Small Solar Off Grid System

Discussion in 'Post Your Photos' started by Andy R., Apr 17, 2013.

  1. Andy R.

    Andy R. WindyNation Engineer

    We've had an off grid cabin for 20 years. I installed a CB radio and powered it with a 4.5 watt solar panel to a car battery. Since the panel was so small, it didn't need a controller. First battery lasted 13 years and the 1st panel lasted 17 years.
    Here's the panel.


    So this week for a few hundred bucks, I took the plunge. Bought 2 Windy Nation 30 watt solar panels, a Morningstar controller, and a Harbor Fright inverter. I had some outlets in the cabin floor which I had used with a generator so I hooked them to the system.

    Why two 30 watt WN solar panels instead of their 100 watt panel? The 100 watter had better cost per watt but my goal was to give the panels some protection under the roof eve because sometimes the roof is covered with snow for over a month in the winter and I don't get out there for weeks. They were just a better size.

    Why did I go for the Morningstar controller? I looked at a few and the morningstar opperated in sub-freezing temperatures. A lot of them only opperate down to 32 degrees. This one called the "Sunlight" has neat feature with 10 settings to run 12 volt lights or whatever. An example of the settings would be, comes on at dusk for 4 hours turns off and comes on again for 2 hours at dawn. I bought a cheap volt meter on ebay that I hooked up to a push button to avoid running the batteries down and also hooked it up to this Sunlight feature so the meter automatically turns on at dusk for a few hours.

    I bought the Harbor Fright inverter because their reviews seemed okay and I got 1500 watts for 130 bucks. Seems to work okay but the fan is always on making noise and using power and causes total square wave static in the CB radio even when fully squelched. I won't have it on all the time.

    I'm using 2 car batteries that a 6 years old so when the 1st one quits, I'll go to Walmart and get 2 Marine deeper cell batteries.

    Here's the panels:




  2. Minnesota

    Minnesota WindyNation Engineer

    Nice job! Do people actually use CBs anymore? Nice cabin!
  3. Andy R.

    Andy R. WindyNation Engineer

    You're right Minnesota about CB radios. The cabin is 11 miles from my house so I can radio home if the skip isn't too high. The cabin gets no cell phone service but that's okay.

    Nice to see ya back around here.

    Here's what I mean about snow on the roof.

    Minnesota likes this.
  4. Andy R.

    Andy R. WindyNation Engineer


    Swapped out the 1500 watt 129 dollar Harbor Freight square wave inverter for a 300 watt 279 dollar Morningstar "Suresign" pure sign wave inverter. The Harbor Freight quit working and since 95% of the time I only run lights, I thought that a pure sine wave would make my lights last longer. I already blew out a CFL in less than 30 hours.


    This smaller 300 watt is more "industrial" like and is" hard wired" to the panel box. It also has no cooling fan. Being outdoors the fans often get "cocoons" or something else in them and often the fans are the 1st thing to fail. With the inverter mounted underneath the Cabin floor, the wood acts like a sounding board on a guitar and the whole cabin had a small hum. The new inverter is totally silent.

    The square wave inverter made our CB radio totally nonuseable. When fully squelched it still buzzed really loud. Although the new inverter does make a small buzz, the CB is now useable.

    The Harbor freight should be mounted inside a vehicle or building and is only rated down to 32 degrees F. The Morningstar is suitable for marine environments and is rated down to -40 F.

    The Morningstar is on constantly and has a standby mode to keep it from running the batteries down. When there is a wattage draw of 8 or more watts, it wakes up and starts running. I just turn on a light switch in the Cabin and the light comes on just like at my house. The current draw when the inverter is running is 450 miliamps. In standby mode it's about 55. You can install a remote switch to shut it off if you'd like to and I did to use as an emergency shut-off.

    TomT likes this.
  5. leamywind1

    leamywind1 WindyNation Engineer

    Hey And, very nice. I like the way it is all so compact

Share This Page