NOTE: the longer the panel that is exposed to the sun the hotter the air gets as it rises.
Let me explain on this page, so you understand why these panels work:
At the bottom of the panel the air will enter at room temperature and be lifted through the panel (hot air rises)... as the heated air rises, it is exponentially being heated the more it travels before exiting the panel. Additionally, the black Cinefoil is very thin which heats quickly even on days where the sun goes in and out. The longer the panel is exposed to the sun, the better it will work.
The black Cinefoil is THINNER than pop or beer cans... THAT is why these panels work so well. If you use thicker materials than the Cinefoil, by the time that material is heated enough to be beneficial, the sun may get covered again by a cloud and the panel will have to start all over again when the sun comes back out.
This panel is only 3/4 of an inch thick and weighs in at less than a couple pounds.
On a partly cloudy day the black foil collector reached about 150 degrees (during the sunny times) and on days where the sun was without a cloud in the sky, the foil reached 185 degrees. The plastic film on the front of the panel only felt warm to the touch and the aluminum flashing on the back of the panel only made it to 98 degrees.
In the video below, it was an overcast day and when I took a temperature reading... it was actually reading the plastic film which was still 143 degrees.
This type of solar panel (like most) only work if you have larger south facing windows or patio doors (which are better); and of course, a little sun helps. But the nice thing about these panels... They are VERY easy to make and hang "INSIDE" your window where you don't need to concern yourself with zoning codes or big ugly boxes hanging on the side on your house. A plus, you can take them down in the summer; also, because of their design... you can use these in apartments and condos.
The panels use no electrical or mechanical parts and they work awesome as the air is super heated through back chamber of the panel and exits out the top as if there were a blower in the panel.
To aid the distribution of the heated air that exits the panel, add a small fan (on a low setting) to circulate the heated air from the main room to other rooms in each doorway. DO NOT add a fan to blow through the panel itself... that will only serve to force cool air through the panel and not allow the air to super heat as it rises through the panels chamber.
Yet another option... turn your thermostat's fan to on so the furnace fan runs all the time; this will allow for the best circulation throughout the house... put it back to auto at night.
The only hard to find part of this panel is the Cinefoil which can be bought from my website RedbarnCrafts.com
Additionally... by using the Cinefoil, your panels will look more professional!
Check out these videos before starting the project. I explain (AND SHOW) how functional these panels really are.
Let's get started...
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Materials
Materials needed for the Window Solar Panel:
1. Screen frames and framing Corners
3. Aluminum flashing
4. Black Cinefoil
5. Heat resistant aluminum tape
6. Window treatment film (comes with double sided tape)
7. Suction cups with #10 eye screws
10. Optional two soffit vents (not shown)
Step 2: Basic Tools Needed
- Riveting tool
- Drill (size bit for rivets)
- Marking pen
- Measuring tape
- Needle nose pliers
- Hole punch
- Heavy duty scissors
- Light duty scissors
And of course, a hair dryer to shrink the window film... if you are one of those super-observant people watching my videos... you will see, I don't need the hair dryer :-)
Step 3: Building the Frames
So that your cuts make for a square frame for you solar panel... tape together four lengths of screen frame.
NOTE ------ make sure you size the frames to fit the width and length of the aluminum flashing and Cinefoil.
Step 4: Building the Frames
After cutting frame pieces to size, insert the plastic corners.
Step 5: Building the Frames
Step 6: The Aluminum Back of the Panel
Measure and cut a piece of roof flashing from the roll to your desired length.
NOTE --- UNDERSTAND --- the longer the panel that is exposed to the sun the hotter the air gets as it rises. To explain: at the bottom of the panel the air will enter at room temperature and be lifted through the panel (hot air rises)... as the heated air rises, it is exponentially being heated the more it travels before exiting the panel. That is why these panels work so well.
After marking, position a straight edge and tape it down.
(Yep, a utility knife will cut flashing with a few passes)
Carefully cut the flashing.
Step 7: The Aluminum Back of the Panel
Mark the ends of your cut to size flashing for the vents you desire to use. Then use a heavy duty hole punch to make your vents.
Step 8: Preparing the Cinefoil Panels
Use the aluminum flashing you already cut to size for sizing the foil by simply using it as a template.
Step 9: Preparing the Cinefoil Panels
Use a utility knife to cut foil to length and width.
Step 10: Start Assembling the Panel
Align the flashing to the frame and start the taping process for the back of your panel by using "SMALL" pieces of the aluminum tape about every 12" or so. Apply tape to the centers of each end and side. Tape each corner as shown.
The flashing is pretty much a super lightweight stiffener and if you cut it square... your panel will be square.
Step 11: Attach Stiffeners
Position stiffeners to make sure a clear channel is maintained through the heating chamber. There purpose is to keep the channel between the Cinefoil and the aluminum flashing clear to allow the air to move freely.
The stiffeners are just the cut off pieces (left over's) from the framing pieces cut to size. The plus side is... you are not wasting anything when it comes to the frame material.
Tape the stiffeners down.
Step 12: Attach Stiffeners
Drill two to three holes through each stiffener and the aluminum flashing.
Turn panel over and start riveting.
After all rivets have been inserted, turn panel over again to prepare for the foil.
Step 13: Applying the Cinefoil
Center the Cinefoil and tape it to one end of the panel in the center... this will allow you to attach the Cinefoil to the other side keeping it square on the opposite side.
Step 14: Applying the Cinefoil
After the Cinefoil is aligned, tape both corners on one of the ends, then repeat on the opposite side.
After all corners are taped... finish spot taping at every 12" or so.
Now you are ready to apply the second frame.
Step 15: Attaching the Window Frame
The aluminum flashing and the Cinefoil is what forms the heating chamber. Now attached the second frame to form the window of the panel.
The second panel MUST be attached on the same side as the Cinefoil.
Attach the second frame the same as you have the aluminum flashing and the Cinefoil to the first frame. Tape one end then the other and place tape again about every 12" or so.
The window also allows the Cinefoil to heat without losing any of that heat to the air around the panel. Without the window, your panel will NOT work efficiently, much like the little radiant energy your carpeting, furniture or anything else in the room that catches the suns rays.
Step 16: Apply Double Sided Tape
On the Cinefoil side (which is the window side as well) apply the double stick tape around the entire perimeter of the panel... overlapping is good, but keep the double sided tape "on top" of the frame as shown.
Step 17: Preparing the Window Film
Cut the window insulation film just a littler larger than your panel. Tape one side of the film down on a floor (I am using a cafeteria table), pull each corner of the film until the film is as flat as possible... the wrinkles will be taken care of later with the hair dryer.
Step 18: Applying the Window Film
With the window film taped on the floor (or table) place the panel (Cinefoil side down), press around the perimeter of the frame against the window film to make sure you get a good bond on the double sided tape.
Step 19: Removing Excess Window Film
Cut the film as close as possible to the frame of your panel and remove it to prepare the panel for the final taping using the aluminum tape.
Step 20: Preparing for Aluminum Tape
Cut two pieces of tape for each side. Over-sizing is good... you can trim the excess window film after it is applied.
Step 21: Applying the Aluminum Tape
In the first photo, you will align the tape with only a short piece of the tape having its adhesive exposed. Press the exposed tape down and grab the tape backing pulling to remove it; HOWEVER, do not allow the tape to touch yet.
Holding the tape slightly up from the frame, use your fingers to brush back as you press the tape down. This will result in a very clean application.
Step 22: Applying the Aluminum Tape
As you apply the aluminum tape, flip the panel up to wrap the tape around the back finishing off this process.
Step 23: Shrinking the Window Film
Now for some fun (at least I think so). Use your hair dryer to shrink the film finishing off the panel.
Step 24: Final Step - Suction Cup Hangers
Drill each corner with a 3/32 bit for starter holes.
Start the eye hooks by hand.
Carefully run the eye hooks down with a special driver bit. If you use any other tool
be careful to not scratch the film.
As you can see, the eye hooks accept the window suction cups well.
Step 25: Success... the Finished Panel !!!
Thank you for reading my Instructable... If you take on this project, I think you will be very surprised and happy with the results.
It has been a while since I first uploaded this to the Instructable website. I have more, and since I am now settled in to our new home... I hope to have more for you soon. Please consider to follow me on Facebook where I share stuff everyday.
Participated in the
1 Person Made This Project!
Dustin Rogers made it!