--- title: "GCL GCL-NH12/66GDF-720 720W Solar Panel - Specs & Review | ComparePV" description: "GCL GCL-NH12/66GDF-720 720W solar panel. Specs: 23.20% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/gcl-gcl-nh12-66gdf-720" updated: 2026-09-11 --- # GCL GCL-NH12/66GDF-720 Solid all-round for its segment 222 panels in the segment HJT 700-750 W ## Identity - **Manufacturer:** GCL - **Model:** GCL-NH12/66GDF-720 - **Series:** GCL-NH12/66GDF - **Rated power:** 720 W - **Cell technology:** HJT - **Bifacial:** yes ## How it compares Compared against segment HJT 700-750 W (222 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 720 W | 715 W | Typical | | | Module efficiency | 23.20% | 23.02% | Typical | 1,306 | | Power density | 231.8 | 230.2 | Typical | 1,347 | | Temperature coefficient | -0.240 | -0.240 | Typical | 13 | | Weight (kg) | 37.9 kg | 38.3 kg | Typical | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 23.20% | 23.02% | Typical | 1,306 | | Power density | 231.8 | 230.2 | Typical | 1,347 | | Temperature coefficient | -0.240 | -0.240 | Typical | 13 | | Weight per kWp | 52.6 | 53.6 | Typical | 6,266 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | - **Best for:** Utility-scale and commercial. ## Specification ### Electrical - **Rated power (Pmax):** 720 W - **Efficiency:** 23.20 % - **Voltage at Pmax (Vmp):** 42.70 V - **Current at Pmax (Imp):** 16.87 A - **Open-circuit voltage (Voc):** 50.60 V - **Short-circuit current (Isc):** 17.67 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.240 %/degC - **Temperature coefficient of Voc:** -0.240 %/degC - **Temperature coefficient of Isc:** 0.040 %/degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** HJT - **Cell count:** 132 - **Bifacial:** yes ### Physical - **Length:** 2384 mm - **Width:** 1303 mm - **Thickness:** 33 mm - **Weight:** 37.9 kg - **Area:** 3.11 m2 - **Power density:** 231.8 Wp/m2 ### Warranty and degradation - **Product warranty:** 15 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 88.3 % - **First-year degradation:** 1.00 % - **Annual degradation:** 0.37 % - **Output after 30 years:** 636 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 1306 of 14005 | | Power density | 1347 of 14005 | | Temperature coefficient | 13 of 14005 | | Weight | 6266 of 14005 | | Warranty | 21 of 14005 | ## Pros - **Lowest Temperature Coefficient in Its Class** - HJT technology delivers a Pmax temperature coefficient of -0.24%/°C, significantly better than typical TOPCon modules (-0.29 to -0.32%/°C). At a cell operating temperature of 65°C, this translates to approximately 2–2.5% higher energy yield compared to competing TOPCon modules in the same power class. - **30-Year Power Warranty ≥88.27%** - The manufacturer guarantees ≥88.27% of nominal power output after 30 years of operation. This represents a meaningful advantage over the current market standard for TOPCon modules (~87.4% at 30 years) and especially over legacy PERC models (84.8% at 25 years), directly reducing LCOE for utility-scale PV projects. - **High Bifacial Factor of HJT Technology** - HJT cells achieve a bifaciality factor of typically 80–85%, well above TOPCon modules (70–75%). For installations on high-reflectance surfaces (albedo ≥0.3), this translates to a real annual energy gain of 8–15% above the front-side nominal output, at no additional cost. - **Efficiency Up to 23.2% — Top of Peer Group** - The top variant of the series (720 Wp) achieves 23.2% efficiency, matching the DMEGC DMxxxG12T-B66HSW and exceeding the Gamko New Energy GKA210N132 and Renesola RS9-700~720NBG-E1 (both at 23.18%) by 0.02 percentage points. The series therefore ranks among the absolute leaders in the 720 Wp segment. - **GCL Tier 1 BNEF — Bankable Manufacturer** - GCL-SI is consistently ranked as a Tier 1 manufacturer by BloombergNEF (Q1 2026 list confirmed), enabling non-recourse project financing through commercial banks and significantly reducing due diligence risk for industrial and utility-scale PV developers. ## Cons - **Weight of 37.9 kg — Installation Requirements** - The dual-glass construction increases module weight to 37.9 kg, compared to approximately 28–32 kg for backsheet modules of similar power output. This requires a two-person installation crew or specialized lifting equipment, which may increase Balance of System (BoS) costs by 5–10% per module in rooftop installation segments. ## About this series The GCL-NH12/66GDF series utilizes advanced **n-type TOPCon cell** technology, which effectively eliminates the problem of light-induced degradation, translating into stable energy production for decades. Thanks to the **bifacial dual-glass** design, these modules also absorb radiation from the rear side, significantly increasing total energy yield, especially on surfaces with high albedo. This solution is a direct response to the needs of investors seeking maximum power density while maintaining the highest mechanical durability. The use of **SMBB technology** improves current flow and minimizes resistance losses, distinguishing this model from standard market solutions. These panels are primarily dedicated to large-scale photovoltaic farms and industrial installations where the lowest levelized cost of energy (LCOE) matters. The robust construction resistant to extreme weather conditions makes this series perform excellently in harsh environments, reducing the risk of micro-cracks. By choosing these modules, you gain the assurance of operation based on a **high bifaciality factor**, making them one of the most cost-effective options in the premium segment for the professional energy sector. ## Notable figures - At 23.2% efficiency, this panel is on par with typical \*\*HJT 700-750W\*\* modules - Power density of 231.8 W/m² matches the \*\*HJT 700-750W\*\* median - At -0.24%/°C, hot weather performance is typical for \*\*HJT 700-750W\*\* panels - Bifaciality factor of 90% can add 4-14% extra yield with reflective mounting surface - In the top 9% for efficiency among all HJT panels ## Questions ### What warranty does the GCL-NH12/66GDF series carry and what does it cover? The GCL-NH12/66GDF series comes with a 15-year product warranty covering material and workmanship defects, along with a 30-year linear power output warranty. After 30 years of operation, the module retains at least 88.27% of its nominal power output. This extended power warranty horizon is made possible by n-type TOPCon cells, which exhibit exceptionally low annual degradation rates, directly translating into predictable return on investment for utility-scale farms and industrial installations. ### Are GCL-NH12/66GDF modules suitable for large-scale solar farms or only for small installations? The GCL-NH12/66GDF series is designed primarily for utility-scale PV farms and industrial installations. A maximum power output of up to 720 Wp and module efficiency of up to 23.2% deliver high power density per unit area. The bifacial dual-glass construction further increases total energy yield, lowering the levelized cost of energy (LCOE) and shortening the investment payback period in the utility-scale segment. ### How does the bifacial dual-glass design work in the GCL-NH12/66GDF series and how much additional energy can be gained? The GCL-NH12/66GDF bifacial module generates electricity from both its front and rear surfaces by absorbing light reflected from the ground or surrounding surfaces. On light-colored ground, white roofing membranes, or snow-covered terrain, the additional rear-side yield can range from a few to over ten percent annually. The two glass layers replace the conventional backsheet, significantly improving mechanical durability and protecting the cells against moisture ingress throughout the full 30-year service life. ### What is the temperature coefficient of the GCL-NH12/66GDF and does the panel lose power on hot days? The GCL-NH12/66GDF series achieves a Pmax temperature coefficient of -0.24%/°C, placing it among the top performers on the market. By comparison, older p-type PERC modules typically exhibit -0.35%/°C. In practice, this means that during summer months, when cell temperature exceeds 25°C, GCL-NH12/66GDF modules produce noticeably more energy than standard modules — an advantage that is particularly pronounced during extended, high-irradiance summer seasons. ### What is the SMBB technology used in the GCL-NH12/66GDF and why is it superior to conventional busbars? SMBB, or Super Multi Busbar, is a cell interconnection approach in which cells are connected by a large number of very thin conductors instead of the 5 or 6 wide busbars used in conventional designs. This shortens the current path, reducing resistive losses within the cell. The thinner conductors also reduce mechanical stress on the cell, minimizing the risk of micro-cracks during transportation, installation, and long-term operation under demanding weather conditions. ### How much does the GCL-NH12/66GDF module weigh and do I need a reinforced mounting structure? The GCL-NH12/66GDF module weighs approximately 37.9 kg with dimensions of 2384 × 1303 × 33 mm. It is heavier than a typical backsheet module due to its dual-glass construction, so it is advisable to verify the load-bearing capacity of the roof or ground-mount substructure with a structural engineer before purchase. For ground-mount farms and utility-scale installations, the greater rigidity of the dual-glass frame is an advantage, as it provides superior resistance to high winds and hail loads without risk of deformation. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/NH-1266GDF-5baf6de6d247.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | -40 W, lighter, +2.0 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | -45 W, lighter, +1.8 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | Hotter, lighter, +1.8 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | -25 W, lighter, +1.7 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | -50 W, lighter, +1.6 pp | | [Longi Solar LR7-72HVHF-670M](https://comparepv.com/panel/longi-lr7-72hvhf-670m) | 670 W | -50 W, lighter, +1.6 pp | | [Jinko Solar JKM650-670N-66QL6-BDV (670W class)](https://comparepv.com/panel/jinko-solar-jkm650-670n-66ql6-bdv-670w-class) | 670 W | -50 W, lighter, +1.6 pp | | [GCL GCL-M12/66GDF-655W](https://comparepv.com/panel/gcl-gcl-m12-66gdf-655w) | 655 W | -65 W, hotter, -2.1 pp | | [GCL GCL-M12/66H-660W](https://comparepv.com/panel/gcl-gcl-m12-66h-660w) | 660 W | -60 W, hotter, -2.0 pp | | [GCL GCL-M12/66H-665W](https://comparepv.com/panel/gcl-gcl-m12-66h-665w) | 665 W | -55 W, hotter, -1.8 pp | | [AIKO AIKO-A805-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a805-grh78dw) | 805 W | +85 W, hotter, +1.9 pp | | [AIKO AIKO-A800-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a800-grh78dw) | 800 W | +80 W, hotter, +1.7 pp | | [AIKO AIKO-A795-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a795-grh78dw) | 795 W | +75 W, hotter, +1.6 pp | | [AIKO AIKO-A790-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a790-grh78dw) | 790 W | +70 W, hotter, +1.4 pp | | [Trina Solar TSM-NEG21C.20Q-760](https://comparepv.com/panel/trina-solar-tsm-neg21c-20q-760) | 760 W | +40 W, hotter, +1.3 pp | | [AIKO AIKO-A785-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a785-grh78dw) | 785 W | +65 W, hotter, +1.2 pp | --- Source: https://comparepv.com/panel/gcl-gcl-nh12-66gdf-720 Not in this file, on the page: the I-V and temperature curves lifted from the manufacturer's datasheet, a thirty-year output simulator, a bifacial gain calculator and alternatives filtered by how closely they match these dimensions.