--- title: "Resun Solar RS8V-M-420W FULL BLACK vs Resun Solar RS9H-M TOPCON-725 - Solar Panel Comparison | ComparePV" description: "Compare Resun Solar RS8V-M-420W FULL BLACK vs Resun Solar RS9H-M TOPCON-725 side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/resun-solar-rs8v-m-420w-full-black/resun-solar-rs9h-m-topcon-725" updated: 2026-09-11 --- # Resun Solar RS8V-M-420W FULL BLACK vs Resun Solar RS9H-M TOPCON-725 RS9H-M TOPCON-725 leads on the differences that matter The largest is module efficiency: 1.83 pp more efficient. 5 of 19 comparable parameters are identical. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [Resun Solar RS8V-M-420W FULL BLACK](https://comparepv.com/panel/resun-solar-rs8v-m-420w-full-black) | [Resun Solar RS9H-M TOPCON-725](https://comparepv.com/panel/resun-solar-rs9h-m-topcon-725) | | Manufacturer | Resun Solar | Resun Solar | | Power | 420 Wp | 725 Wp | | Efficiency | 21.51 % | 23.34 % | | Technology | TOPCon | TOPCon | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | RS8V-M-420W FULL BLACK | RS9H-M TOPCON-725 | Difference | | --- | --- | --- | --- | | Module efficiency | 21.51 % | 23.34 % | +1.83 pp for RS9H-M TOPCON-725 | | Temperature coefficient | -0.250 %/°C | -0.300 %/°C | +0.050 %/°C for RS8V-M-420W FULL BLACK | | Rated power | 420 Wp | 725 Wp | +305 W for RS9H-M TOPCON-725 | | Power density | 215.1 Wp/m² | 233.4 Wp/m² | +18.3 Wp/m² for RS9H-M TOPCON-725 | | Weight | 21.5 kg | 32.3 kg | -10.8 kg for RS8V-M-420W FULL BLACK | | Weight per kWp | 51.2 kg/kWp | 44.6 kg/kWp | -6.6 kg/kWp for RS9H-M TOPCON-725 | | Open-circuit voltage | 37.58 V | 49.60 V | 12.02 V apart | | Short-circuit current | 14.11 A | 18.54 A | 4.43 A apart | | Module area | 1.953 m² | 3.106 m² | 1.154 m² apart | | Annual degradation | 0.40 %/yr | 0.50 %/yr | -0.10 %/yr for RS8V-M-420W FULL BLACK | | Voltage at max power | 31.78 V | 41.50 V | 9.72 V apart | | Current at max power | 13.22 A | 17.47 A | 4.25 A apart | | Cell count | 108 | 132 | 24 cells apart | | Dimensions | 1722x1134x30 mm | 2384x1303x30 mm | 1722x1134x30 mm vs 2384x1303x30 mm | ## Every compared parameter | Parameter | RS8V-M-420W FULL BLACK | RS9H-M TOPCON-725 | | --- | --- | --- | | Rated power | 420 Wp | 725 Wp | | Module efficiency | 21.51 % | 23.34 % | | Power density | 215.1 Wp/m² | 233.4 Wp/m² | | Open-circuit voltage | 37.58 V | 49.60 V | | Voltage at max power | 31.78 V | 41.50 V | | Short-circuit current | 14.11 A | 18.54 A | | Current at max power | 13.22 A | 17.47 A | | Temperature coefficient | -0.250 %/°C | -0.300 %/°C | | Dimensions | 1722x1134x30 mm | 2384x1303x30 mm | | Module area | 1.953 m² | 3.106 m² | | Weight | 21.5 kg | 32.3 kg | | Weight per kWp | 51.2 kg/kWp | 44.6 kg/kWp | | Product warranty | 15 yrs | 15 yrs | | Performance warranty | 30 yrs | 30 yrs | | Annual degradation | 0.40 %/yr | 0.50 %/yr | | Cell technology | TOPCon | TOPCon | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 108 | 132 | | Bifacial | No | No | ## Thirty-year yield Declared annual degradation, with a 1.0% first-year loss assumed for both panels because at least one datasheet omits it, at 1,200 kWh/kWp a year - **Cumulative output, RS8V-M-420W FULL BLACK:** 14,092 kWh - **Cumulative output, RS9H-M TOPCON-725:** 23,947 kWh - **Gap:** 9,855 kWh ## Output when hot | Condition | Cell temperature | RS8V-M-420W FULL BLACK | RS9H-M TOPCON-725 | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 420 W | 725 W | 100.0% of rated power | | Cool, bright day | 40 °C | 404 W | 692 W | 95.5% of rated power | | Typical summer roof | 55 °C | 389 W | 660 W | 91.0% of rated power | | Hot roof | 70 °C | 373 W | 627 W | 86.5% of rated power | ## Against the whole database | Measure | RS8V-M-420W FULL BLACK | RS9H-M TOPCON-725 | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #7,894 | #943 | 14,005 | RS9H-M TOPCON-725 leads by 6,951 places | | Power density | #7,882 | #936 | 14,005 | RS9H-M TOPCON-725 leads by 6,946 places | | Heat behaviour | #456 | #6,093 | 14,005 | RS8V-M-420W FULL BLACK leads by 5,637 places | | Weight | #4,567 | #473 | 14,005 | RS9H-M TOPCON-725 leads by 4,094 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #10,194 | #242 | 14,005 | RS9H-M TOPCON-725 leads by 9,952 places | ## Questions ### Which panel is better: Resun Solar RS8V-M-420W FULL BLACK or Resun Solar RS9H-M TOPCON-725? According to our database: **Resun Solar RS9H-M TOPCON-725** has higher module efficiency (**23.34%** vs **21.51%**); **Resun Solar RS8V-M-**420 W** FULL BLACK** tolerates heat better (temp coeff **-0.250%/°C** vs **-0.300%/°C**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of Resun Solar RS8V-M-420W FULL BLACK and Resun Solar RS9H-M TOPCON-725? **Resun Solar RS8V-M-**420 W** FULL BLACK** has a module efficiency of **21.51%**, while **Resun Solar RS9H-M TOPCON-725** is **23.34%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does Resun Solar RS8V-M-420W FULL BLACK use vs Resun Solar RS9H-M TOPCON-725? **Resun Solar RS8V-M-**420 W** FULL BLACK** uses **TOPCon** cells; **Resun Solar RS9H-M TOPCON-725** 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 Resun Solar RS8V-M-420W FULL BLACK and Resun Solar RS9H-M TOPCON-725? **Resun Solar RS8V-M-**420 W** FULL BLACK** has a **30 years** power warranty; **Resun Solar RS9H-M TOPCON-725** 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. ## Related comparisons - [Resun Solar RS8V-M-420W FULL BLACK vs Resun Solar RS8V-M-435W FULL BLACK](https://comparepv.com/compare/resun-solar-rs8v-m-420w-full-black/resun-solar-rs8v-m-435w-full-black) - 3 differences, the largest is module efficiency - [Resun Solar RS8V-M-420W FULL BLACK vs Resun Solar RS8V-M-430W FULL BLACK](https://comparepv.com/compare/resun-solar-rs8v-m-420w-full-black/resun-solar-rs8v-m-430w-full-black) - 3 differences, the largest is module efficiency - [Resun Solar RS8V-M-420W FULL BLACK vs Resun Solar RS8V-M-425W FULL BLACK](https://comparepv.com/compare/resun-solar-rs8v-m-420w-full-black/resun-solar-rs8v-m-425w-full-black) - One difference: module efficiency - [Resun Solar RS9H-M TOPCON-725 vs Resun Solar RS9H-M TOPCON-735](https://comparepv.com/compare/resun-solar-rs9h-m-topcon-725/resun-solar-rs9h-m-topcon-735) - 3 differences, the largest is module efficiency - [Resun Solar RS9H-M TOPCON-725 vs Resun Solar RS9H-M TOPCON-730](https://comparepv.com/compare/resun-solar-rs9h-m-topcon-725/resun-solar-rs9h-m-topcon-730) - The same specification on paper - [Resun Solar RS9H-M TOPCON-725 vs Resun Solar RS9H-M TOPCON-720](https://comparepv.com/compare/resun-solar-rs9h-m-topcon-725/resun-solar-rs9h-m-topcon-720) - The same specification on paper --- Source: https://comparepv.com/compare/resun-solar-rs8v-m-420w-full-black/resun-solar-rs9h-m-topcon-725 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.