--- title: "WINAICO WST-665BKX72-A2 Solar Panel: Specs & Datasheet | ComparePV" description: "WINAICO WST-665BKX72-A2 solar panel. Specs: 24.60% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/winaico-wst-665bkx72-a2" image: "https://comparepv.com/og/panel/winaico-wst-665bkx72-a2.png" updated: 2026-10-23 --- # WINAICO WST-665BKX72-A2 Solid all-round for its segment 88 panels in the segment Back Contact 650-700 W ## Identity - **Manufacturer:** WINAICO - **Model:** WST-665BKX72-A2 - **Series:** WST-BKX72-A2 WBC Series - **Rated power:** 665 W - **Cell technology:** Back Contact - **Bifacial:** yes ## How it compares Compared against segment Back Contact 650-700 W (88 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 665 W | 660 W | Typical | | | Module efficiency | 24.60% | 24.40% | Typical | 58 | | Power density | 246.2 | 244.3 | Typical | 47 | | Temperature coefficient | -0.260 | -0.260 | Typical | 515 | | Weight (kg) | 32.1 kg | 32.8 kg | Typical | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 24.60% | 24.40% | Typical | 58 | | Power density | 246.2 | 244.3 | Typical | 47 | | Temperature coefficient | -0.260 | -0.260 | Typical | 515 | | Weight per kWp | 48.3 | 49.8 | Typical | 2,141 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | - **Best for:** Utility-scale and commercial. ## Specification ### Electrical - **Rated power (Pmax):** 665 W - **Efficiency:** 24.60 % - **Voltage at Pmax (Vmp):** 45.60 V - **Current at Pmax (Imp):** 14.59 A - **Open-circuit voltage (Voc):** 54.30 V - **Short-circuit current (Isc):** 15.55 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:** 144 - **Bifacial:** yes - **Bifacial gain:** 20.00 ### Physical - **Length:** 2382 mm - **Width:** 1134 mm - **Thickness:** 30 mm - **Weight:** 32.1 kg - **Area:** 2.70 m2 - **Power density:** 246.2 Wp/m2 ### Warranty and degradation - **Product warranty:** 15 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:** 591 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 58 of 14129 | | Power density | 47 of 14129 | | Temperature coefficient | 515 of 14129 | | Weight | 2141 of 14129 | | Warranty | 21 of 14129 | ## About this series The WST-BKX72-A2 WBC Back Contact series is WINAICO's flagship utility-class solution, engineered for large-scale ground-mount installations and solar farms where every watt per square meter matters. The modules use **back contact technology** with N-type monocrystalline cells, meaning the front side of the module has no visible busbars or metallization grid - resulting in a cleaner appearance and reduced optical losses. An additional advantage is the **bifacial** glass-glass construction, which captures extra energy from reflected light hitting the rear side of the panel, meaningfully lowering the cost of energy in terms of LCOE. The series also stands out for its **high module efficiency** reaching 25%, which means fewer panels are needed to hit a target system capacity and lower BoS costs. Investors will appreciate the **low power degradation** in the first year and throughout subsequent years of operation, backed by a long-term product warranty and a linear performance guarantee. This makes it a strong choice for developers of commercial and industrial projects who demand high reliability, durability, and maximum return on investment from every square meter of roof or land. ## Notable figures - At 24.6% efficiency, this panel is on par with typical \*\*Back Contact 650-700W\*\* modules - At 246.2 W/m² power density, roof space requirements are typical for \*\*Back Contact 650-700W\*\* panels - At -0.26%/°C, hot weather performance is typical for \*\*Back Contact 650-700W\*\* panels - 40% bifaciality enables rear-side power generation, boosting yield by 2-6% on reflective surfaces - #58 for efficiency, #515 for temperature performance out of 14129 panels ## Questions ### What is back contact technology in the WINAICO WST-BKX72-A2 panels and how does it differ from conventional panels? Back contact means all cell interconnections, including busbars, are placed on the rear side of the module instead of the front, as in conventional panels. This gives the front surface a uniform black appearance without visible metallization grids, reducing optical losses and improving aesthetics. In practice, this results in higher energy conversion efficiency compared to traditional PERC monocrystalline cells. ### Do WST-BKX72-A2 WBC bifacial panels actually produce extra energy in real conditions? Yes, the glass-glass construction allows the panel to capture light reflected off the ground on its rear side as well, yielding an additional energy gain of several to over a dozen percent depending on ground albedo and mounting height. In ground-mounted installations with light-colored surfaces, such as gravel or white membrane, the bifacial effect is especially noticeable and meaningfully lowers the cost of energy measured as LCOE. ### What is the maximum power output of the WST-BKX72-A2 WBC series, and how many panels are needed for a typical utility-scale PV plant? The flagship model in this series reaches a maximum power output of 675 Wp with a module efficiency of up to 25 percent. This high per-unit power means fewer panels are required to reach a given installed capacity compared to lower-efficiency modules, which reduces mounting structure, cabling, and labor costs, known collectively as BoS costs. ### What warranty applies to the WINAICO WST-BKX72-A2 WBC panels, and is it reliable? The manufacturer provides a 15-year product warranty along with a 30-year linear performance warranty, which is above the market average. WINAICO is a Taiwan-based Tier 1 manufacturer with over a decade in the market, which increases confidence that warranty commitments will be honored throughout the system's operating life. ### Is the WST-BKX72-A2 WBC series better suited for large solar farms or residential rooftop installations? This series was designed for large ground-mounted installations and utility-scale solar farms rather than typical residential rooftop systems. Its larger module dimensions and high per-unit power rating of 675 Wp work best in commercial and industrial projects, where maximizing power output per square meter of land is the priority. ### Are WINAICO back contact panels more prone to microcracks or failures than conventional PERC panels? No, back contact technology does not increase the risk of microcracks or failures - on the contrary, the absence of front-side busbars combined with the glass-glass construction improves mechanical rigidity and durability. This design also better protects the cells from moisture and corrosion, supporting the low first-year power degradation and the low degradation rates seen in subsequent years of operation. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/WINAICO_WST-675BKX72-A2_AUS_CEC_0826-e5cd832f90ea.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A650-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a650-mae72mw) | 650 W | -15 W, lighter, +0.6 pp | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | +15 W, lighter, +0.6 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | +10 W, lighter, +0.4 pp | | [AIKO AIKO-A645-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a645-mae72mw) | 645 W | -20 W, lighter, +0.4 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | +35 W, heavier, +0.4 pp | | [WINAICO WST-675BKX72-A2](https://comparepv.com/panel/winaico-wst-675bkx72-a2) | 675 W | +10 W, +0.4 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | +30 W, heavier, +0.3 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | Lighter | | [WINAICO WST-625NHX66-A4](https://comparepv.com/panel/winaico-wst-625nhx66-a4) | 625 W | -40 W, cooler, -1.5 pp | | [WINAICO WST-630NHX66-A4](https://comparepv.com/panel/winaico-wst-630nhx66-a4) | 630 W | -35 W, cooler, -1.3 pp | | [WINAICO WST-670BKX72-A2](https://comparepv.com/panel/winaico-wst-670bkx72-a2) | 670 W | Very close match | | [Longi Solar LR7-72HVHF-670M](https://comparepv.com/panel/longi-lr7-72hvhf-670m) | 670 W | Lighter | | [Jinko Solar JKM650-670N-66QL6-BDV (670W class)](https://comparepv.com/panel/jinko-solar-jkm650-670n-66ql6-bdv-670w-class) | 670 W | Very close match | --- Source: https://comparepv.com/panel/winaico-wst-665bkx72-a2 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.