Almost every solar panel sold in Georgia today is monocrystalline silicon, but there are real differences between cell technologies, between monofacial and bifacial panels, and between glass-backsheet and glass-glass construction. In Georgia's climate, with hot summers in the east, snow in the highlands and hail in Kakheti, those differences change both output and risk. This guide explains the main types and which ones suit which project. Information is as of October 2026.
Solar panel types at a glance
| Type | What it is | Typical module efficiency | Temperature coefficient (Pmax) | Where it fits |
|---|---|---|---|---|
| Mono PERC (p-type) | The standard of the last decade; manufacturers are phasing it out | about 20–21.5% | about −0.34 to −0.35% per °C | Budget rooftop systems |
| TOPCon (n-type) | Today's mainstream cell technology | about 21.5–23% | about −0.29 to −0.30% per °C | Most rooftop and ground projects |
| Heterojunction, HJT (n-type) | Premium cells with low heat losses | about 22–23.5% | about −0.24 to −0.26% per °C | Hot sites, limited roof space |
| Back-contact (n-type) | Contacts on the rear, no front busbars | about 22.5–24% | about −0.26 to −0.29% per °C | Premium rooftops |
| Polycrystalline | Older, less efficient technology | about 16–18% | about −0.40% per °C | Not recommended for new projects |
Figures are typical ranges from 2025–2026 manufacturer datasheets; always check the datasheet of the exact model.
What the temperature coefficient means. Panels lose power as they heat up. On a summer afternoon in Tbilisi or Kakheti, cells can run 30–40 °C above their 25 °C test temperature. A panel with a −0.30% coefficient then loses about 1.5 percentage points less output than one with −0.35%, which adds up over a hot season.
Monofacial or bifacial?
Bifacial panels collect light on both sides. The rear side typically produces 70–90% of the front side's output per unit of light (the "bifaciality factor": about 70% for PERC, about 80% for TOPCon, about 85–90% for HJT). The extra yield depends on the ground under the panels:
- on grass or soil, a gain of roughly 5–10%;
- on light gravel, concrete or snow, more;
- on a flat roof close to the surface, little or none.
For ground-mounted plants in Georgia, bifacial TOPCon is now the default choice. For pitched house roofs, where the back of the panel faces the roof, monofacial panels are simpler and usually cheaper.
Glass-backsheet or glass-glass?
- Glass-backsheet: glass at the front, a polymer sheet at the back. Lighter and cheaper; standard for most rooftops.
- Glass-glass: glass on both sides (needed for bifacial). More rigid, better against moisture and micro-cracks, and usually comes with longer warranties (often 30 years of performance).
What matters in Georgia's climate
| Condition | Where | What to choose |
|---|---|---|
| Strong sun, about 1,250–1,350 kWh per kWp a year | Central and eastern Georgia: Shida Kartli, Kvemo Kartli, Kakheti, Tbilisi | Higher-efficiency n-type panels; size the inverter for summer peaks (PVGIS) |
| Hot summers | Kakheti, Tbilisi, Kvemo Kartli | A low temperature coefficient (TOPCon or HJT) and good rear ventilation |
| Snow and altitude | Javakheti plateau, mountain regions | Panels rated for high snow loads (5,400 Pa front load is common), steeper tilt, more ground clearance; bifacial gains from snow |
| Hail | Kakheti, where the state runs an anti-hail system (source) | Panels hail-tested beyond the standard, thicker or tempered front glass, glass-glass, and insurance that covers hail |
| Lower irradiation and humidity | Western Georgia (about 1,100–1,200 kWh per kWp) | Panels with good low-light performance; strong frames and sealing against humidity |
See our PVGIS yield map of 16 Georgian locations for site-by-site output.
Certifications and warranties to check
- IEC 61215 and IEC 61730. The international standards for module performance and safety. Every serious supplier's datasheet lists them.
- Bankable manufacturer. Lenders prefer manufacturers on recognised bankability lists, with audited financials and a track record. See what lenders ask for.
- Product warranty of 12–25 years and a performance warranty of 25–30 years, with a stated first-year and annual degradation (n-type panels are typically about 1% in year one and about 0.4% a year after that).
- Independent test reports for PID, light-induced degradation and hail where available.
- A local distributor that can handle warranty claims in Georgia.
Which panel for which project
- House roof: monofacial TOPCon, 430–460 W in a compact format, black frame if appearance matters. See prices and payback.
- Commercial flat roof: monofacial TOPCon of 550–620 W on a ballasted or anchored frame, checked against roof load.
- Ground-mounted plant (500 kW and up): bifacial TOPCon glass-glass, 580–640 W, on fixed structures with enough clearance, or on trackers for larger plants. See our solar farm development guide.
- Buying an operating plant: check the module model, its datasheet, the warranty terms and how much degradation the monitoring data shows. See our due diligence checklist for buying a solar plant.
Frequently asked questions
Which solar panels are best for Georgia? For most new projects, n-type monocrystalline panels (TOPCon, or HJT where heat is a concern). Bifacial glass-glass versions are best for ground-mounted plants; monofacial panels suit pitched house roofs.
Are bifacial panels worth it? On the ground, usually yes: the 5–10% extra yield on grass or soil costs little extra. On a pitched roof the rear side gets almost no light, so the benefit is small.
What is the difference between monocrystalline and polycrystalline panels? Monocrystalline cells are cut from a single silicon crystal and are more efficient. Polycrystalline panels are an older, less efficient technology and are rarely used in new projects.
Do solar panels work in winter and snow? Yes. Cold improves panel efficiency, and snow slides off steeply tilted panels. Output is lower in winter because the days are shorter and the sun is lower.
Choosing modules for a plant or reviewing an EPC offer? See our solar advisory services or contact us.
