--- title: "GCL NT12R/54BGDF-515W vs GCL NT12R/54GDF-520W - Solar Panel Comparison | ComparePV" description: "Compare GCL NT12R/54BGDF-515W vs GCL NT12R/54GDF-520W side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/gcl-nt12r-54bgdf-515w/gcl-nt12r-54gdf-520w" updated: 2026-09-11 --- # GCL NT12R/54BGDF-515W vs GCL NT12R/54GDF-520W 54GDF-520W leads on the differences that matter The largest is module efficiency: 0.22 pp more efficient. 16 of 19 comparable parameters are identical. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [GCL NT12R/54BGDF-515W](https://comparepv.com/panel/gcl-nt12r-54bgdf-515w) | [GCL NT12R/54GDF-520W](https://comparepv.com/panel/gcl-nt12r-54gdf-520w) | | Manufacturer | GCL | GCL | | Power | 515 Wp | 520 Wp | | Efficiency | 23.15 % | 23.37 % | | Technology | TOPCon | TOPCon | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | 54BGDF-515W | 54GDF-520W | Difference | | --- | --- | --- | --- | | Module efficiency | 23.15 % | 23.37 % | +0.22 pp for 54GDF-520W | | Short-circuit current | 15.50 A | 16.11 A | 0.61 A apart | | Open-circuit voltage | 41.19 V | 40.05 V | 1.14 V apart | ## Every compared parameter | Parameter | 54BGDF-515W | 54GDF-520W | | --- | --- | --- | | Rated power | 515 Wp | 520 Wp | | Module efficiency | 23.15 % | 23.37 % | | Power density | 231.5 Wp/m² | 233.7 Wp/m² | | Open-circuit voltage | 41.19 V | 40.05 V | | Voltage at max power | 34.75 V | 33.99 V | | Short-circuit current | 15.50 A | 16.11 A | | Current at max power | 14.82 A | 15.30 A | | Temperature coefficient | -0.290 %/°C | -0.290 %/°C | | Dimensions | 1962x1134x30 mm | 1962x1134x30 mm | | Module area | 2.225 m² | 2.225 m² | | Weight | 27.3 kg | 27.3 kg | | Weight per kWp | 53.0 kg/kWp | 52.5 kg/kWp | | Product warranty | 12 yrs | 12 yrs | | Performance warranty | 30 yrs | 30 yrs | | Annual degradation | 0.40 %/yr | 0.40 %/yr | | Cell technology | TOPCon | TOPCon | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 108 | 108 | | Bifacial | Yes | Yes | ## Thirty-year yield Each panel's own declared degradation curve, at 1,200 kWh/kWp a year Same temp coeff. for both panels (-0.290 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other. - **Cumulative output, 54BGDF-515W:** 17,279 kWh - **Cumulative output, 54GDF-520W:** 17,447 kWh - **Gap:** 168 kWh ## Output when hot | Condition | Cell temperature | 54BGDF-515W | 54GDF-520W | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 515 W | 520 W | 100.0% of rated power | | Cool, bright day | 40 °C | 493 W | 497 W | 95.7% of rated power | | Typical summer roof | 55 °C | 470 W | 475 W | 91.3% of rated power | | Hot roof | 70 °C | 448 W | 452 W | 87.0% of rated power | ## Against the whole database | Measure | 54BGDF-515W | 54GDF-520W | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #1,503 | #930 | 14,005 | 54GDF-520W leads by 573 places | | Power density | #1,499 | #919 | 14,005 | 54GDF-520W leads by 580 places | | Heat behaviour | #2,165 | #2,165 | 14,005 | Tied - the same position in the database | | Weight | #6,762 | #6,043 | 14,005 | 54GDF-520W leads by 719 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #5,886 | #5,503 | 14,005 | 54GDF-520W leads by 383 places | ## Questions ### Which panel is better: GCL NT12R/54BGDF-515W or GCL NT12R/54GDF-520W? According to our database: **GCL NT12R/54GDF-**520 W**** has higher module efficiency (**23.37%** vs **23.15%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of GCL NT12R/54BGDF-515W and GCL NT12R/54GDF-520W? **GCL NT12R/54BGDF-**515 W**** has a module efficiency of **23.15%**, while **GCL NT12R/54GDF-**520 W**** is **23.37%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does GCL NT12R/54BGDF-515W use vs GCL NT12R/54GDF-520W? **GCL NT12R/54BGDF-**515 W**** uses **TOPCon** cells; **GCL NT12R/54GDF-**520 W**** uses **TOPCon**. Modern **n-type** technologies (**TOPCon**, **HJT**, BC) typically deliver higher efficiency and lower degradation compared to older **PERC** (p-type) cells. ### What is the warranty on GCL NT12R/54BGDF-515W and GCL NT12R/54GDF-520W? **GCL NT12R/54BGDF-**515 W**** has a **30 years** power warranty; **GCL NT12R/54GDF-**520 W**** has a **30 years** power warranty. The power warranty guarantees a minimum percentage of rated output at the end of the warranty period (typically 80**-87%**). Product (materials) warranties are usually shorter. ### Are GCL NT12R/54BGDF-515W and GCL NT12R/54GDF-520W bifacial panels? Both **GCL NT12R/54BGDF-**515 W**** and **GCL NT12R/54GDF-**520 W**** are bifacial - they capture reflected light from the ground, which can add 5**-15%** more annual energy on ground-mount or elevated rooftop installations with a light surface beneath. ## Related comparisons - [GCL NT12R/54BGDF-515W vs GCL GCL-NT12R/54GDF-530](https://comparepv.com/compare/gcl-nt12r-54bgdf-515w/gcl-gcl-nt12r-54gdf-530) - 5 differences, the largest is module efficiency - [GCL NT12R/54BGDF-515W vs GCL NT12R/54GDF-525W](https://comparepv.com/compare/gcl-nt12r-54bgdf-515w/gcl-nt12r-54gdf-525w) - 5 differences, the largest is module efficiency - [GCL NT12R/54BGDF-515W vs GCL GCL-NT12R/54GDF-525](https://comparepv.com/compare/gcl-nt12r-54bgdf-515w/gcl-gcl-nt12r-54gdf-525) - 5 differences, the largest is module efficiency - [GCL NT12R/54BGDF-515W vs GCL NT12R/54BGDF-520W](https://comparepv.com/compare/gcl-nt12r-54bgdf-515w/gcl-nt12r-54bgdf-520w) - One difference: module efficiency - [GCL NT12R/54BGDF-515W vs GCL GCL-NT12R/54GDF-520](https://comparepv.com/compare/gcl-nt12r-54bgdf-515w/gcl-gcl-nt12r-54gdf-520) - 3 differences, the largest is module efficiency - [GCL NT12R/54BGDF-515W vs GCL NT12R/54GDF-515W](https://comparepv.com/compare/gcl-nt12r-54bgdf-515w/gcl-nt12r-54gdf-515w) - 3 differences, the largest is open-circuit voltage --- Source: https://comparepv.com/compare/gcl-nt12r-54bgdf-515w/gcl-nt12r-54gdf-520w Not in this file, on the page: the thirty-year yield curve year by year at a cell temperature you pick and a written summary generated on request.