solar cell, or photovoltaic cell, is the basic building block of a solar panel which represents a small device that transforms solar radiation into electricity. These cells are most commonly made of silicon – a semiconductor material valued for its good photoconductivity and cost-efficiency.
What's the difference between monocrystalline and polycrystalline solar panels?
To manufacture a solar cell, purified silicon is melted and then cooled again to form crystallized ingots. These ingots are later cut into wafers that work as a substrate for the cells. Some ingots are made by a technique called the Czochralski process - a method to grow a single large crystal of silicon; the cells produced from such ingots are called monocrystalline, or mono Si cells. Polycrystalline or poly Si cells, on the other hand, are manufactured by melting many small crystalline grains together.
Monocrystalline solar panels: premium quality for a higher price
To make monocrystalline panels, high-purity silicon is used making them appear black in color. These panels are generally considered a premium product due to their higher efficiency: most options available on the market today convert from 15% to 24% of the light hitting them into electricity.
Another big advantage of mono Si panels is that they generate more energy per square foot than poly Si alternatives, meaning you’ll need fewer solar panels for the same energy output. These panels perform better at high temperatures and in low-light conditions, plus have a longer lifespan. Even though most monocrystalline solar manufacturers offer 25-year warranties, these panels can last up to 40 years.
The disadvantage is obviously the higher price: the US average cost to install a residential mono Si solar system ranges from $5,000 to $8,400.
Polycrystalline solar panels: more affordable but less efficient
As we found out above, polycrystalline solar cells are manufactured using multiple silicon grains. The light reflected from the grain boundaries gives these cells a shimmering appearance that is perceived by the human eye as a navy blue color.
Poly Si panels have a lower efficiency rating of between 13% and 20%, and hence require more space to achieve the same output as monocrystalline panels. They are also less heat-tolerant and perform worse with low or diffused light. Most poly Si solar panels come with a 25-year warranty but can last up to 35 years.
The most significant benefit of polycrystalline panels is higher affordability: a residential solar system with poly Si panels typically costs between $3,000 and $6,000. Polycrystalline solar panels also have an edge over mono Si solutions when it comes to eco-friendliness, as their manufacturing produces less waste.
Monocrystalline or polycrystalline solar panels: Efficiency vs affordability. Monocrystalline for higher efficiency; polycrystalline for cost-effectiveness.
Bottom line: choose mono Si to get the best efficiency and poly Si to spend less on the solar purchase
Before deciding on a solar panel type and going ahead with the purchase, you should get clear on your priorities. Monocrystalline solar panels are a solid choice for homeowners who focus on getting the most efficient solar solution available on the market, while polycrystalline panels offer a compelling alternative for those on a tighter budget.