A few days ago we started writing about our DIY Solar Bag and today we start to show you how to make your own solar Bag ‘the easy way’. Part one is about the integration of a solar panel in a bag.
What you will need for this part of the project:
A bag. Either you transform one of your bags or you look for a new one that looks cool and has a design that makes it easy to integrate a solar panel. The later was the way we choose.
A solar panel. Our recommendation is the PowerFilm WeatherPro Solar panel 7.2 volt 200 mAh which costs $ 56.95 from Sundance Solar. This company was also the best in terms of service and quality delivered.
Some small stuff that can be found in stationary shops, needle work and hardware shops: Sctoch double sided tape #668 from 3M around 2cm wide, vinyl tape to cover the solder points, around 1m two wire cable (we used the multi stranded type around 1mm in diameter each to have a soft feeling) and Textile glue.
Before cutting a hole in your bag, a few words on our design: We wanted the solar panel integrated as seamless as possible, it should look as the bag was designed with a solar panel in mind. We decided to laminate the solar panel to the fabric of the bag, no stitches visible.
We begin by marking the bag where the hole of the size of the active area of the solar panel will be (you will see easily what we mean with the active area when you have the solar panel in front of you) and cut the hole out (see images 1 to 3).
Prepare the solar panel by soldering the cable to it (see image 4). write down which cable (color) you connect to the plus terminal and the minus terminal. Which is plus and minus is shown in the data sheet that comes with the solar panel.
The solar panel has around 2cm of additional plastic area outside the active solar cells, this is the area we use for lamination. For reliable and strong lamination, clean this area very thoroughly with a soap solution or window cleaner.
Apply the double sided tape on the cleaned edges of the panel (see images 5 and 6) and rub them with your fingernail as hard as you can on to the solar panel (see image 7). Wrap a good share of vinyl tape around the solder points to insulate them and give support (see image 8).
The solar panel is now ready (see image 9) to laminate to the bag. But before you do this, decide how you will guide the power cable through your bag to a place where the electronic box the size of around 7cm x 5cm x 2cm will be.
Slide the solar panel through the hole into the bag and don’t forget to guide the power cable at the same time inside the bag (see images 12 and 13). Take off the protective paper of the double sided tape one by one and place the solar panel to match the hole you cut out earlier. Apply pressure to ensure the panel stays in place first. Then use a piece of cloth like linen and use again your fingernails to force the fabric on to the glue of the tape. The linen will avoid rub marks from you fingernail on the bags fabric (see image 11).
You are almost done. Check if the edges of the cutout around the solar panel are clean and no loose treats are there. Cut them off if needed. Apply textile glue around the edge of the solar panel cutout. The textile glue is used for seaming the edges of the fabric and can withstands wear, tear and washing - perfect for our design.
You can now reward yourself with a good cup of tee or coffee. Next time we show you how to make the electronic part which is much easier than modifying the bag.