Monocrystalline Solar Panels vs Polycrystalline Solar Panels

Over six decades ago, New Jersey scientists announced their invention of a practical silicon solar panel. Solar panels have come a long way since then, but many are still made out of the same material: monocrystalline silicon. Monocrystalline solar panels remained the number one seller in the industry for many decades, yet that's no longer the case. In recent years, polycrystalline silicon solar panels have surpassed monocrystalline to become the highest selling type of solar panel for residential projects. Consumers who are now forced to pick between monocrystalline or polycrystalline are often left wondering, what’s the real difference?

How is Monocrystalline Made?

Both are made of silicon, of course, but producing monocrystalline is a much more involved process. Monocrystalline is made using the Czochralski process, named after the Polish scientist who serendipitously discovered it after accidentally dipping his pen into molten tin instead of ink. The process consists of rotating a solid silicon seed crystal while slowly extracting it from a pool of molten silicon. This process creates a pure block of silicon made of just one crystal (thus the name monocrystalline). This block, or ingot, is then cut into a square, creating a good deal of wasted silicon. The square of silicon is then sliced into uniformly colored wafers and assembled into the characteristic monocrystalline solar panel pattern. serendipitous

How is Polycrystalline Made?

In comparison, producing polycrystalline is relatively simple. A single silicon crystal seed and molten silicon are put into a square mold and allowed to set. The silicon cools at different rates as the outside cools more quickly and thus sets first. The uneven setting results in the creation of many different crystals (hence the name polycrystalline) giving the panel its sparkly, multicolored appearance.