New Energy Solutions
What Are Polycrystalline Solar Panels?
There are a few main kinds of solar panels on the market today, monocrystalline (or mono) panels, polycrystalline and thin film solar panels. They each have their own strengths and weaknesses and which one you decide to go with is usually dependent on what you wish to achieve through solar power as well as your budget and installation requirements.
Polycrystalline solar modules are a great choice for many, they’re an efficient and powerful panel that is often more affordable than their sister monocrystalline PV modules. This is largely due to differences in their manufacturing process and the kind of silicon used. Here we’ll outline what exactly polycrystalline solar panels are, how they’re made and the benefits of installing them.
Key Takeaways:
What They Are: Polycrystalline solar panels are made from multiple silicon crystals in each cell, unlike monocrystalline panels, which use a single crystal per cell. This difference makes them more affordable.
Manufacturing Process: The panels are made by melting silicon crystals into a mold, cutting them into thin layers, and then treating them with chemicals to improve efficiency, including texturing, diffusing, and coating.
Cost-Effective Option: Due to their simpler manufacturing process, polycrystalline panels are generally cheaper than monocrystalline ones, which require more complex methods and expensive equipment.
How to Spot Them: Polycrystalline solar cells have square corners, while monocrystalline cells have slightly rounded or chopped-off corners.
What are Polycrystalline Solar Panels?
Polycrystalline, sometimes referred to as multicrystalline PV modules, or solar panels get their name from the type of silicon used in their manufacturing process. These panels are made from polycrystalline solar cells, this basically means each cell is made up of multiple silicon crystals as opposed to monocrystalline panels where each solar cell is made up of only one singular silicon crystal.
How to Identify Polycrystalline Panels:
The main and easiest way to decipher between a mono and a polycrystalline panel is in the shape of the solar cells, where in a monocrystalline panel the corners of each solar cell are slightly rounded or chopped off, in a polycrystalline solar cell the corners a completely square.
How are Polycrystalline Solar Panels Made?
Polycrystalline solar panels are widely regarded as being more affordable than monocrystalline alternatives. This comes down to the manufacturing process and materials used in making the individual solar cells. The process for manufacturing a polycrystalline panel is far more simple:
Melt Silicon
The first step in this process is to melt a number of silicon crystals together to create a molten liquid, this liquid is then poured into a box shaped mould where it is let to solidify creating a large almost brick shaped silicon block.
Silicon Blocks are then Cut to Shape
These silicon blocks are then sliced into thin layers, creating the solar cell as you’ll see it in your panels. This isn't the final step in the solar cell manufacturing process, for these cells to produce electricity they need to undergo further processing and treatments.
Steps for Solar Cell Manufacturing:
STEP 1: Texturing
The surface of the silicon wafer is then etched with a number of chemicals, this is done to remove a thin layer on the surface of the silicon, almost roughing up the surface in a sense allowing for more surface area and as such more generation.
STEP 2: Diffusing
The surface of the silicon is then diffused with phosphorus creating a negative charge in the front face and a positive charge on the back face.
STEP 3: Coating
Now the silicon is almost a functioning solar cell the surface is then coated in silicon nitrate, this is done to reduce the reflective properties and maximise the amount of light absorbed.
STEP 4: Printing
Metal conducting strips are then printed onto the surface, these strips will collect the electricity produced by the cells.
Polycrystalline vs. Monocrystalline Solar Cells:
The process for manufacturing polycrystalline solar cells is far more and less expensive than mono solar cells. Monocrystalline solar cells require that each individual cell is made from a singular ingot of silicon. These ingots are grown in a crystal growth machine, this process can take days or weeks even and costs millions to set up, making mono panels more expensive than polycrystalline.
To Sum It All Up...
Now we've covered what exactly polycrystalline solar panels are, how they work and the main differences between them and other options on the market, you can go off and make an informed decision around solar and the type of system that's best suited to you.
FAQ
Frequently Asked Questions about Installing Solar Power
There are great government rebates/incentives still in place for eligible households. Basically, the larger the panel array, the more STCs your solar system generates as it is based on the expected output of the system over time.
When you buy a solar system, the purchase price is normally reduced by the value of the STCs created by your system. You simply fill out a form on the day of installation to confirm that the system has been installed, and that’s it. There is no additional paperwork that you need to do.
Small-scale Technology Certificates (STCs)
Small-scale Technology Certificates (STC’s) – previously known as Renewable Energy Certificates or RECS – are created when a Renewable Energy System such as a Solar PV system is installed.
The number of STC’s depends on the predicted amount of energy generated and hence the larger the system the greater the rebate. In essence, one STC is created for every megawatt-hour of production capacity of the system.
This is further multiplied by the number of years the system is likely to generate energy (for home solar systems, this is usually 15 years, although the life of the solar panels themselves is considerably more than that).
This incentive program is being phased out until 2030, so each year the number of certificates your system is eligible for reduces.
STC Price
The system for trading and pricing STCs for small systems is managed by the Small-scale Renewable Energy Scheme (SRES).
STCs are bought by Liable Parties (usually electricity retailers) and must be surrendered at the end of each quarter. As the number of STCs that are required to be surrendered is a fixed amount each year, but the number of STCs created is variable, the price paid for STCs also varies and is determined by supply and demand.
The Federal Government legislated in 2010 a fixed price for STCs by implementing a Clearing House system where STCs can be bought and sold for $40. However, there is no requirement for Liable Parties to purchase from the Clearing House, so they are likely to only do so if there is a shortage of STCs or the market price exceeds $40. There is currently a surplus of STCs in the market which means the market price of STC’s below $40
The Feed In Tariff is only something you need to worry about if you don’t have battery storage.
The price your chosen energy retailer pays for any excess electricity generated from your solar panels is recorded as a credit on your power bill.
In NSW, solar power is fed into your home as it is generated and your household will use it first before you draw power from the grid.
This means that for every kWh of solar power used in the home you are directly saving money you’d spend on your power bill. This reduction in your power bill is the main financial benefit of solar power.
Everything else will be bought up at an agreed rate by your electricity retailer.
At the moment, most feed-in tariffs are between 5 and 10 cents per kWh, with many being about 7 cents. They bounce up and down a lot, for example in previous years they have been up over 20 cents per kWh. Typically, they are always at least 5 cents per kWh.
Once you sign up for a 1KOMMA5° Installation, we immediately submit your grid application to the relevant energy distributor. For systems up to 5kWs, this is a formality. For larger systems it can take a few days or more. Once we receive approval, your installation will be managed by our installation coordinator, who will welcome you to 1KOMMA5° and book an installation date for you. This is generally booked within around two weeks and installation dates are available Monday to Friday, weather permitting.
We endeavour to have your system installed within 2-4 weeks unless you request us to hold for whatever reason. Due to our strict safety policy, we do not install solar systems when it rains. In the event of inclement weather, we will rebook your installation as soon as possible. We always work with your requests as we strongly recommend that someone be home on the day of installation.
Green Loans can be an affordable way to pay for your solar power system and is only available for approved products. As a Clean Energy Council Accredited installer, all our systems qualify.
Green Loans can be used to finance 1KOMMA5° systems from $1,000 to $30,000 over a 2-7 year term. Once you have received a referral from 1KOMMA5°, online approval usually occurs within 1-2 business days. Green Loans have a competitive fixed interest rate that is as low as 7.99% p.a.* | Comparison rate 9.21% p.a.^ Establishment fee of $299 added to the loan amount. $2.70 per week account keeping fee included in repayments.
To be eligible to apply you must:
Be over 18 years old and an Australian resident or citizen
Own or be purchasing a home
Be employed, self-employed, a self-funded retiree; or is receiving the Government Age Pension
Have an Australian driver’s license or Passport
Provide two most recent payslips or 90 days of bank statements
There are a number of good, competitive Green Loan providers – ask us about the options available.
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