--- title: "WINAICO WST-505BKX54-A3 Solar Panel: Specs & Datasheet | ComparePV" description: "WINAICO WST-505BKX54-A3 solar panel. Specs: 24.70% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/winaico-wst-505bkx54-a3" image: "https://comparepv.com/og/panel/winaico-wst-505bkx54-a3.png" updated: 2026-11-05 --- # WINAICO WST-505BKX54-A3 Efficiency leader, no clear weak spot 36 panels in the segment Back Contact 500-550 W ## Identity - **Manufacturer:** WINAICO - **Model:** WST-505BKX54-A3 - **Series:** WBC Back Contact Series - **Rated power:** 505 W - **Cell technology:** Back Contact - **Bifacial:** yes ## How it compares Compared against segment Back Contact 500-550 W (36 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 505 W | 505 W | Typical | | | Module efficiency | 24.70% | 24.50% | Strong - top 11% | 51 | | Power density | 247.4 | 245.0 | Strong - top 11% | 51 | | Temperature coefficient | -0.260 | -0.260 | Typical | 521 | | Weight (kg) | 25.0 kg | 23.5 kg | Typical | | | Performance warranty | 30 yrs | 30 yrs | Typical | 31 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 24.70% | 24.50% | Strong - top 11% | 51 | | Power density | 247.4 | 245.0 | Strong - top 11% | 51 | | Temperature coefficient | -0.260 | -0.260 | Typical | 521 | | Weight per kWp | 49.5 | 46.5 | Typical | 3,070 | | Performance warranty | 30 yrs | 30 yrs | Typical | 31 | ### Strengths - **24.70% module efficiency** - Top 11% of the Back Contact 500-550 W segment, against a median of 24.50%. - **247.4 watts per square metre** - Top 11% of the Back Contact 500-550 W segment, against a median of 245.0. - **Best for:** Small roofs that need every watt and roofs where every square metre counts. ## Specification ### Electrical - **Rated power (Pmax):** 505 W - **Efficiency:** 24.70 % - **Voltage at Pmax (Vmp):** 34.08 V - **Current at Pmax (Imp):** 14.82 A - **Open-circuit voltage (Voc):** 40.88 V - **Short-circuit current (Isc):** 15.58 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.260 %/degC - **Temperature coefficient of Voc:** -0.220 %/degC - **Temperature coefficient of Isc:** 0.050 %/degC - **NOCT:** 45 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** Back Contact - **Cell count:** 108 - **Bifacial:** yes - **Bifacial gain:** 20.00 ### Physical - **Length:** 1800 mm - **Width:** 1134 mm - **Thickness:** 35 mm - **Weight:** 25.0 kg - **Area:** 2.04 m2 - **Power density:** 247.4 Wp/m2 ### Warranty and degradation - **Product warranty:** 30 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 88.8 % - **First-year degradation:** 1.00 % - **Annual degradation:** 0.35 % - **Output after 30 years:** 449 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 51 of 14269 | | Power density | 51 of 14269 | | Temperature coefficient | 521 of 14269 | | Weight | 3070 of 14269 | | Warranty | 31 of 14269 | ## Pros - **Highest efficiency in the back-contact segment** - At 24-24.7% efficiency, the WBC series clearly outperforms comparable back-contact modules: AE Solar AURORA MD-132 (21.29%), Sunova Tangra M Pro HD (22.7%), and Hiwatt HW-M12/100H (21%), all at the same 505 Wp maximum power. A lead of up to 3.4 percentage points means a smaller installed area is needed to reach the same system power. - **Clean aesthetics with no visible grid lines** - Moving all cell electrical contacts to the rear eliminates visible busbars and front-side metallization grid, yielding a uniform black surface. This is a genuine advantage for projects where facade or roof appearance matters as much as energy output. - **Bifacial glass-glass construction** - The glass-glass bifacial design captures light reflected off the mounting surface, boosting total energy yield, particularly on reflective ground surfaces and under variable irradiance conditions. - **30-year product and linear power warranty** - A full 30-year product warranty combined with a 30-year linear power warranty is among the longest coverage periods available in the PV market, exceeding the standard 25-year power warranties offered by many tier-1 manufacturers. - **Tier-1 manufacturer with 20+ years in the market** - WINAICO has operated since 2003 and holds tier-1 bankable status, improving project bankability and easing financing approval from banks and investment funds that require documented manufacturer stability. ## Cons - **Limited field track record for back-contact tech** - The WBC series launched in 2025, and back-contact modules as a category are still relatively young in mass production compared to established PERC and TOPCon technologies. This means less multi-year operational data from reference installations than for older cell architectures. - **Likely price premium over standard TOPCon modules** - Back-contact technology requires a more complex cell manufacturing process than standard half-cut PERC/TOPCon, which in the industry typically translates into a higher price per Wp. This can extend payback time compared to cheaper bifacial TOPCon modules of similar power. ## About this series The WINAICO WBC (Back Contact) series consists of solar modules where all electrical contacts of the cells are moved to the rear side of the structure, leaving the front surface completely free of busbars and metallic ribbons. The result is a uniform, **aesthetic black surface** with no visible wiring, making these panels a natural choice for projects where roof or facade design matters just as much as energy output. The use of **n-type monocrystalline half-cells** combined with back-contact architecture reduces optical and resistive losses, increasing the real energy yield from the same installed area. The **bifacial, glass-glass construction** further captures light reflected from the mounting surface, boosting overall system performance under varying irradiance conditions. Thanks to integrated bypass diodes, the panels handle partial shading more gracefully, limiting the power drops typical of conventional modules. The WBC series comes with a **30-year product warranty and linear power warranty**, placing it among the most durable solutions on the market. It is a proposition aimed at premium investors and installers who expect a combination of high efficiency, aesthetics, and long-term reliability in a single module. ## Notable figures - Efficiency of 24.7% matches the \*\*Back Contact 500-550W\*\* median - Power density of 247.4 W/m² matches the \*\*Back Contact 500-550W\*\* median - At -0.26%/°C, hot weather performance is typical for \*\*Back Contact 500-550W\*\* panels - Weight of 25.0 kg is 1.5 kg above \*\*Back Contact 500-550W\*\* median (23.5 kg) - verify structural support - Bifaciality factor of 75% can add 4-11% extra yield with reflective mounting surface ## Questions ### What is Back Contact technology in WINAICO WBC panels and how does it differ from standard modules? In Back Contact technology, all electrical contacts of the cells are moved to the rear side of the panel, so the front surface has no visible metal grid lines or busbars. In conventional modules, front-side busbars and finger lines shade part of the cell surface and limit energy yield. Eliminating these elements in WBC reduces optical and resistive losses, increasing actual energy output from the same mounting area. ### Do WINAICO WBC bifacial panels actually produce more energy? Yes, the bifacial glass-glass construction allows the WBC panel to capture light reflected from the ground, roof, or a light-colored facade, not just direct sunlight hitting the front. In practice this means additional energy gain, especially when installed over light-colored surfaces, ground-mounted systems, or facades, where reflected light matters more than on a typical pitched roof. ### What is the maximum power output of the WINAICO WBC panel and who is it designed for? WBC series modules reach up to 505 Wp thanks to monocrystalline n-type half-cells. This high unit power combined with the clean, uniformly black surface free of visible wiring makes the panels especially appealing for projects where roof or facade design matters as much as energy efficiency, such as premium buildings or commercial properties. ### What warranty comes with WINAICO WBC panels, and is it competitive? The WBC series carries a 30-year product warranty and a 30-year linear power warranty. This is significantly longer than the industry standard of around 10-12 years for product warranties and 25 years for power warranties offered by most manufacturers. This extended coverage places WBC among the most durable solutions on the market and reflects the manufacturer's confidence in its back-contact cells and glass-glass construction. ### Do WINAICO WBC panels handle partial shading well, for example from chimneys or trees? Yes, the bypass diodes built into WBC panels reduce the power losses that occur in conventional modules when part of the panel is shaded, for instance by a chimney, antenna, or tree branches. This prevents the entire cell string from being blocked by the shaded section, helping maintain higher energy production even under variable sunlight conditions throughout the day. ### Is WINAICO a reliable manufacturer, and where are WBC series panels produced? WINAICO is a tier 1 manufacturer headquartered in Taiwan with a long track record in the premium PV module market. Tier 1 status means the company appears on the list of the most bankable PV manufacturers, which simplifies project financing and increases confidence in the warranty provider's long-term financial stability. This is a key factor for investors and installers seeking long-term reliability, particularly given the 30-year warranty. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/WINAICO_WST-505BKX54-A3_AUS_CEC_1028_2026-06f822eb7246.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Jinko Solar JKM510T-48HL6M-DB](https://comparepv.com/panel/jinko-solar-jkm510t-48hl6m-db) | 510 W | Cooler, lighter, +0.8 pp | | [Jinko Solar JKM505T-48HL6M-DB](https://comparepv.com/panel/jinko-solar-jkm505t-48hl6m-db) | 505 W | Cooler, lighter, +0.6 pp | | [Jinko Solar JKM500T-48HL6M-DB](https://comparepv.com/panel/jinko-solar-jkm500t-48hl6m-db) | 500 W | Cooler, lighter, +0.3 pp | | [Longi Solar LR7-54HJD-510M](https://comparepv.com/panel/longi-lr7-54hjd-510m) | 510 W | Cooler, lighter, +0.3 pp | | [AIKO AIKO-A495-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a495-mce54mw) | 495 W | -10 W, lighter | | [Jinko Solar JKM495T-48HL6M-DB](https://comparepv.com/panel/jinko-solar-jkm495t-48hl6m-db) | 495 W | -10 W, cooler, lighter | | [Longi Solar LR7-54HJD-505M](https://comparepv.com/panel/longi-lr7-54hjd-505m) | 505 W | Cooler, lighter | | [Maxeon SPR-BE54-HD505](https://comparepv.com/panel/maxeon-spr-be54-hd505) | 505 W | Heavier, +10 yr warranty | | [WINAICO WST-475BDX54-A2](https://comparepv.com/panel/winaico-wst-475bdx54-a2) | 475 W | -30 W, -1.4 pp | | [WINAICO WST-480BDX54-B2](https://comparepv.com/panel/winaico-wst-480bdx54-b2) | 480 W | -25 W, -1.2 pp | | [WINAICO WST-485BDX54-A2](https://comparepv.com/panel/winaico-wst-485bdx54-a2) | 485 W | -20 W, -0.9 pp | | [WINAICO WST-490BDX54-A2](https://comparepv.com/panel/winaico-wst-490bdx54-a2) | 490 W | -15 W, -0.7 pp | | [WINAICO WST-495BKX54-B2](https://comparepv.com/panel/winaico-wst-495bkx54-b2) | 495 W | -10 W, -0.4 pp | --- Source: https://comparepv.com/panel/winaico-wst-505bkx54-a3 Not in this file, on the page: the I-V and temperature curves lifted from the manufacturer's datasheet, a thirty-year output simulator, a bifacial gain calculator and alternatives filtered by how closely they match these dimensions.