--- title: "Waaree WSMD-645 645W Solar Panel - Specs & Review | ComparePV" description: "Waaree WSMD-645 645W solar panel. Specs: 20.65% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/waaree-wsmd-645" updated: 2026-09-11 --- # Waaree WSMD-645 Middle of its segment, modest efficiency 217 panels in the segment PERC 600-650 W ## Identity - **Manufacturer:** Waaree - **Model:** WSMD-645 - **Series:** ARKA SERIES - **Rated power:** 645 W - **Cell technology:** PERC ## How it compares Compared against segment PERC 600-650 W (217 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 645 W | 605 W | Strong - top 7% | | | Module efficiency | 20.65% | 21.38% | Weak - bottom 6% | 11,014 | | Power density | 206.4 | 213.8 | Weak - bottom 6% | 11,023 | | Temperature coefficient | -0.340 | -0.340 | Typical | 8,778 | | Weight (kg) | 34.5 kg | 34.0 kg | Typical | | | Performance warranty | 27 yrs | 30 yrs | Typical | 9,667 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 20.65% | 21.38% | Weak - bottom 6% | 11,014 | | Power density | 206.4 | 213.8 | Weak - bottom 6% | 11,023 | | Temperature coefficient | -0.340 | -0.340 | Typical | 8,778 | | Weight per kWp | 53.5 | 55.7 | Typical | 7,451 | | Performance warranty | 27 yrs | 30 yrs | Typical | 9,667 | ### Watch out for - **20.65% module efficiency** - Bottom 6% of the PERC 600-650 W segment, against a median of 21.38%. Ranked 11,014th in the whole database. - **206.4 watts per square metre** - Bottom 6% of the PERC 600-650 W segment, against a median of 213.8. Ranked 11,023rd in the whole database. - **Best for:** Residential, 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):** 645 W - **Efficiency:** 20.65 % - **Voltage at Pmax (Vmp):** 37.87 V - **Current at Pmax (Imp):** 17.04 A - **Open-circuit voltage (Voc):** 45.94 V - **Short-circuit current (Isc):** 17.78 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.340 %/degC - **Temperature coefficient of Voc:** -0.250 %/degC - **Temperature coefficient of Isc:** 0.040 %/degC - **NOCT:** 43 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** PERC - **Cell count:** 132 ### Physical - **Length:** 2400 mm - **Width:** 1302 mm - **Thickness:** 35 mm - **Weight:** 34.5 kg - **Area:** 3.12 m2 - **Power density:** 206.4 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 27 years - **Output guaranteed at end of warranty:** 83.7 % - **First-year degradation:** 2.00 % - **Annual degradation:** 0.55 % - **Output after 30 years:** 529 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 11014 of 14005 | | Power density | 11023 of 14005 | | Temperature coefficient | 8778 of 14005 | | Weight | 7451 of 14005 | | Warranty | 9667 of 14005 | ## About this series The Waaree ARKA SERIES was designed for high energy production while maintaining stable performance on real rooftop or farm installations-especially when partial shading, dirt accumulation, or high temperatures occur. The use of **monocrystalline Mono PERC cells** in a **half-cut** configuration helps reduce losses and improve yield when the installation does not have ideal sunlight exposure throughout the day. Another distinguishing feature is the **multi-busbar structure**, optimized for better current conduction and higher resistance to micro-cracking, which is crucial during transportation and long-term operation. In practice, ARKA SERIES addresses typical challenges faced by investors in Poland: yield drops during hot weather, sensitivity to shading, and the risk of degradation in demanding environments. This is achieved thanks to **PID resistance** and carefully processed lamination materials as well as housing connection box protection. This is a good choice for premium residential installations, commercial rooftops, and larger systems where **reliable performance and durability** matter more than catalog parameters. ## Notable figures - Module efficiency of 20.6% is 0.7pp below average for \*\*PERC 600-650W\*\* panels (median: 21.4%) - Power density of 206.4 W/m² is 7.4 W/m² below \*\*PERC 600-650W\*\* median (213.8 W/m²) - needs more roof space - At -0.34%/°C, hot weather performance is typical for \*\*PERC 600-650W\*\* panels - #11014 for efficiency, #8778 for temperature performance out of 14005 panels ## Questions ### How much power do Waaree ARKA SERIES panels deliver and what installations are they suited for? ARKA SERIES panels reach up to 665 Wp, meaning fewer modules are needed to reach a given system size compared to conventional 400-450 Wp panels. This reduces the number of mounting components and shortens installation time. They work well for premium residential systems, commercial rooftops, and larger PV farms where maximizing yield from limited roof area matters. ### What's the difference between half-cut and multi-busbar technology in ARKA SERIES versus standard monocrystalline panels? The Mono PERC cells in ARKA SERIES are cut in half, reducing current losses and limiting the impact of partial shading - if only part of the panel is shaded, the rest keeps working more efficiently than in a full-cell panel. The multi-busbar design further improves current conduction between cells and increases resistance to microcracks that can occur during transport or over years of roof exposure. ### How do ARKA SERIES panels perform in summer heat on the roof? High roof temperatures typically reduce output in conventional panels, but the Mono PERC half-cut cell design in ARKA SERIES limits these losses through better heat distribution and lower internal resistance. In practice this means more stable energy production on hot days compared to older-generation, cheaper panels - an important factor when designing systems for both pitched residential roofs and flat commercial roofs. ### What warranty comes with Waaree ARKA SERIES panels? Waaree, a Tier 1 manufacturer, provides a 12-year product warranty and a 27-year power output warranty. This means the module should maintain its guaranteed output level as specified in the datasheet for 27 years, while the manufacturer covers repair or replacement for material or workmanship defects during the first 12 years. ### Are ARKA SERIES panels PID-resistant and suitable for demanding conditions like high humidity or dust? Yes, ARKA SERIES modules carry certified PID (potential-induced degradation) resistance, preventing gradual power loss under high system voltage and humidity. Refined lamination and a sealed junction box further protect the panel from moisture and contamination, which matters both on residential roofs and in farm-scale installations exposed to dust or pollen. ### Are Waaree ARKA SERIES panels bifacial, generating power from the rear side? No, the PERC-cell ARKA SERIES modules are monofacial, not bifacial. All energy is generated solely from the front side facing the sun. If you want extra yield from reflected light off the ground, look at Waaree's separately labeled bifacial variants, which use a transparent rear layer instead of a standard backsheet. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/ARKA-SERIES-WSMD-645-665-WEL-E-PD-645-665-132-MP-HC-06-17-11-1d670518a4b4.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A650-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a650-mae72mw) | 650 W | Cooler, lighter, +4.6 pp | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | Cooler, lighter, +4.6 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | Cooler, lighter, +4.4 pp | | [AIKO AIKO-A645-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a645-mae72mw) | 645 W | Cooler, lighter, +4.4 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | +50 W, cooler, +4.2 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | Cooler, lighter, +4.2 pp | | [Longi Solar LR7-72HVHF-670M](https://comparepv.com/panel/longi-lr7-72hvhf-670m) | 670 W | Cooler, lighter, +4.2 pp | | [Waaree WSMD-650](https://comparepv.com/panel/waaree-wsmd-650) | 650 W | Very close match | | [Waaree WSMD-655](https://comparepv.com/panel/waaree-wsmd-655) | 655 W | +10 W, +0.3 pp | | [Waaree WSMD-660](https://comparepv.com/panel/waaree-wsmd-660) | 660 W | +15 W, +0.5 pp | | [Waaree Bi-68-665](https://comparepv.com/panel/waaree-bi-68-665) | 665 W | Heavier, +0.6 pp, +3 yr warranty | | [AIKO AIKO-A805-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a805-grh78dw) | 805 W | +160 W, cooler, +4.5 pp | | [AIKO AIKO-A800-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a800-grh78dw) | 800 W | +155 W, cooler, +4.2 pp | | [AIKO AIKO-A795-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a795-grh78dw) | 795 W | +150 W, cooler, +4.2 pp | | [AIKO AIKO-A790-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a790-grh78dw) | 790 W | +145 W, cooler, +4.0 pp | | [Trina Solar TSM-NEG21C.20Q-760](https://comparepv.com/panel/trina-solar-tsm-neg21c-20q-760) | 760 W | +115 W, cooler, +3.9 pp | --- Source: https://comparepv.com/panel/waaree-wsmd-645 Not in this file, on the page: a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.