Glossary
Monocrystalline panel
A monocrystalline panel is a solar panel made from cells cut from a single silicon crystal, which gives it higher efficiency per area and a uniform black appearance. It is the current standard in residential installations; polycrystalline panels (bluish, less efficient) are almost never installed on new homes anymore.
What a monocrystalline panel is
A solar cell is a silicon wafer. When that wafer comes from a single crystal, electrons move with fewer obstacles and the cell converts more light into electricity. That is the monocrystalline panel. Polycrystalline was made by melting silicon fragments together; it was cheaper and less efficient, and has nearly vanished from the residential market.
Within monocrystalline there are variants (PERC, TOPCon, HJT, bifacial) that improve efficiency or heat performance. For a homeowner, the practical difference among them is smaller than the difference between a serious manufacturer and one that is not.
Why it matters in Florida
Two things weigh in Florida: heat and space. Panels lose some output as cell temperature rises, and here it rises a lot. The spec sheet number to look at is the temperature coefficient: the closer to zero, the better it behaves in summer. And since many roofs have small or poorly oriented slopes, efficiency per square foot determines how many kW fit in the good space.
Degradation also matters: how much the panel loses each year. It is stated in the manufacturer’s production warranty and varies by brand.
Common mistake
Choosing a proposal for the panel’s “premium brand.” In a residential system, the panel is a fraction of the cost and rarely the source of problems; the inverter, the workmanship and the installer are. Ask for the spec sheet, compare temperature coefficient, product warranty and production warranty, then spend more attention on who installs it. Types and warranties are compared in solar panel types and warranties.
Full guide: Solar panel types and warranties: what to buy and what to ignore →
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