Published on August 17th, 2015 | by Glenn Meyers
DIY Solar Panel Tips: Build Your Own
If you’re ready for the low-down on a DIY solar panel, read on.
Nearly all sustainability geeks would like their house, garage, greenhouse, and business to be plastered full of solar panels. Unfortunately, there is the hard-edged reality of affordability. Installing solar panels on any structure is a high-cost proposition, now matter how good the ROI may look years down the road.
Okay, don’t get stopped in your tracks because you can’t have all of those solar panels you’d like to help remove you escape grid dependency. If you’re handy, and experienced in building, you can just build one solar panel, and see where you can go from there. Then tweak it, and build more when you can.
Armed with this trove of information, you can join the ranks of Edison, Tesla, and Einstein, taking your inaugural shot at creating green electricity.
Think of the project this way: Solar cells (your basic materials) continue to get less expensive. Solar panel DIY builder Ovidiu Sandru says, “While you could pay up to $10,000 for an off-the-shelf installation and could cover the system’s price in just over 10 years, it’s still better and more educational to make one yourself.”
So if you’re ready for this green venture, let’s get started.
Tools & Materials you will need
- Soldering iron & solder
- Solder paste
- Flux (for removing the grease off the wires)
- Some wooden board
- Protective glasses
- Multimeter to measure voltage and amperage
- Sharp pencil
- Tape measure
- Framing square
- Solar cells
You can get cheap solar cells from places like Amazon , eBay , or Sun Electronics, to name just a few options on this list of PV resources. Your search should also show there are numerous solar cell types to choose from. These include Chinese, Japanese, and American brands. American ones are usually the most expensive, but they also come with guarantees.
There are a few different types of solar cells to buy, but the best cost-to-efficiency option will be polycrystalline cells. Buy however many you need for producing how much energy/wattage you want. The specs should be listed when you purchase the cells.
If you’re leery about starting from scratch, you can also buy a kit to build a panel. Kits like the Sunnydaze solar pump and solar panel kit provide decent options for launchin this sustainable energy venture.
Plan your solar panel system with care and make certain everything you build is square. Make all measurements as precise as possible. You do not want to make mistakes that need correcting after the solar panel has been built. Remember, it is far easier to erase and redraw early errors that than it is to undo soldered joints or wiring systems.
Size of your solar panel
According to howstuffworks, building solar panels that will provide enough electricity for an entire home is a large proposition.
A “typical home” in America can use either electricity or gas to provide heat — heat for the house, the hot water, the clothes dryer and the stove/oven. If you were to power a house with solar electricity, you would certainly use gas appliances because solar electricity is so expensive. This means that what you would be powering with solar electricity are things like the refrigerator, the lights, the computer, the TV, stereo equipment, motors in things like furnace fans and the washer, etc. Let’s say that all of those things average out to 600 watts on average. Over the course of 24 hours, you need 600 watts * 24 hours = 14,400 watt-hours per day.
From our calculations and assumptions above, we know that a solar panel can generate 70 milliwatts per square inch * 5 hours = 350 milliwatt hours per day. Therefore you need about 41,000 square inches of solar panel for the house. That’s a solar panel that measures about 285 square feet (about 26 square meters). That would cost around $16,000 right now. Then, because the sun only shines part of the time, you would need to purchase a battery bank, an inverter, etc., and that often doubles the cost of the installation.
Wow! Maybe small is the most logical place to get started.
Layout your panel
According to FreeSunPower, a typical 12 volt panel about 25 inches by 54 inches will contain 36 cells wired in series to produce about 17 volts peak output. Using this size, place your square solar cells onto a plywood or laminated board and carefully draw all separating lines. The Sunnydaze kit also features 36 cells.
Here are some instructions to assist with your layout.
Wire the solar panel system
After planning the physical layout of your solar cells on your board, you are ready to begin soldering the wires, first to the solar cells, and then to each other.
Start by linking the cells in series. Remember this electrical basic rule: the positive lead is soldered to the negative lead of the next cell. Do this for as many cells as needed to reach a voltage of 12 or 24 volts. Do not exceed that as you would enter the area of dangerous voltages. You want to generate serious power here, not fool around and you don’t want to electrocute yourself. The power remains the same, after all. You just need a minimum of 12 volts to kick-start a 12V inverter for generating 110/220V AC or charge your 12V battery packs. Linking your cells in series will increase the voltage.
Following this, glue the cells to the board using a water-resistant adhesive. It is better if you made them a frame where they can be inserted individually, so you can replace defective ones. Before you’ll have stuck all the cells in the right place, make sure you have drilled holes for your wires. Make connection buses (in computing, a bus is a set of physical connections (cables, printed circuits, etc.) which can be shared by multiple hardware components in order to communicate with one another) along the positive and the negative lead and then connect those buses (thicker wires) in parallel (plus to plus, minus to minus) to have a parallel connection and increase the amperage.
Test your work
Take your panel out in the sun to see what it’s generating. You first have to measure the voltage, and then the short-circuit amperage. Just make sure your ammeter bears the solar cells’ nominal power (108W at 12V means 9 amps).
You can now power anything that runs on DC current, charge your car battery and so on. If you succeeded doing these 5 steps, then you can order some more solar cells until you reach the power you want for your system. Remember, the more power you want, the larger the inverter you’ll need to get.
Now you are ready to connect your sustainable power source!