also, having two services implies you may have some substantial electrical loads...

    Looking at your home, measuring loads with a kill-a-watt meter and/or whole home data logger (lots of choices for both), adding insulation/double pane windows, energy star appliances, smaller laptop vs desktop servers, updating heating/cooling/hot water with modern heat pump systems, etc. will all be a help with your power bill (probably less expensive than simply adding solar or wind power). And, if you are after emergency power, having fewer loads will help there too (off grid systems are very expensive--on the order of $1-$2 per kWH for pure off grid power used 9+ months of the year).

    Also, depending on where you live and what happens in the future, having to billing meters may be a help or a hindrance.

    In California, we have tiered rates... The more power you use, the higher the $/kWH rate (from ~$0.12 to $0.52 per kWH range).

    In other areas, the charge for metered service is not cheap, so if you do not use a lot of power, your two meters just being read and billed may cost you more than the power you use...

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: solar, batteries, inverters...oh my! Newbee how to question

    usually, in the case of a backups arrangement another subpanel is used to run the circuits to be backed up from the output of the inverter. if all of the circuits to be backed up are currently on the first service panel then the output of the inverter could be run into that area of the house where you could then disconnect those circuits on the service panel to go to the new subpanel mounted near the service panel. to make matters worse is those circuits may need to be junctioned to allow the wiring to reach the new subpanel. this can get complicated real quickly and to be sure you get this right, safe, and withing local inspector's requirements i'd suggest an electrician unless you are quite knowledgeable on it.
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: solar, batteries, inverters...oh my! Newbee how to question

    Because I know I will say it sometime in this thread,, I might just as well say it early.

    Please be advised that battery based PV comes at about twice the cost of grid tie, at about 1/2 the efficiency, leading to energy costs that are ~4 time that of grid tie,, as much as 10 times the cost of simple grid power. (Per KWH)

    The grid in most places is very reliable, so for outages, most find that their money is very much better spent on a generator to cover essential loads while the grid is down, and then spend their money on grid tie, which is a pretty efficient use of money (compared to battery based systems)

    A Bill suggests,, before you do anything, do all the conservation measures that you can find,, and then do a bit more. Spend your time reading, gaining a basic understanding of the detail involved in RE so that you can avoid the biggest single pitfall of RE,, that is the Ready, Fire, Aim syndrome.

    Welcome to the forum and keep in touch,