--- title: "GCL GCL-M12/60GDF-590 Solar Panel: Specs & Datasheet | ComparePV" description: "GCL GCL-M12/60GDF-590 solar panel. Specs: 20.80% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/gcl-gcl-m12-60gdf-590" image: "https://comparepv.com/og/panel/gcl-gcl-m12-60gdf-590.png" updated: 2026-09-11 --- # GCL GCL-M12/60GDF-590 Warranty pick, modest efficiency 589 panels in the segment PERC 550-600 W ## Identity - **Manufacturer:** GCL - **Model:** GCL-M12/60GDF-590 - **Series:** GCL-M12/60GDF - **Rated power:** 590 W - **Cell technology:** PERC - **Bifacial:** yes ## How it compares Compared against segment PERC 550-600 W (589 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 590 W | 560 W | Strong - top 17% | | | Module efficiency | 20.80% | 21.29% | Weak - bottom 13% | 10,533 | | Power density | 208.5 | 212.9 | Weak - bottom 15% | 10,435 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,489 | | Weight (kg) | 34.6 kg | 30.8 kg | Weak - bottom 20% | | | Performance warranty | 30 yrs | 27 yrs | Strong - top 25% | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 20.80% | 21.29% | Weak - bottom 13% | 10,533 | | Power density | 208.5 | 212.9 | Weak - bottom 15% | 10,435 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,489 | | Weight per kWp | 58.6 | 52.7 | Weak - bottom 20% | 11,913 | | Performance warranty | 30 yrs | 27 yrs | Strong - top 25% | 21 | ### Strengths - **30 year performance warranty** - Top 25% of the PERC 550-600 W segment, against a median of 27 yrs. ### Watch out for - **20.80% module efficiency** - Bottom 13% of the PERC 550-600 W segment, against a median of 21.29%. - **208.5 watts per square metre** - Bottom 15% of the PERC 550-600 W segment, against a median of 212.9. - **58.6 kg per kWp** - Bottom 20% of the PERC 550-600 W segment, against a median of 52.7. - **Best for:** Utility-scale, agrivoltaic and floating. - **Not ideal for:** Tight roof space, roofs where every square metre has to count and weight-limited structures. ## Specification ### Electrical - **Rated power (Pmax):** 590 W - **Efficiency:** 20.80 % - **Voltage at Pmax (Vmp):** 34.15 V - **Current at Pmax (Imp):** 17.28 A - **Open-circuit voltage (Voc):** 41.24 V - **Short-circuit current (Isc):** 18.36 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.350 %/degC - **Temperature coefficient of Voc:** -0.280 %/degC - **Temperature coefficient of Isc:** 0.050 %/degC - **NOCT:** 45 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** PERC - **Cell count:** 120 - **Bifacial:** yes - **Bifacial gain:** 10.00 ### Physical - **Length:** 2172 mm - **Width:** 1303 mm - **Thickness:** 33 mm - **Weight:** 34.6 kg - **Area:** 2.83 m2 - **Power density:** 208.5 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 85.0 % - **First-year degradation:** 2.00 % - **Annual degradation:** 0.45 % - **Output after 30 years:** 501 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 10533 of 14129 | | Power density | 10435 of 14129 | | Temperature coefficient | 10489 of 14129 | | Weight | 11913 of 14129 | | Warranty | 21 of 14129 | ## Pros - **Bifacial Dual-Glass - Tangible Yield Gain** - The bifacial dual-glass construction enables absorption of irradiance reflected from the ground surface (typical bifacial gain of 5-15% depending on albedo), directly increasing annual energy output compared to monofacial modules. Replacing the rear backsheet with glass also eliminates moisture ingress, reducing the risk of PID and laminate degradation over the long term. - **BNEF Tier 1 - Bankability Assurance** - GCL-SI is listed on the Bloomberg NEF Tier 1 index as one of the two largest PV module manufacturers in the world by installed capacity. This status is a prerequisite for non-recourse project finance on utility-scale PV plants and directly lowers the cost of capital for institutional investors. - **30-Year Linear Power Warranty** - The manufacturer guarantees power output retention for 30 years, exceeding the 25-year standard offered by several comparable series (e.g., Seraphim Seco). The extended warranty horizon improves DCF models and reduces residual risk for projects with long-tenor financing. - **Up to 21.6% Efficiency - Competitive Within the Segment** - A peak efficiency of 21.6% positions the series on par with the Techwise Summit and Seraphim Seco (both at 21.55%), delivering higher power density per m² and simplifying the achievement of design targets on land-constrained sites. - **M10/M12 Format - High Packing Density** - The 182 mm (M10/M12) cells arranged in a 60-cell half-cut configuration minimize resistive losses and hot-spot risk. In practice, this translates to a higher fill factor and more stable performance under partial shading conditions compared to legacy G1/G6 cell formats. ## Cons - **Product Warranty of Only 12 Years** - A 15-year product warranty is becoming the standard in the premium module segment (>590 Wp) - offered by manufacturers such as Vikram Solar SOMERA, among others. The GCL-M12/60GDF is covered for only 12 years, which may serve as a negotiating point when comparing bids in tenders that require longer component protection. - **P-type PERC Technology Against the N-type Expansion** - The series is based on P-type PERC cells (Pmax temperature coefficient: -0.35%/°C), while the market is increasingly offering N-type TOPCon modules with lower LID and superior temperature characteristics (typically -0.29 to -0.30%/°C). For projects with a long operational horizon, the difference in degradation can be measurable at the level of several percentage points of energy yield after 25 years. ## About this series The GCL GCL-M12/60GDF series are bifacial dual-sided modules designed to genuinely increase energy yield in installations where every additional percent of production counts - from large-scale PV farms to demanding agrivoltaic and floating projects. Thanks to the **bifacial dual-glass** construction, the panels can effectively utilize reflected light from the ground, helping to stabilize energy output under varying conditions and improving the overall profitability of the system. What sets this series apart is the use of monocrystalline cells in **PERC** technology and an architecture based on the **M12 (G12) format**, which supports high cell density and minimizes losses. In practice, this translates to higher energy production on limited surfaces and easier achievement of design goals without adding more modules. The series has been refined for reliability - notably through **PID resistance** and solutions that reduce the risk of micro-cracks and hot-spots. For investors, this means fewer service issues, greater predictability of system performance, and better protection of the financial outcome. ## Notable figures - At 20.8% efficiency, this panel is on par with typical \*\*PERC 550-600W\*\* modules - Power density of 208.5 W/m² is 4.4 W/m² below \*\*PERC 550-600W\*\* median (212.9 W/m²) - needs more roof space - At -0.35%/°C, hot weather performance is typical for \*\*PERC 550-600W\*\* panels - Weight of 34.6 kg is 3.8 kg above \*\*PERC 550-600W\*\* median (30.8 kg) - verify structural support - Bifaciality factor of 70% can add 4-10% extra yield with reflective mounting surface ## Questions ### What does bifacial dual-glass technology offer in the GCL-M12/60GDF series, and does it have a real impact on energy yield? Yes, bifacial dual-glass is one of the most significant features of this series. The panel generates electricity from both the front and rear surfaces by capturing light reflected from the ground (snow, light-colored soil, gravel). Under favorable albedo conditions, this can deliver anywhere from a few to over ten percent additional annual energy production. The dual-glass construction - replacing the conventional backsheet film - enhances durability and moisture resistance, which is particularly important in agrivoltaic and floating PV installations. ### What warranty does the GCL-M12/60GDF come with, and what exactly does it cover? The manufacturer provides a 12-year product warranty covering manufacturing defects and material failures, along with a 30-year linear power output warranty guaranteeing a minimum of 84.95% of rated power at the end of that period. A 30-year power warranty represents one of the stronger standards currently available on the market and provides meaningful long-term protection for the return on investment - both in commercial projects and utility-scale PV farms. ### Are the GCL-M12/60GDF panels suitable for a residential rooftop installation? This series is designed primarily for commercial and utility-scale installations. A single panel weighs approximately 34.8 kg and measures 2172 × 1303 mm - a G12 (M12) format that is noticeably larger and heavier than typical residential modules. Mounting on a pitched roof is technically feasible, but requires a reinforced racking structure and an experienced installation crew. For prosumer applications, lighter modules in a smaller format are generally a better fit. ### How does the GCL-M12/60GDF series perform on hot days, and what is its temperature coefficient? The power temperature coefficient is -0.35%/°C, meaning that for every degree Celsius the cell temperature rises above 25°C, output power decreases by 0.35%. At a cell temperature of 65°C, the power loss is approximately 14%. The NOCT for this series is 45°C, placing it within the typical range for monocrystalline PERC modules. A structural advantage of the dual-glass design is slightly improved ventilation and a slower rate of cell temperature rise compared to backsheet-based modules. ### Is GCL a Tier 1 manufacturer, and should I have any concerns about panel quality? Yes, GCL (GCL System Integration Technology Co., Ltd.) is classified as a Tier 1 manufacturer by independent rating agencies, including Bloomberg NEF. The company ranks among the largest PV cell producers in the world. The GCL-M12/60GDF series carries IEC 61215 and IEC 61730 certifications and features PID resistance, minimizing the risk of degradation under high system voltage conditions (up to 1500 V DC). ### Which installation types are the best fit for the GCL-M12/60GDF series - utility-scale PV farms, agrivoltaics, or floating PV? The GCL-M12/60GDF series is particularly well suited to ground-mounted PV farms, agrivoltaic systems, and floating PV installations. The dual-glass construction provides high resistance to moisture and corrosion - critical in direct contact with water or in intensively irrigated agricultural environments. The bifacial design increases energy yield on high-albedo surfaces such as light-colored soil or open water, while the high power output of up to 610 W per module helps optimize the number of modules needed within a constrained footprint. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/15684142016890b8aa98ef0-ec31419c30cf.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Longi Solar LR7-60HVH-560M](https://comparepv.com/panel/longi-lr7-60hvh-560m) | 560 W | Cooler, lighter, +4.0 pp | | [AIKO AIKO-A640-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a640-mae72mw) | 640 W | Cooler, lighter, +4.0 pp | | [Longi Solar LR7-60HVH-555M](https://comparepv.com/panel/longi-lr7-60hvh-555m) | 555 W | Cooler, lighter, +3.8 pp | | [AIKO AIKO-A635-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a635-mae72mw) | 635 W | Cooler, lighter, +3.8 pp | | [AIKO AIKO-A630-MAH72Dw](https://comparepv.com/panel/aiko-aiko-a630-mah72dw) | 630 W | +40 W, cooler, +3.6 pp | | [Longi Solar LR7-60HVHL-550M](https://comparepv.com/panel/longi-lr7-60hvhl-550m) | 550 W | Cooler, 18 kg lighter, +3.6 pp | | [GCL GCL-M12/60GDF-595](https://comparepv.com/panel/gcl-gcl-m12-60gdf-595) | 595 W | Very close match | | [GCL GCL-M12/60GDF-600](https://comparepv.com/panel/gcl-gcl-m12-60gdf-600) | 600 W | +10 W, +0.4 pp | | [GCL GCL-M12/60GDF-605](https://comparepv.com/panel/gcl-gcl-m12-60gdf-605) | 605 W | +15 W, +0.6 pp | | [Gamko New Energy GKA210N120](https://comparepv.com/panel/gamko-new-energy-gka210n120) | 680 W | +90 W, lighter, +3.2 pp | | [Gamko New Energy GKA210N120-675](https://comparepv.com/panel/gamko-new-energy-gka210n120-675) | 675 W | +85 W, lighter, +3.1 pp | | [Q-SUN Solar QN-670HJT-01](https://comparepv.com/panel/q-sun-solar-qn-670hjt-01) | 670 W | +80 W, cooler, +2.9 pp | | [Gamko New Energy GKA210N120-670](https://comparepv.com/panel/gamko-new-energy-gka210n120-670) | 670 W | +80 W, lighter, +2.9 pp | | [Q-SUN Solar QN-665HJT-01](https://comparepv.com/panel/q-sun-solar-qn-665hjt-01) | 665 W | +75 W, cooler, +2.7 pp | | [Gamko New Energy GKA210N120-665](https://comparepv.com/panel/gamko-new-energy-gka210n120-665) | 665 W | +75 W, lighter, +2.7 pp | | [Sunpro Power SPDG660-N120M12](https://comparepv.com/panel/sunpro-spdg660-n120m12) | 660 W | +70 W, cooler, +2.5 pp | --- Source: https://comparepv.com/panel/gcl-gcl-m12-60gdf-590 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.