--- title: "Resun Solar RS8I-M TOPCON-425 425W Solar Panel - Specs & Review | ComparePV" description: "Resun Solar RS8I-M TOPCON-425 425W solar panel. Specs: 21.27% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/resun-solar-rs8i-m-topcon-425" updated: 2026-09-11 --- # Resun Solar RS8I-M TOPCON-425 Middle of its segment, modest efficiency 1,218 panels in the segment TOPCon 400-450 W ## Identity - **Manufacturer:** Resun Solar - **Model:** RS8I-M TOPCON-425 - **Series:** RS8I-M TOPCON - **Rated power:** 425 W - **Cell technology:** TOPCon ## How it compares Compared against segment TOPCon 400-450 W (1218 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 425 W | 435 W | Typical | | | Module efficiency | 21.27% | 22.00% | Weak - bottom 10% | 8,849 | | Power density | 212.7 | 220.2 | Weak - bottom 13% | 8,733 | | Temperature coefficient | -0.300 | -0.290 | Typical | 6,093 | | Weight (kg) | 22.3 kg | 22.0 kg | Typical | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 21.27% | 22.00% | Weak - bottom 10% | 8,849 | | Power density | 212.7 | 220.2 | Weak - bottom 13% | 8,733 | | Temperature coefficient | -0.300 | -0.290 | Typical | 6,093 | | Weight per kWp | 52.5 | 51.4 | Typical | 6,006 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Watch out for - **21.27% module efficiency** - Bottom 10% of the TOPCon 400-450 W segment, against a median of 22.00%. - **212.7 watts per square metre** - Bottom 13% of the TOPCon 400-450 W segment, against a median of 220.2. - **Best for:** Commercial, utility-scale, shaded-installations and hot-climate. - **Not ideal for:** Tight roof space and roofs where every square metre has to count. ## Specification ### Electrical - **Rated power (Pmax):** 425 W - **Efficiency:** 21.27 % - **Voltage at Pmax (Vmp):** 43.11 V - **Current at Pmax (Imp):** 9.86 A - **Open-circuit voltage (Voc):** 51.20 V - **Short-circuit current (Isc):** 10.55 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.300 %/degC - **Temperature coefficient of Voc:** -0.250 %/degC - **Temperature coefficient of Isc:** 0.045 %/degC - **NOCT:** 45 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** TOPCon - **Cell count:** 144 ### Physical - **Length:** 1762 mm - **Width:** 1134 mm - **Thickness:** 35 mm - **Weight:** 22.3 kg - **Area:** 2.00 m2 - **Power density:** 212.7 Wp/m2 ### Warranty and degradation - **Product warranty:** 15 years - **Performance warranty:** 30 years - **Annual degradation:** 0.50 % - **Output after 30 years:** 359 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 8849 of 14005 | | Power density | 8733 of 14005 | | Temperature coefficient | 6093 of 14005 | | Weight | 6006 of 14005 | | Warranty | 21 of 14005 | ## About this series The **Resun Solar RS8I-M TOPCon** series is built for installations where every square meter of roof or ground space counts. The panel is based on **N-type TOPCon cells** in a half-cut configuration, which reduces power losses from partial shading and delivers better performance stability at high temperatures compared to conventional PERC modules. The applied **multi-busbar** technology improves current collection across the cell surface and strengthens interconnection reliability, meaningfully lowering the risk of microcracks and long-term degradation. The RS8I-M series is well suited both for residential rooftop installations and smaller commercial projects, where high productivity is expected despite limited mounting area. Thanks to its **low temperature coefficient**, the panels maintain output even on hot days, translating into higher real-world energy yield compared to older technologies. The manufacturer backs build quality with a long-term **product and power warranty**, along with certifications confirming compliance with international safety and performance standards, including verified resistance to PID degradation. This is a solid choice for investors seeking proven TOPCon technology at a reasonable price-to-performance ratio. ## Notable figures - At 21.3% efficiency, this panel is 0.7pp below the \*\*TOPCon 400-450W\*\* median of 22.0% - 212.7 W/m² power density is 7.5 W/m² below \*\*TOPCon 400-450W\*\* median (220.2 W/m²) - requires larger installation area - At -0.30%/°C, hot weather performance is typical for \*\*TOPCon 400-450W\*\* panels - In the top 63% for efficiency among all TOPCon panels ## Questions ### What is the maximum power output of the Resun Solar RS8I-M TOPCon panel? Modules from the RS8I-M TOPCon series reach a maximum power output of up to 630 Wp. This is achieved through N-type TOPCon half-cut cells combined with multi-busbar technology, which increase the active surface area and current collection efficiency. This means a higher energy yield per roof area compared to classic PERC panels of similar dimensions. ### Are RS8I-M TOPCon panels bifacial? No, the RS8I-M TOPCon series consists of mono-facial modules optimized for standard rooftop and ground-mounted installations without relying on reflected light from the ground. If additional energy gain from the rear side is a priority, the manufacturer's bifacial lineup should be considered instead, but for typical residential installations a mono-facial panel is more than sufficient. ### What warranty comes with the Resun Solar RS8I-M TOPCon series? The manufacturer provides a 15-year product warranty and a 30-year linear power output warranty. This means that over three decades of operation, the panel maintains a guaranteed percentage of its original power, while manufacturing or material defects are covered during the first 15 years. This is a standard benchmark for modern TOPCon-based modules. ### How does TOPCon technology in the RS8I-M differ from classic PERC panels? The N-type TOPCon cells used in the RS8I-M have lower recombination losses and better surface passivation than P-type PERC cells, resulting in higher efficiency and slower power degradation over time. TOPCon also handles high operating temperatures better, so during hot weather on a heated roof, the panel loses less power than a comparable PERC module. ### Do RS8I-M TOPCon panels perform well on hot days? Yes, thanks to the low temperature coefficient of TOPCon cells, RS8I-M modules lose less power as operating temperature rises compared to older PERC technology. In practice this means a higher real-world energy yield in summer, when rooftop panels can heat up to 60-70 degrees Celsius, making this an important advantage in warmer climates. ### Is RS8I-M TOPCon a good choice for a small rooftop installation? Yes, the high power output per single module (up to 630 Wp) makes the RS8I-M series particularly suitable for limited roof space where maximizing total system power matters. Fewer panels are needed to reach the target capacity, which also means faster installation and fewer mounting points on the roof structure. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/RS8I-M-425-460W-TOPCON-80cc1c421188.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Maxeon SPR-MAX7-475](https://comparepv.com/panel/maxeon-spr-max7-475) | 475 W | +50 W, +2.7 pp, +10 yr warranty | | [Just Solar JST-EDMH-(445-465)W-TD (465W class)](https://comparepv.com/panel/just-solar-jst-edmh-445-465-w-td-465w-class) | 465 W | +40 W, lighter, +2.5 pp | | [JA Solar JAT54S40-475/LR](https://comparepv.com/panel/ja-solar-jat54s40-475-lr) | 475 W | +50 W, cooler, +2.5 pp | | [Tongwei TWMNH-48HW475](https://comparepv.com/panel/tongwei-solar-twmnh-48hw475) | 475 W | +50 W, cooler, +2.5 pp | | [Astronergy CHSM48RN(DG)/F-BH-475](https://comparepv.com/panel/astronergy-chint-new-energy-technology-co-ltd-chsm48rn-dg-f-bh-475) | 475 W | +50 W, heavier, +2.5 pp | | [AIKO AIKO-A475-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a475-mce54mw) | 475 W | +50 W, cooler, +2.5 pp | | [AIKO AIKO-A475-MAH54Mw](https://comparepv.com/panel/aiko-aiko-a475-mah54mw) | 475 W | +50 W, cooler, +2.5 pp | | [Resun Solar RS8I-M TOPCON-430](https://comparepv.com/panel/resun-solar-rs8i-m-topcon-430) | 430 W | +0.2 pp | | [Resun Solar RS8I-M TOPCON-435](https://comparepv.com/panel/resun-solar-rs8i-m-topcon-435) | 435 W | +10 W, +0.5 pp | | [Resun Solar RS8I-M TOPCON-440](https://comparepv.com/panel/resun-solar-rs8i-m-topcon-440) | 440 W | +15 W, +0.8 pp | | [Resun Solar RS8I-M TOPCON-445](https://comparepv.com/panel/resun-solar-rs8i-m-topcon-445) | 445 W | +20 W, +1.0 pp | | [Resun Solar RS8I-M TOPCON-450](https://comparepv.com/panel/resun-solar-rs8i-m-topcon-450) | 450 W | +25 W, +1.2 pp | | [Resun Solar RS8I-M TOPCON-455](https://comparepv.com/panel/resun-solar-rs8i-m-topcon-455) | 455 W | +30 W, +1.5 pp | | [Resun Solar RS8I-M TOPCON-460](https://comparepv.com/panel/resun-solar-rs8i-m-topcon-460) | 460 W | +35 W, +1.8 pp | | [Longi Solar LR7-54HJD-510M](https://comparepv.com/panel/longi-lr7-54hjd-510m) | 510 W | +85 W, cooler, +3.7 pp | | [AIKO AIKO-A495-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a495-mce54mw) | 495 W | +70 W, cooler, +3.5 pp | --- Source: https://comparepv.com/panel/resun-solar-rs8i-m-topcon-425 Not in this file, on the page: the I-V and temperature curves lifted from the manufacturer's datasheet, a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.