While researching the solar power off-grid system for my Shed-cave, one of the things that captured my attention was the angle or tilt of the solar panel. I wanted to know why they had to be tilted (Curious George) and what was the correct angle of tilt. I quickly discovered that while being flat 0° the panels will still produce electricity. However, mounting the panels with a tilt increases the electricity produced because of the angle in which the sun rays hit the panel.
PLEASE NOTE: The orientation of the panel is very important. A tilted panel faced in the wrong direction will not produce the energy required. If you are in the northern hemisphere, panels need to face true south, not magnetic south. If in the southern, panels need to face true north (not magnetic north). Panels are to placed were little to no shading can occur.
I also discovered that you can have fix tilt; adjustable tilt; or a solar tracker mount. The solar tracker is the most efficient of all. It tracks the sun's movement across the sky capturing almost 100% of the sun's energy (Oh Yeah!). This, of course, is the most expensive $$$ of all to set up and to maintain (Oh No!).
Which leaves me with the fixed tilt or adjustable tilt.To be honest, all the information gleaned give the adjustable just a slight edge (around 4-6%) over the fixed.
Step 1: Materials
So why build an adjustable mount? The premanufactured ones cost too much or is it because it is more challenging and fun to build one. Maybe because every little energy I can get counts so I can to stay a little later in Shed-cave. Could it be just for bragging rights (just to say I built one)? Whatever my motivation was (duh) it was settled. The panel had to be mounted on an adjustable mount.
Materials Under $100
- 1. 1 Set of roof mounting Z-bracket ($8.99)
- 4. 2X4x8 pressure treated ($13.88)
- 1. 4x4x8 pressure treated post ($8.98)
- 1. Carriage bolt with washers and nut (galvanized). ($4.04)
- 1, Galvanized heavy duty hinge $7.97)
- 3. Bags of concrete mix (I used a combination of fast-setting and regular 60lbs). ($11.44)
- 2. Galvanized corner brace ($6.36)
Some gravel; exterior screws (1.25; 2.5 and 3.5 inches), and strips of wood to plumb post and set concrete ($30).
I had some of the materials already so my cost was around $50.
Step 2: Tools Needed
- A post hole digger (powered or manual) and spade
- Circular saw or hand saw
- A regular drill (+ optional Impact drill)
- A level
- Tape measure
- Drill bit a little wider than carriage bolt
- Speed square (optional)
Step 3: Installing the Post
As a rule of thumb (not index finger), a 4x4x8 ft post needs to be at least 2 ft deep and 1ft wide for proper stability. Dig a little deeper to accommodate the gravel (about 2 - 4 inches) that I recommend pouring at the bottom of the hole. This facilitates drainage
- After the hole is dug, pour gravel and use the post to tamper it
- At the end of the post which will be inserted in the ground, I typically screw in a few screws. In my mind, it helps the post to adhere (maybe someone can tell me the science, if any, behind it)
- Insert post and plumb it (be certain to position a face of the post in the same direction as you have determined for the panel) and use braces to keep it straight
- I chose to use fast-setting and regular concrete: 1. I didn't want to wait the 2-3 days for the concrete to cure before installing the mount. And 2. I have seen where fast-setting mixes didn't hold up as well as the regular
- I framed around the post (optional) and add mix until it reaches desired height (above soil level)
- Slope the mix, as it cures, away from the base of the post for proper drainage
For additional information on wood post setting, you can try Wikihow.com.
Step 4: While the Post Set
Let me first apologize for not having actual pictures of the actual process. This instructable was after the fact.
Determine if you want the panel to be mounted vertically or horizontally. I was told it does not matter. I chose a horizontal mount.
- Install the Z-brackets to the panel
- Measure the distance from the top of one Z-bracket to the bottom of the other on the longest side, then measure across the panel from the end of one Z-bracket to the other. You can make the measurement wider or longer as I did
- Cut 2x4's according to the measurements (two for each). Label long side V1 and V2; and W1 and W2 for the others
- If mounting vertically, place V1 and V2 on top of W1 and W2. *1-Align corners flush; predrill screw holes close to the inside edge (This leaves room to attach the panel without hitting frame screws). Join frames using 2.5" screws. Fig 1
- If mounting horizontally, place W1 and W2 on top of V1 and V2. *1-. Fig 2.
- At this point, you should check the position of the panel on the frame. See where screw holes will be; and, as in my case, you may have to bore additional holes in the mount. Predrill holes but don't attach panel as yet.
- For the vertical mount, center the heavy-duty hinge on W1 and attached hinge. For the horizontal mount, center the heavy-duty hinge on V1 and attach hinge
- I found a T-Type hinge at HD, make sure that the top of the T is attached to V1 or W1. Fig 3
Step 5: Installing Frame and Tilt Lever
One day later, I attached the frame to the post. You will/may need some help at this point. I used the 3.5' screws for max depth. The knuckle of the hinge was attached slightly above the post for the maximum upward swing.
- Let frame fall to post and use a speed square (or any straight edge) mark the edges of post on V2 (W2)
- Predrill two holes 3/4 inch from post markings on either side. This places the screws in the center of 2 x4's
- Place 2x4x10's on both sides of post and attach to V2 (W2) using at least a 2.5" screw (Don't cut 2x4's until the tilt is calculated) See Fig 4
- Attach the corner bracket (optional) for reinforcement
Step 6: Attaching Panel and Calculating Tilt
Attached the panel using the supplied bolts from the Z-mount or 2.5" screws.
Now you can decide if you are going to use the 2 seasons adjustment or 4 season adjustment
For 2 season adjustment, most data suggest adding 15° to your latitude in winter or subtracting 15° from your latitude in summer.
You can easily find out your latitude at mynasadata.larc.nasa.gov/latitudelongitude-finder/
I came across a website that gives all the calculation and seasonal adjustment for a more precise tilt: solarpaneltilt.com
Step 7: The Final Countdown
Google pay store here I come. Download any app that can be used to find angles.
- When your angle is found, mark the place on the 2x4's where you have to drill. This is where you can use the optional clamp if your assistant is M.I.A. as mine was.
- Drill holes through and through for each angle mark
- You can label each hole by the season or just note the °
- Install the carriage bolt, washer, and nut.
- Cut off excess 2x4's
In my case, I will have to change the tilt lever for the summer month incline.
I'm also thinking about placing a horizontal brace from the tilt lever to the post for additional support.
I believe this can also work with a metal pole. The hinge could be connected to a 2x4 and the 2x4 connected to the pole via U bolts.
I hope this was helpful in some way. Feel free to share any tips or ideas on how to make this better.