Blog > Preparedness > Our Simple DIY Home Solar Power System RSS

Our Simple DIY Home Solar Power System

Raised Garden Beds in the Eartheasy Store

Join the Eartheasy Community

Sign up for our Newsletter:

* indicates required

This basic off-grid solar power system is simple to install and can be easily expanded…

By Greg Seaman, Posted Jul 18, 2012

DIY Home Solar power system

Bringing some of the benefits of electrical power to our off-grid home has been a hit-or-miss affair. Over the years we’ve tried some very simple approaches to lighting and small battery recharging for our flashlights, such as hauling a 12 volt car battery to a small rural school about a half mile away every time it needed to be topped up. This was time consuming and inefficient. But we didn’t want to lose the feel of our simple home by bringing in a large generator and the jugs of gas needed to run it, and the prospect of setting up a wind turbine or solar array seemed expensive and a technological eyesore in a natural setting.

…developing using a dialup internet connection on a phone line strung through the woods was challenging…

For many years we managed to get along without the conveniences which electricity can provide, but developing using a dialup internet connection on a phone line strung through the woods was challenging, and charging my laptop became a regular necessity. A few years ago, wireless broadband was introduced to our area, and the promise of high-speed internet was the stimulus we needed to build our own reliable, affordable and simple “do-it-yourself” alternative energy system.

Today, with the help of a local expert on off grid home solar power and alternative energy systems, we have the best of both worlds. Our basic solar powered energy system provides more electricity than we expected, it has been very reliable and maintenance-free, and it is almost entirely hidden from view. A solar panel on the roof with a few wires leading to a small battery bank powers my laptop, and a radio mounted on a tree for receiving the wireless broadband signal. The system also provides enough energy to charge several small power tools, run our home sound system and, amazingly, power a full-size chest refrigerator year round.
solar battery bank
Our simple home solar power system is comprised of four basic components: a solar panel, a charge controller, two 6-volt golf cart batteries and a small inverter. My son and I were able to install the system in a few hours, and there have been no maintenance issues other than checking the fluid level in the batteries every few months. The cost of this complete solar system, in today’s pricing for the components, was less than $1000.

The cost of this complete solar system, in today’s pricing for the components, was less than $1000.

We have already enjoyed about three years of trouble-free use from this system. The refrigerator has not been off for over two years, which is pretty impressive considering we live in the Pacific Northwest where the short winter daylight hours provide minimal solar exposure for the panel.

About the shadows on the panels: Our solar placement is the best we could manage since our home is nested among trees. The shadow you see in the image above passes over the panels in about 30 minutes. We’ve chosen to accept this small decrease in collected energy in favor of the trees which we don’t want to cut down or top. If our electricity needs increase, then our system will be moved some distance from the home where there is more available sun. The ideal solar installation, of course, would have no shadows crossing the panels at any time.

The basic components of this off grid solar power system are as follows:

1. Solar panel

We have a single solar panel mounted on the roof of our home: a 123 watt Sharp Photovoltaic Module, model 123UJF. The panel is equipped with a permanently attached junction box for ease of installation of wires and conduit. Two boards are lag screwed into the roof and the solar panel is bolted to the boards using wing nuts, so it’s easy to lift if maintenance is required. The panel surface is about 5” above the roof surface. The panel is hinged to the mounting board, which allows the panel to be tilted towards the sun, and to increase ventilation. We plan on adding a cog/string system to make it easier to tilt the solar panel towards the sun from the ground. Two wires run from the solar panel, one is the power line and the other is a ground line. The power line runs down the roof to the charge controller, where there is a fuse. A box on the porch which houses the charge controller, inverter and batteries. The ground wire runs beneath the house and is attached to a rod which is driven about two feet into the earth.
solar panel
It should be noted that the panel guidelines state that the installation of PV modules requires a “great degree of skill and should only be performed by qualified licensed professionals, including licensed contractors and licensed electricians.” We installed our system ourselves because our supplier, who is a licensed installer, gave us explicit directions and came by to inspect the installation after it was done. We suggest that you follow the recommendation as stated in the module instructions with regard to installation.

You may notice there is a shadow on the panel being installed in the picture above. This shadow crosses the panel in about 20 minutes, so there is a small loss of efficiency over the course of a day. But we live in a beautiful forested area and I value the tress more than 100% efficiency in solar gain. If there were a major solar loss I might top the tree, but our system provides for our needs and so we will live with the shadow, for now at least.

The cost of the solar panel in today’s pricing is about $425.

2. Charge Controller

We use a Trace C12 Charge Controller which automatically adjusts the amount of power running into the battery. The controller has a small LED light which indicates the state of charge so it’s easy to see when the batteries are fully charged or if they are becoming depleted. The light flashes either red or green, with multiple flashes indicating the status of charge at any given time. We can see that if the light is red we should reduce our power use, and if the light is green then we have the power needed to charge or run additional devices.

charge controller

The cost of the Trace Charge Controller is about $90.

3. Battery Bank

Two 6-volt golf cart batteries are wired in series for a 12 volt system. Each battery is rated at 232 amp hours. The batteries are enclosed in a wooden chest with hinged lid, and the top panel of the chest is removed to provide plenty of ventilation. The battery posts and connections are kept clean, and periodically checked to ensure good connections.
solar batteries
battery box
The cost for the two batteries was about $400.

4. Inverter

The final piece of the system is a small inverter which converts the 12 volt DC power into 120 volt AC power. This enables us to use standard electric devices without the need for adaptors. Inverters are available in a wide range of wattages for different size systems. Ours is a small inverter made by Nexxtech, rated at 300 watts, with a 500 watt surge capacity. It comes with two cables, red and black, with alligator clip ends for gripping to the battery posts. In choosing which size inverter to buy, we calculated how much power was available to our system and what devices we wanted to run. In calculating power needs, it is important to add the power requirements when two or more devices are running simultaneously.
solar inverter
Our Nexxtech 300 watt inverter cost about $30.

What this system provides:

An alternative energy system can be used to provide electric power to any number of electric devices, such as appliances, tools and computers. The bigger the system, obviously, the more power it will provide. To give you an idea of the capacity of a small system like ours, here is what we use our solar energy system to power:

solar powered refrigerator
This is a DC powered refrigerator, the same size as a conventional chest freezer (4’ wide). The refrigerator draws 40 watts of power and can be converted to a freezer by replacing the thermostat. Since the refrigerator is a DC model, it is wired directly to the battery, bypassing the inverter. So the refrigerator keeps running even if the inverter is turned off. Our refrigerator has been running continuously for over 2 years without any problems. Even during the dark days of winter, the unit has adequate power to keep running.

vers sound system This is our Vers sound system which lets us use an iPod or direct cable from an iPhone or computer to deliver a rich sound while drawing relatively little power. We can run this sound system about 3 hours a day in winter, and as much as we want in summer.

solar powered laptop Our solar system provides adequate power to run a laptop computer all day if necessary. We also run a router from our inverter so that multiple computers can be operated at the same time. In addition to the router, a small radio is installed on a tree about 300’ from our house which receives the wireless broadband and transmits the signal to the house.

Besides the laptop, we have a battery-powered driver-drill, which is a very useful tool. Our system recharges the battery for this tool in about 30 minutes.

These are the principle applications we use which are provided by the solar power system described above. However, you can use a wide variety of electric devices as needed. Today, we enjoy the benefits of our system without feeling a technological intrusion into our off-grid homestead and lifestyle. The refrigerator especially has made a big improvement in our day to day living, since storing food is so much easier. Over time we may expand our system by adding more batteries for storage, and eventually a second solar panel or small wind turbine.

Bringing electricity to rural locations is something of a balancing act since we don’t want our simple lifestyle changed by too many electrical gadgets. It does require some restraint to keep things simple, but the few electric amenities we now have are most appreciated!

Related Articles

Our Experience with a Solar Powered Refrigerator
4 Mistakes to Avoid for the Novice Homesteader
Our DIY Off-Grid Fire Protection System

Greg About Greg
Originally from Long Island, NY, Greg Seaman founded Eartheasy in 2000 out of concern for the environment and a desire to help others live more sustainably. As Editor, Greg combines his upbringing in the cities of New York, Boston and San Francisco with the contrast of 31 years of living ‘off-grid’ to give us a balanced perspective on sustainable living. Greg spends his free time gardening, working on his home and building a wooden sailboat with hand tools.


Posted in Preparedness Tags , , , , , ,
  • Your comment seems so familiar. You’ll do fine and will enjoy your energy independence. We’ve had great results from our Sundanzer fridge, which is easy to convert to a freezer. Very low wattage, runs off a single 127 watt panel, has been running steady for over 4 years. This is a full size chest unit.

  • Francisco Turalba

    This is perfect for my needs GREG. Thanks. I am from from the Philippines where we have more than enough sunshine and heat! Airconditioners are a must!

    Greg , I wonder if you can advise me on how and what kind of set up I need to install to run two or three split type AC’s. Two horse power per AC. That’s on top of the rest of my power needs like light, ref, power tools & PC’s. We don’t have TV. In short I want to be totally off grid.

    Thanks again GREG. You are a blessing to mankind! 🙂 if I can do this I am sure I can convince my friends to have one installed in their homes. Business oppurtunity for us Greg?

    • Hi Francisco,
      Thanks for your comments. The costs and options for solar arrays, inverters and charge controllers keeps dropping, and I am not an expert on recommending systems. You’ll get better advice from your local solar provider who will know what options are available in your area, as well as the ideal configurations. You just need to bring them a list of your energy needs.
      Yes, there are certainly business opportunities in this field – renewable energy is ready for wide use in the general population.

  • greener1122

    This approach is very workable and what I developed is similar, utilizing one large panel, deep cycle batteries, inverters, a charge controller and the peripherals that allow everything to be hooked together and inserted on or within a snug battery box.There is about 2000 watts output which will indeed power up most household appliances (except air conditioning and electric heaters–such as a garage door opener, skil saw, medium sized fridge, coffee pot, any electronics, vacuum cleaner etc.–for hours if not days, depending on location and draw.

  • jonelle

    Thank you for information! I used to live in Ronkonkoma ny. But now live in sunny Texas. This solar way is the way I am going. I already purchased a system, just need to install. But I am concerned about EMP’s. What do you suggest???

    • The panels will likely be ok but associated wiring and charge controller may be affected during a surge. Some suggest isolating the charge controller in a metal box or can, you would have to do a little research to find the best solution.
      In a simple, inexpensive system like ours, I find the best solution is to keep a spare inverter and charge controller. They are easy to replace.

  • Kandee Lynn Urseth

    Greg, We are building a 700 ft off grid home that will use solar for a chest freezer, some lighting, an energy efficient ceiling fan as necessary, charging some electronics such as laptops and flip cell phones, run an LED HDTV a few evenings a week, etc. We have calculated that we should do well with a 1500 watt, 24V system. What we are struggling with is piecing it all together and knowing with certainty what components will make our system the most effective and efficient. i have read many blogs and thought I had it all pieced together, including a 12V battery system. After talking to a solar distributor, we realized we needed 24V, the 1500 W of solar and a different invertor. He sent me with info on what to pick for the proper invertor and when i sent him the link of what i’d found, based on what he told me, he said that wouldn’t work either and directed me to one that was nearly 3 times as much money. We are overwhelmed by the amount of information that is very hard to make sense of. This blog has given me hope and info that I haven’t been able to find, but as your system is significantly smaller, I am having trouble converting it to what we want to do. Would you be kind enough to provide us with some additional information or direction on how we can purchase a system this size ourselves? We hesitate going to a distributor as we feel like they want to just make a sell and aren’t as concerned with our budget as we are. We really want to DIY if we can. Any suggestions?

    Thank you- Kandee

    • Hi Kandee,

      Yes it can get complicated with developing technologies and different opinions from experts. I am not an expert in solar technologies, and relied on a local solar installer for advice. You can get more information from forums on the web, where no one is selling you their system.
      The advice I would give is to start small and gradually expand your system as needs dictate. We managed for years with just the one panel, today we have three panels and a 30 amp charge controller. Keep it simple and after some use you’ll understand the process and know which component to upgrade as your electric needs increase.

  • Hmm, this sounds interesting.

  • Richard Powers

    I’ve recently bought a 26 foot Grampian sailboat which I plan to install a shower inside.. I find your comment interesting too, however, it seems the draw on the battery bank would be rather extreme no?.. Wouldn’t a tankless propane hot water be a better choice? Nevertheless, I’d be interested to hear specifics on what kind of 12v element you installed.

    • I have the same question. Maybe Dennis has no problem keeping his batteries topped up since he’s in a camper.
      Here we see a lot of tankless propane systems. I’m thinking of putting one on a sailboat under construction.

      • Richard Powers

        What kind of sailboat you get Greg?

        • It’s a 40′ wooden sailboat. Should be done in 2016.

  • James Ramidden

    This is super cool and insightful tips that can be used to help everyday life go so much easier. Thanks so much for sharing.

  • tiffjan

    Awesome and easy to follow write-up. I’m curious to know how the setup would be for an 805 watts/day vending machine. Can you make any suggestions?

    • I’m not enough of an expert to advise you on this. Call your local solar provider, they’ll have the best answer for you.

  • Its amazing how these solar batteries can do. Now a lot of people would be using this in the future. Wish we could have this in our place.

  • Karen B.

    Thanks for the great article! Best one I’ve found while researching solar for a 40′ boat. I thought all I really needed was enough to charge phones/ipad and the coffee maker now I’m thinking I can have my freezer and maybe hot water (only a 6 gallon tank) too! Thank you!

    • Be sure to get a new or near-new panel for the maximum input. You should be able to run a freezer no problem. I’m also putting together a solar system for a 40′ sailboat, maybe we should compare notes.

  • Billy Abotane

    Really interesting post.I come from a remote village in Papua New Guinea which most of my people are off the main grid.I just need to do more research to assist my people who have been without electricity for ages.

  • Our panels (we now have three) held up fine through the winter. However we did have an intense thunder/lightning storm that fried the inverter. I should have thought more quickly and disconnected it.
    Cooling is not much of a problem, we do not have a fan or A/C. It hit 90 degrees yesterday, so we just slow down in the afternoon and stay in the shade.

  • Many people are resistant to having solar panels installed on their homes because they believe the installation costs are too high. Initial installation costs of residential solar panels vary depending on a number of factors.

    • It was easy to install the panel myself. Just follow the simple directions and connect a couple wires.
      Btw, this article will be revised shortly, as I’ve added two more panels, have a newer charge controller, and have a battery charger wired into the system. The revised article will explain all this.
      Thanks for you comment.

Blog > Preparedness > Our Simple DIY Home Solar Power System