--- title: "GL Solar 3SHBGH-C#-620 vs GL Solar 3SHBGH-C#-640 - Solar Panel Comparison | ComparePV" description: "Compare GL Solar 3SHBGH-C#-620 vs GL Solar 3SHBGH-C#-640 side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/gl-solar-3shbgh-c-620/gl-solar-3shbgh-c-640" updated: 2026-09-11 --- # GL Solar 3SHBGH-C#-620 vs GL Solar 3SHBGH-C#-640 640 leads on the differences that matter The largest is module efficiency: 0.70 pp more efficient. 16 of 19 comparable parameters are identical. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [GL Solar 3SHBGH-C#-620](https://comparepv.com/panel/gl-solar-3shbgh-c-620) | [GL Solar 3SHBGH-C#-640](https://comparepv.com/panel/gl-solar-3shbgh-c-640) | | Manufacturer | GL Solar | GL Solar | | Power | 620 Wp | 640 Wp | | Efficiency | 21.90 % | 22.60 % | | Technology | HJT | HJT | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | 620 | 640 | Difference | | --- | --- | --- | --- | | Module efficiency | 21.90 % | 22.60 % | +0.70 pp for 640 | | Power density | 219.1 Wp/m² | 226.1 Wp/m² | +7.1 Wp/m² for 640 | | Rated power | 620 Wp | 640 Wp | +20 W for 640 | ## Every compared parameter | Parameter | 620 | 640 | | --- | --- | --- | | Rated power | 620 Wp | 640 Wp | | Module efficiency | 21.90 % | 22.60 % | | Power density | 219.1 Wp/m² | 226.1 Wp/m² | | Open-circuit voltage | 45.49 V | 45.70 V | | Voltage at max power | 38.12 V | 38.91 V | | Short-circuit current | 17.40 A | 17.56 A | | Current at max power | 16.26 A | 16.46 A | | Temperature coefficient | -0.260 %/°C | -0.260 %/°C | | Dimensions | 2172x1303x35 mm | 2172x1303x35 mm | | Module area | 2.830 m² | 2.830 m² | | Weight | 36.0 kg | 36.0 kg | | Weight per kWp | 58.1 kg/kWp | 56.2 kg/kWp | | Product warranty | 15 yrs | 15 yrs | | Performance warranty | 30 yrs | 30 yrs | | Annual degradation | 0.40 %/yr | 0.40 %/yr | | Cell technology | HJT | HJT | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 120 | 120 | | 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 (-0.260 %/°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, 620:** 20,579 kWh - **Cumulative output, 640:** 21,243 kWh - **Gap:** 664 kWh ## Output when hot | Condition | Cell temperature | 620 | 640 | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 620 W | 640 W | 100.0% of rated power | | Cool, bright day | 40 °C | 596 W | 615 W | 96.1% of rated power | | Typical summer roof | 55 °C | 572 W | 590 W | 92.2% of rated power | | Hot roof | 70 °C | 547 W | 565 W | 88.3% of rated power | ## Against the whole database | Measure | 620 | 640 | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #6,783 | #3,658 | 14,005 | 640 leads by 3,125 places | | Power density | #6,743 | #3,681 | 14,005 | 640 leads by 3,062 places | | Heat behaviour | #511 | #511 | 14,005 | Tied - the same position in the database | | Weight | #11,548 | #10,518 | 14,005 | 640 leads by 1,030 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #3,210 | #1,906 | 14,005 | 640 leads by 1,304 places | ## Questions ### Which panel is better: GL Solar 3SHBGH-C#-620 or GL Solar 3SHBGH-C#-640? According to our database: **GL Solar 3SHBGH-C#-640** has higher module efficiency (**22.60%** vs **21.90%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of GL Solar 3SHBGH-C#-620 and GL Solar 3SHBGH-C#-640? **GL Solar 3SHBGH-C#-620** has a module efficiency of **21.90%**, while **GL Solar 3SHBGH-C#-640** is **22.60%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does GL Solar 3SHBGH-C#-620 use vs GL Solar 3SHBGH-C#-640? **GL Solar 3SHBGH-C#-620** uses **HJT** cells; **GL Solar 3SHBGH-C#-640** uses **HJT**. 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 GL Solar 3SHBGH-C#-620 and GL Solar 3SHBGH-C#-640? **GL Solar 3SHBGH-C#-620** has a **30 years** power warranty; **GL Solar 3SHBGH-C#-640** 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 GL Solar 3SHBGH-C#-620 and GL Solar 3SHBGH-C#-640 bifacial panels? Both **GL Solar 3SHBGH-C#-620** and **GL Solar 3SHBGH-C#-640** 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 - [GL Solar 3SHBGH-C#-620 vs GL Solar 3SHBGH-C#-635](https://comparepv.com/compare/gl-solar-3shbgh-c-620/gl-solar-3shbgh-c-635) - 3 differences, the largest is module efficiency - [GL Solar 3SHBGH-C#-620 vs GL Solar 3SHBGH-C#-630](https://comparepv.com/compare/gl-solar-3shbgh-c-620/gl-solar-3shbgh-c-630) - 3 differences, the largest is module efficiency - [GL Solar 3SHBGH-C#-620 vs GL Solar 3SHBGH-C#-625](https://comparepv.com/compare/gl-solar-3shbgh-c-620/gl-solar-3shbgh-c-625) - One difference: module efficiency - [GL Solar 3SHBGH-C#-620 vs GL Solar 3SHBGH-C#-615](https://comparepv.com/compare/gl-solar-3shbgh-c-620/gl-solar-3shbgh-c-615) - One difference: module efficiency - [GL Solar 3SHBGH-C#-620 vs GL Solar 3SHBGH-C#-610](https://comparepv.com/compare/gl-solar-3shbgh-c-620/gl-solar-3shbgh-c-610) - 3 differences, the largest is module efficiency - [GL Solar 3SHBGH-C#-620 vs GL Solar HY-NT10/72GDF-610W](https://comparepv.com/compare/gl-solar-3shbgh-c-620/gl-solar-hy-nt10-72gdf-610w) - 14 differences, the largest is module efficiency --- Source: https://comparepv.com/compare/gl-solar-3shbgh-c-620/gl-solar-3shbgh-c-640 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.