You’ve probably heard about solar farms sprouting here and there in every country, with each country reporting to have cut down their dependence on fossil fuel for energy. You’ve probably heard about climate change being a reality but did you know that you can build a solar farm in your own backyard?
The sun is free, renewable and ever present, even if you see downcast skies covering the horizon. Sure, you can invest in several units of 12V solar panels but did you know you can create a working panel on your own?
Building your own 12V solar panel cuts down on costs and adds to your skill as an individual. You also cut down on installation expense as well as maintenance since you were the one who made it and would know where the problem lies.
To start your DIY 12V Solar Panels project, you would need the materials listed below. Except for solar cells, all of these can be bought from your local hardware or handyman shop.
- Solder paste
- Composite boards, plywood or ply boards measuring at least 28 inches x 58 inches
- Glue or any strong, heat-resistant adhesive
- Solar cells, you can buy these online. Polycrystalline is the most affordable option.
- A length of electrical wire, ideally this should be of the same size as the solar cell wiring
- A 12V car battery or a 12V battery made specifically for solar panel installations.
- Some nails, two-three inches, depending on the thickness of your backing board
- Electrical tape
- Soldering iron
- Protective glasses
- Tape Measure
- Multi-meter (for measuring electric current)
Compute for Sizing
This is an example of a real-life application of the mathematical principles we learned in high-school. It’s all about the numbers.
First off, set a baseline for the expected output. Generally, this should be the amount of energy, measured in kilowatt-hours (kWh), that you would need to power your household. Get your electric bill for the past three months and get the daily average consumption. (3 x z) / 90 = daily consumption in kWh.
Once you have this figure, estimate the total energy that the panels can produce. A square inch of solar cells can generate about 150-200 watts per square meter in good sunlight. Using the figures, you can use this formula to determine the size of your solar panel installation.
(Daily consumption in kWh / 5 solar hours) / Efficiency ratio of 20% / solar input rate of 1000
4 kWh * 1000 kWh = 4000 Wh
4000 Wh / 5 h = 800 W
800 W / 0.20 = 4000 W
4000W / 1000W per sq.m. = 4 sq.m.
Given the example, you would need about four square meters of solar panel if your daily requirement is 4kWh per day.
Building your solar panel:
Using the requirements above, this will cover a solar panel measuring 2mx2m but you can split this into four 1mx4m panels as well.
- Cut your backing board according to the size that you want but give it some allowance for good measure.
- Using a tape measure and pencil layout the solar cells on the backing board and create a gridlines but leave a little gap in between cells.
- Drill some holes into the backing board so the solar cell wires can pass through.
- Prepare to solder the wires of the solar panel. Create a series based on the gridlines you created, linking each unit with the next. The positive lead should be soldered to the negative lead and repeated until a voltage of either 12 or 24 volts is reached. These are the upper limits in a series.
- Once you reach the maximum voltage, affix the solar cells to the backing board using water-resistant adhesive.
- Build connection buses to increase the amp output. Connect the lead wire to an inverter which should be then connected to the battery.
- Once every wire has been soldered and taped neatly, prepare to do a quick test of the panel.
- Take the assembly out and set it under the sun for about two hours. Using the multi-meter, test if the battery is charging.
- If all goes well, connect all your panels into the inverter and battery and then relay it to the electrical main.
It may be intimidating at first but a little practice and you should be able to build solar panels faster, and your experience can provide more tips and tricks on how to do things better.