Introduction
I have been interested in solar power for my home for a long time. I want to save money on my electricity bill and be more self-sufficient. The problem is that buying and installing a full solar system from a company costs tens of thousands of dollars. I wondered if I could build my own solar panel system and save a lot of money. After doing a lot of research, I found out that building DIY solar panels is totally doable for a fraction of the cost of commercial systems.
In this article, I'll walk you through everything I learned about designing and building DIY solar panels and setting up a complete solar power system for your home. The utility companies don't want you to know that this is possible. But with a little bit of knowledge and some simple materials, you can harvest free energy from the sun to power your home appliances and slash your electric bill.
How Solar Panels Work
Before we get into the DIY solar panel build, let's review the basics of how solar photovoltaic (PV) panels work. Understanding the underlying technology will help as we design and build our system.
Solar panels are made up of many individual solar cells wired together. Each solar cell is made of layers of semiconductor material, usually silicon. When sunlight hits the solar cell, the energy knocks electrons loose, allowing them to flow and produce DC electric current.
The solar cells are encased between a clear top covering and a protective backing. When sunlight penetrates the top layer, it creates an electric field across the semiconductor layers causing electricity to flow. The more intense the sunlight, the more electricity is produced.
Multiple solar cells wired in series increase the voltage. Connecting the cells in parallel increases the current. A typical 12V solar panel may have 36 individual cells wired together to produce enough power to charge a 12V battery.
DIY Solar Panel Options
There are a several methods for building DIY solar panels. The main options include:
Buy Individual Solar Cells
You can buy individual solar cells and wire them together yourself. This gives you total control over the solar panel design. But purchasing large quantities of cells can get expensive.
Solar Cell Kits
Another option is to buy a solar panel kit that includes solar cells and busbars for connecting them together. The kit provides everything you need except the outer casing.
Build From Scratch
Some ambitious DIYers build panels completely from scratch by forming their own silicon semiconductor wafers. This requires advanced skills and knowledge but yields high quality panels.
For my first solar project, I decided to go with a solar panel kit. This allowed me to assemble my own panels without complex solar cell fabrication.
Calculate Your Solar Panel Needs
Before purchasing solar cells and components, it's important to calculate how many panels you will need. The number and wattage of solar panels will depend on:
- Your average daily electricity usage
- Hours of full sunlight in your location
- Space available for mounting panels
I took a look at my past electric bills to get an average of my daily kilowatt hours (kWh) used per day. This told me how much power I would need to produce with my solar panels.
Next I researched the solar insolation, or sun hours per day, for my area. This gives the amount of peak sunlight I can expect on average.
I multiplied my average kWh per day by 1.3 to allow for some cloudy days. Then I divided this by my location's sun hours to get the total wattage of solar panels needed.
For example, if I use 30 kWh per day multiplied by 1.3 equals 39 kWh. And my location has 5 sun hours per day. So I would need about 39 / 5 = 7,800 Watts of total solar panel capacity.
Select a DIY Solar Panel Kit
With my solar panel wattage calculated, I could start pricing out kits. I researched different manufacturers and compared reviews and specs.
Some of the factors I considered in choosing a solar panel kit included:
- Cell efficiency - higher is better but more expensive
- Cell size - impacts wattage output
- Number of cells - more cells can produce more watts
- Price per watt - lower cost for more value
Based on my research, I selected a 156mm x 156mm monocrystalline cell kit with 60 cells rated at 5 watts each, so 300 watts total capacity per panel. This gave me a good balance of efficiency, power output, and cost.
The kit included the silicon cells, connecting busbars, and materials for six panels at a price of $0.45 per watt. So purchasing enough kits to meet my 7,800 watt goal would cost around $3,500.
Assemble the DIY Solar Panels
With my kits purchased, I was ready to begin assembling my DIY solar panels! I carefully laid out the components for each panel:
- 60 solar cells
- Busbars
- Flux pen and solder
- Epoxy resin
- Aluminum backing
- Transparent glass covering
Step 1 - Solder the Solar Cells
I started by using the flux pen on each cell to prep the surface for soldering. Next I gently soldered the busbars in place to connect all the cells together in series. I repeated this panel by panel until all cells were wired up.
Step 2 - Laminate the Panels
With the cells soldered, I mixed up a batch of clear epoxy resin to encapsulate and seal the cells. I carefully poured the resin over each panel and used a squeegee to spread it evenly. The resin hardened to form a tough, protective top layer.
Step 3 - Add Backing
Once the epoxy resin dried, I cut pieces of aluminum sheeting to size and glued them to the backs of the panels as a moisture barrier.
Step 4 - Wire Outputs
For the final step, I soldered cables to the positive and negative output contacts on each panel to deliver the electricity.
In a few hours I had successfully built six high quality 300 watt solar panels for a fraction of commercial prices. Now it was time to install them!
Set Up the Complete Solar Power System
With my homemade solar panels ready, it was time to install the full DIY solar system to start generating power.
Mount the Solar Panels
I installed a ground mount racking system and strategically placed the panels for optimal sunlight. Proper orientation and tilt angle helps maximize energy production.
Connect Batteries and Inverter
The panels output 12V DC current. So I wired the panels into 12V deep cycle batteries to store the energy. For household 120V AC power, I connected a power inverter to the battery bank to convert to alternating current.
Add a Charge Controller
Charge controllers regulate the voltage and current coming from the solar panels to safely charge the batteries. This protects the batteries from damage.
Wire to Electrical Panel
Finally, I wired the inverter directly to my home's electrical panel to power the household circuits. Now my solar electricity seamlessly powers lights, appliances, and other needs.
With the solar DIY project complete, I am generating 7800 watts of clean, renewable electricity to slash my electric bills! The entire project cost me around $3,500 compared to $20,000 or more for a commercial install. The utility company is losing out, but my wallet thanks me.
Enjoy Energy Independence with DIY Solar
Installing your own solar panel system takes some work, but pays off with free power generation for decades. You can build solar panels cheaply with a kit and basic components. With a ground or roof mounting system, batteries, inverter and charge controller, you can power your entire house independently.
DIY solar takes you off the grid and opens up energy independence. You can save money every month while also reducing your environmental impact. Once your system is set up, you simply sit back and soak up the free abundant sunshine while your home is powered renewably.
I am thrilled with how well my homemade solar panels are working. This project has shown me that anyone can break free of utility bills and start harnessing clean, renewable energy to meet their needs. I encourage you to explore how DIY solar panels can work for your home!