Video 1 - Getting The Best Out Of Batteries

11 Comments

  • Jack Coleman

    November 29, 2016

    Will 2 L-16RE batteries BE SUFFICIENT with 200 watt mono/panels ? I've got to watch tv 14hrs a day . It's 65 watts. Do I do 12 ×370 = you know for the amp hrs.

    • Nick Meissner

      December 8, 2016

      Hi Jack, Thanks for your question. Sizing how many batteries and solar panels you need is something that requires more info. There are a number of calculations that must be taken into account. If your only load was 65 watts and was running for 14 hrs per day, you could do 65 x 14 = 910 watt hours. The L-16 RE-B holds 370 amp hours at 6 volts. 370 x 6 = 2220 watt hours per battery x 2 batteries = 4440 watt hours. Batteries are only 80% efficient so the capacity is effectively 3552 watt hours. If you want to discharge your batteries to 50% then your new effective capacity is 1776 watt hours. So you would have almost 2 days of capacity in 2 batteries if that was the only load you ran. Of course there are other inefficiencies too but that gets you close. The system design calculator that I refer to in video 4 makes quick work of doing this and all the solar calculations. Hope that helps!

  • Jon McElhaney

    December 9, 2016

    What model number forklift battery are you using? I am helping a friend that has 3 banks of l16 6v Trojans. They are no good, so we are exploring options. If we went with the GB 12-100-13, and they hardly use any power (e.g. 1 light at night from 6pm to 9pm, watch TV 3 hrs a night, propane fridge, gas dryer, washer 1 load every few days) Would this be sufficient? They have outback stacked inverters, 1 mppt 60 charge controller, generator and 4 120watt panels (old and way undersized,we know). We want to do the batteries and upgrade to 4 255 watt panels. Any thoughts? They don't have a lot of money, but are willing to spend some to upgrade. Also, thanks for your video! Great job!

  • Jon McElhaney

    December 9, 2016

    Correction to my last comment, we will be getting 6 255watt panels.

  • Teodor

    April 15, 2017

    Thank you Nick!
    You are great!
    I admire your work!

  • California Twiddlebug

    June 2, 2017

    Hi Nick,

    I've always dreamed of going off-grid, but recently, California in some jurisdictions are going after people using off-grid solar and batteries to power their homes. I wanted to go off-grid in the city. I have heard it's illegal to disconnect from the power pole. I will be checking into it, but that it may be illegal is the only thing standing between me and taking your course. It seem ridiculous. I'm hoping if a person has a property a good distance from the utility poles that he or she can go off-grid! Hopefully, this link will stay up long enough to let you know.. I'm looking into it.

    • Nick Meissner

      June 2, 2017

      Hi there,

      If that is the case, my guess is that it would only be in some larger cities, but since I haven't heard about the specific thing you are referring to, I can't say for sure. But even if it is "illegal" in your location to go off the grid, you still have some options.

      For instance, you could set up an off grid system and have it connected to the house through a "transfer switch". This is a very common piece of equipment that enables a backup generator to be connected to a home safely and easily. One could just as easily connect their off grid solar system to the transfer switch instead of just a generator. It would enable you to still be connected to the power company and you would treat the off grid system as an "emergency backup" just like you would a backup generator. How much of the time you run your home on the "emergency backup" is up to you ;-).

      That's just one possible work-around if you were in a location crazy enough to outlaw going off the grid (assuming that for some reason you decided you absolutely had to stay there).

  • Richard Moore

    August 13, 2018

    Thank you

  • Alan Loughman

    November 4, 2018

    When using a wind turbine . Say 3kw or 6kw ..can i use an inverter back to feed the battery or connect to fuzebox @240v ac . Or should i fit a smaller turbine@100watts

  • Angela

    March 3, 2021

    If you want to run an arc welder would you need 2 forklift batteries?

    • Lisa Meissner

      March 3, 2021

      Hi Angela,

      To run an arc welder, you would need to make sure that the system is properly designed to meet those demands. And the batteries are one component that would need to be sized for that, depending on how often you use the arc welder.