--- title: "Astronergy CHSM66RN(DG)/F-BH-635W vs Astronergy CHSM66RN(DG)/F-BH-645 - Solar Panel Comparison | ComparePV" description: "Compare Astronergy CHSM66RN(DG)/F-BH-635W vs Astronergy CHSM66RN(DG)/F-BH-645 side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-635w/astronergy-chsm66rn-dg-f-bh-645" updated: 2026-09-11 --- # Astronergy CHSM66RN(DG)/F-BH-635W vs Astronergy CHSM66RN(DG)/F-BH-645 645 leads on the differences that matter The largest is module efficiency: 0.40 pp more efficient. 16 of 19 comparable parameters are identical. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [Astronergy CHSM66RN(DG)/F-BH-635W](https://comparepv.com/panel/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-635w) | [Astronergy CHSM66RN(DG)/F-BH-645](https://comparepv.com/panel/astronergy-chsm66rn-dg-f-bh-645) | | Manufacturer | Astronergy | Astronergy | | Power | 635 Wp | 645 Wp | | Efficiency | 23.50 % | 23.90 % | | Technology | TOPCon | TOPCon | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | 635W | 645 | Difference | | --- | --- | --- | --- | | Module efficiency | 23.50 % | 23.90 % | +0.40 pp for 645 | | Power density | 235.1 Wp/m² | 238.8 Wp/m² | +3.7 Wp/m² for 645 | | Rated power | 635 Wp | 645 Wp | +10 W for 645 | ## Every compared parameter | Parameter | 635W | 645 | | --- | --- | --- | | Rated power | 635 Wp | 645 Wp | | Module efficiency | 23.50 % | 23.90 % | | Power density | 235.1 Wp/m² | 238.8 Wp/m² | | Open-circuit voltage | 49.42 V | 49.72 V | | Voltage at max power | 41.86 V | 42.11 V | | Short-circuit current | 16.35 A | 16.50 A | | Current at max power | 15.17 A | 15.32 A | | Temperature coefficient | -0.290 %/°C | -0.290 %/°C | | Dimensions | 2382x1134x30 mm | 2382x1134x30 mm | | Module area | 2.701 m² | 2.701 m² | | Weight | 31.6 kg | 31.6 kg | | Weight per kWp | 49.8 kg/kWp | 49.1 kg/kWp | | Product warranty | 15 yrs | 15 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 | 132 | 132 | | 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, 635W:** 21,306 kWh - **Cumulative output, 645:** 21,641 kWh - **Gap:** 335 kWh ## Output when hot | Condition | Cell temperature | 635W | 645 | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 635 W | 645 W | 100.0% of rated power | | Cool, bright day | 40 °C | 607 W | 617 W | 95.7% of rated power | | Typical summer roof | 55 °C | 580 W | 589 W | 91.3% of rated power | | Hot roof | 70 °C | 552 W | 561 W | 87.0% of rated power | ## Against the whole database | Measure | 635W | 645 | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #716 | #351 | 14,005 | 645 leads by 365 places | | Power density | #741 | #356 | 14,005 | 645 leads by 385 places | | Heat behaviour | #2,165 | #2,165 | 14,005 | Tied - the same position in the database | | Weight | #3,240 | #2,705 | 14,005 | 645 leads by 535 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #1,432 | #1,065 | 14,005 | 645 leads by 367 places | ## Questions ### Which panel is better: Astronergy CHSM66RN(DG)/F-BH-635W or Astronergy CHSM66RN(DG)/F-BH-645? According to our database: **Astronergy CHSM66RN(DG)/F-BH-645** has higher module efficiency (**23.90%** vs **23.50%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of Astronergy CHSM66RN(DG)/F-BH-635W and Astronergy CHSM66RN(DG)/F-BH-645? **Astronergy CHSM66RN(DG)/F-BH-**635 W**** has a module efficiency of **23.50%**, while **Astronergy CHSM66RN(DG)/F-BH-645** is **23.90%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does Astronergy CHSM66RN(DG)/F-BH-635W use vs Astronergy CHSM66RN(DG)/F-BH-645? **Astronergy CHSM66RN(DG)/F-BH-**635 W**** uses **TOPCon** cells; **Astronergy CHSM66RN(DG)/F-BH-645** 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 Astronergy CHSM66RN(DG)/F-BH-635W and Astronergy CHSM66RN(DG)/F-BH-645? **Astronergy CHSM66RN(DG)/F-BH-**635 W**** has a **30 years** power warranty; **Astronergy CHSM66RN(DG)/F-BH-645** 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 Astronergy CHSM66RN(DG)/F-BH-635W and Astronergy CHSM66RN(DG)/F-BH-645 bifacial panels? Both **Astronergy CHSM66RN(DG)/F-BH-**635 W**** and **Astronergy CHSM66RN(DG)/F-BH-645** 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 - [Astronergy CHSM66RN(DG)/F-BH-635W vs Astronergy CHSM66RN(DG)/F-BH-650W](https://comparepv.com/compare/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-635w/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-650w) - 3 differences, the largest is module efficiency - [Astronergy CHSM66RN(DG)/F-BH-635W vs Astronergy CHSM66RN(DG)/F-BH-650](https://comparepv.com/compare/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-635w/astronergy-chsm66rn-dg-f-bh-650) - 3 differences, the largest is module efficiency - [Astronergy CHSM66RN(DG)/F-BH-635W vs Astronergy CHSM66RN(DG)/F-BH-645W](https://comparepv.com/compare/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-635w/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-645w) - 3 differences, the largest is module efficiency - [Astronergy CHSM66RN(DG)/F-BH-635W vs Astronergy CHSM66RN(DG)/F-BH-640W](https://comparepv.com/compare/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-635w/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-640w) - One difference: module efficiency - [Astronergy CHSM66RN(DG)/F-BH-635W vs Astronergy CHSM66RN(DG)/F-BH-640](https://comparepv.com/compare/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-635w/astronergy-chsm66rn-dg-f-bh-640) - One difference: module efficiency - [Astronergy CHSM66RN(DG)/F-BH-635W vs Astronergy CHSM66RN(DG)/F-BH-635](https://comparepv.com/compare/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-635w/astronergy-chsm66rn-dg-f-bh-635) - The same specification on paper --- Source: https://comparepv.com/compare/astronergy-chint-new-energy-technology-co-ltd-chsm66rn-dg-f-bh-635w/astronergy-chsm66rn-dg-f-bh-645 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.