How to build a solar rack system for FREE, almost.
Once you’ve got solar panels now you need to mount them onto a frame or rack. Commercially available solar panel racks are expensive. This article shows you how to build your own solar panel rack for nearly no money.
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You can build the racks out of almost any material you have. Aluminum is ideal because it’s light and resists oxidation (rust), but it is costly. This article is a low budget plan and will work just fine. The downside is that it will need to be replaced at some point down the road. You should be able to get a decade or so from it.
- Materials and Tools
- Frame construction
Materials and Tools
I used salvaged lumber, and 3” exterior screws for these solar panel racks. That’s it. If you’ve salvaged the lumber and you already have the screws on hand then this project will be free. That’s right it won’t cost anything to build your solar panel racking system.
I built these racks from salvaged 2 x 4-dimensional lumber.
Click the image below to read an article on where and how to get free or really cheap building materials.
You will need a screw gun, circular saw, and an angle finder.
The angle you will need to find is the angle of the sun relative to the horizon so, you’ll need a gravity type angle finder. You can order this directly from Hardware World and have it shipped directly to your door. Click the picture below for the current price.
The first step is to measure your solar panels. To get the correct measurements you need to install the mounting brackets on the solar panels. The height of the rack doesn’t have to be the full height of the panel, but it does have to be tall enough so that the mounting brackets attach to the rack.
Now measure the width of the panel including the mounting brackets. This measurement will tell you how many solar panels you can fit on one rack and will be dependent on the length of the lumber you’ve managed to get.
For this project, The longest 2 x 4s I had were just under 8′ long. This allowed me to build a rack that holds three solar panels. The system being designed has six panels so, I built two racks for the solar panels.
The first step in building the frame is to build a basic box. The height will be the measurement from the bottom of the solar panel to the top of the upper bracket on the solar panel. The width will be the measurement from the mounting bracket on one side of the solar panel to the bracket on the other side of the panel multiplied by the number of panels that will be mounted to the rack that was determined by the longest length of the lumber available to you.
Next, the inside runners that are used to attach the solar panels where two panels butt up next to each other need to be cut and attached to the box frame. Measure the distance between the top board of the box to the bottom board of the box and cut a 2 x 4 to that length.
Install these boards at each point where two panels meet. Turn these boards flat and install them flush to the top edge of the box frame. This gives plenty of space for the two brackets of each adjacent panel to be mounted.
Now it’s time to build the base of the rack system. This is when you will use the angle finder. The correct angle to build the rack will depend on your location on the planet.
The number you want is your Latitude. Go to https://www.latlong.net/ and type in your city and your Latitude and Longitude will come up. The Latitude given is the angle you want to use.
Side Note: If you are planning a rack system that can be tilted up and down for maximum efficiency of your panels from winter to summer then you ad 15 to the Latitude for winter angle and subtract 15 from Latitude for summer angle.
With the box frame on the ground and the angle finder sitting on top of the side board of the box frame lift the top edge up until you get to the determined angle. With the top of the box frame suspended at this angle you now need to take two measurements.
1st is the distance from the top of the box frame straight down to the ground. This will be the two braces at either end of the base.
2nd is the distance from the bottom of the box frame on the ground back to where the braces will meet it at the ground. You will need two boards cut to both those measurements. Now construct the base by attaching the two end boards to the long board that was the length of the rack plus 3”.
At this point, you can attach the box frame to the base and it will be at the angle needed for most efficient use for a static solar panel rack system.
Mount the panels to the rack and you’re all finished.
The cost of a solar system can be expensive. If you’re on a tight budget you can build your own rack to reduce the overall cost. If you can salvage the lumber and already have screws or nails this rack will literally only cost you the amount of the electricity to build it.
Check out how to install the rest of this inexpensive 600w solar system here. https://offgridmaker.com/2020/03/17/how-to-install-a-600-watt-solar-system-on-the-cheap/