Guide
Solar panel types: monocrystalline, polycrystalline, thin-film, bifacial
In a quote the panel often takes a single line: brand, model, wattage. Yet the technology affects how much power fits on the roof, output on hot days and long-term yield. This guide explains the common solar panel types and how to choose.
Short answer
In rooftop solar energy systems today the most common choice is monocrystalline panels, which fit more power into the same area. Polycrystalline panels appear less and less in new projects. Thin-film panels serve some special uses. Bifacial panels also produce from light reflected onto their rear side and add yield when mounted well. The right choice depends on area, shade, heat, roof load capacity and warranty terms.
This guide was prepared by the Ufkon editorial team and reviewed on 19 Oct 2026. It is for information only and does not replace legal, financial or technical advice.
Four main solar panel types
Monocrystalline panels
Cells are cut from a single silicon crystal and usually look dark and even. Power per area is high, so they stand out when roof space is limited. Terms such as PERC, TOPCon and heterojunction (HJT) describe different cell technologies within this family.
Polycrystalline panels
Cells are made of several silicon crystals and look blue and grainy. Efficiency per area is lower than monocrystalline. They are offered less often in new projects; if a bid uses them, check the area and yield figures closely.
Thin-film panels
A very thin semiconductor layer is applied to glass or a flexible surface. Light and flexible options exist and they are usually less affected by heat. Lower efficiency per area means more space is needed for the same power.
Bifacial panels
The rear side is also light-sensitive and adds output from light reflected by the ground or roof. The gain depends on surface colour and mounting height. It can pay off on light-coloured flat roofs with tilted frames; flush mounting close to the roof limits it.
Solar panel types compared
The table shows general trends. Models within the same type differ too; the datasheet gives the exact values.
| Type | Strength | Watch for | Good fit |
|---|---|---|---|
| Monocrystalline | High power per area | Differences between models and cell types | Most home, business and factory roofs |
| Polycrystalline | Widely known technology | More area for the same power | Projects where space is not tight |
| Thin-film | Light and flexible options | Low efficiency per area | Low load capacity or special surfaces |
| Bifacial | Extra output from the rear | Gain depends on mounting and surface | Light flat roofs, tilted frames, ground mount |
What to check when choosing a panel
- Power (Wp) and efficiency: they set the total power that fits on the roof; efficiency matters most when space is short.
- Temperature coefficient: output falls as the panel heats up; a lower value means smaller losses on hot days. It is on the datasheet.
- Product warranty: covers manufacturing defects; have its length and scope written separately.
- Performance warranty: a commitment that the panel keeps a set power level over the years. Check the annual degradation curve and who gives it.
- Tests and certificates: ask for conformity with international test standards such as IEC 61215 and IEC 61730.
- Weight and size: they affect roof load and layout and feed the structural check on large roofs.
- Glass-glass or glass-backsheet build: it changes durability, weight and bifacial use.
How shade, heat and layout affect the choice
Where and how a panel is placed matters as much as its type. On a partly shaded roof even a high-efficiency panel may miss the expected yield; half-cut cell designs and panel-level electronics can reduce the loss.
In hot regions panel temperature rises in summer and output drops, so the temperature coefficient is a key point when comparing bids. Mounting that lets air flow behind the panels also limits heating.
What does "Tier 1 panel" mean?
Tier 1 appears often in quotes. It is not a quality certificate; it is a ranking based on the maker's financial scale and bankability for large projects. On its own it does not show that a panel suits your roof. Ask for the datasheet, the warranty document and who honours the warranty locally.
How a quote should describe the panel
Instead of phrases like "high-efficiency panel", ask for brand, model, quantity, unit power (Wp) and the datasheet. When bids propose different panels, compare total power and estimated annual yield on the same assumptions. Choose panels together with the inverter; shade and orientation affect both.
In a renewable energy investment the panel is only one cost item. See solar panel cost for the others and the 12-point comparison guide to compare bids line by line.
Ufkon does not sell panels and never installs. When you create a project request interested approved firms unlock it and message you; if you wish, bids arrive in the same template side by side. See how it works.
Frequently asked questions
Which solar panel type suits a home roof?
Space is usually limited on homes, so monocrystalline panels stand out. Roof area, shade and budget decide; solar panels for homes is a good start.
Do bifacial panels produce more on every roof?
No. The rear gain needs a reflective surface and enough height above it. Flush mounting close to the roof limits the gain; ask the firm how it was calculated.
Is a higher wattage panel better?
Not on its own. Higher wattage panels are usually larger. What matters is total power on the roof, the temperature coefficient, the warranty and the design of the whole system.
How long do solar panels last?
Panels are built to run for many years and makers back this with a performance warranty. The term and annual degradation vary by model; read them on the datasheet and warranty document.
How do I compare bids with different panels?
Put total power, estimated annual yield and warranty terms side by side, then check cost per kWp. Details are in the quote comparison guide.
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