--- title: "Silfab SIL-620 XL 620W Solar Panel - Specs & Review | ComparePV" description: "Silfab SIL-620 XL 620W solar panel. Specs: 22.20% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/silfab-sil-620-xl" updated: 2026-09-11 --- # Silfab SIL-620 XL Light for its output, modest efficiency 359 panels in the segment N-type 600-650 W ## Identity - **Manufacturer:** Silfab - **Model:** SIL-620 XL - **Series:** NTC SIL-620/630/640 XL Bifacial - **Rated power:** 620 W - **Cell technology:** N-type - **Bifacial:** yes ## How it compares Compared against segment N-type 600-650 W (359 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 620 W | 625 W | Typical | | | Module efficiency | 22.20% | 22.77% | Weak - bottom 16% | 5,817 | | Power density | 222.0 | 227.7 | Weak - bottom 16% | 5,849 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,165 | | Weight (kg) | 29.5 kg | 32.5 kg | Strong - top 20% | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 22.20% | 22.77% | Weak - bottom 16% | 5,817 | | Power density | 222.0 | 227.7 | Weak - bottom 16% | 5,849 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,165 | | Weight per kWp | 47.6 | 52.7 | Strong - top 20% | 1,761 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Strengths - **47.6 kg per kWp** - Top 20% of the N-type 600-650 W segment, against a median of 52.7. ### Watch out for - **22.20% module efficiency** - Bottom 16% of the N-type 600-650 W segment, against a median of 22.77%. - **222.0 watts per square metre** - Bottom 16% of the N-type 600-650 W segment, against a median of 227.7. - **Best for:** Utility-scale and shaded-installations. - **Not ideal for:** Tight roof space and roofs where every square metre has to count. ## Specification ### Electrical - **Rated power (Pmax):** 620 W - **Efficiency:** 22.20 % - **Voltage at Pmax (Vmp):** 48.16 V - **Current at Pmax (Imp):** 12.87 A - **Open-circuit voltage (Voc):** 57.21 V - **Short-circuit current (Isc):** 13.55 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.290 %/degC - **Temperature coefficient of Voc:** -0.240 %/degC - **Temperature coefficient of Isc:** 0.040 %/degC - **NOCT:** 45 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** N-type - **Cell count:** 156 - **Bifacial:** yes ### Physical - **Length:** 2465 mm - **Width:** 1133 mm - **Thickness:** 35 mm - **Weight:** 29.5 kg - **Area:** 2.79 m2 - **Power density:** 222.0 Wp/m2 ### Warranty and degradation - **Product warranty:** 25 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 89.3 % - **First-year degradation:** 2.00 % - **Annual degradation:** 0.30 % - **Output after 30 years:** 554 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 5817 of 14005 | | Power density | 5849 of 14005 | | Temperature coefficient | 2165 of 14005 | | Weight | 1761 of 14005 | | Warranty | 21 of 14005 | ## About this series The SIL-620/630/640 XL Bifacial series is a lineup of utility-scale modules built for large solar farms where every percentage point of energy yield per hectare matters. The panels are based on **N-type cells with NTC technology**, whose rear passivation layer reduces charge carrier recombination, delivering higher and more stable performance over time compared to older P-type designs. The use of **half-cut cells** lowers module operating temperature and minimizes losses caused by shading, which is critical for large installations with uneven irradiance. The dual-sided, **bifacial construction** captures additional light reflected off the ground, increasing total energy yield without expanding the installation footprint. The panels are manufactured entirely in USA-based factories, which matters for projects subject to local content requirements and Buy American incentive programs. The series also stands out for its **high resistance to hail and harsh weather conditions** and is backed by one of the industry's longest warranties, 25 years on the product and 30 years on linear power degradation. This is a solution built for investors and EPCs delivering large-scale projects where low LCOE and long-term investment predictability are the top priorities. ## Notable figures - Module efficiency of 22.2% is 0.6pp below average for \*\*N-type 600-650W\*\* panels (median: 22.8%) - 222.0 W/m² power density is 5.7 W/m² below \*\*N-type 600-650W\*\* median (227.7 W/m²) - requires larger installation area - Temperature coefficient of -0.29%/°C matches the \*\*N-type 600-650W\*\* median - At 29.5 kg, this panel is 3.0 kg lighter than \*\*N-type 600-650W\*\* median (32.5 kg) - easier handling during installation - 80% bifaciality enables rear-side power generation, boosting yield by 4-12% on reflective surfaces ## Questions ### How do the N-type NTC cells in the Silfab SIL-620/630/640 XL panels differ from older P-type panels? N-type NTC cells feature a rear-side passivation layer that reduces carrier recombination. In practice, this delivers higher efficiency (up to about 23%), lower initial degradation, and more stable energy output over the module's lifetime compared to conventional P-type panels. ### How much extra energy does the bifacial design of the Silfab XL Bifacial panels really provide? The bifacial SIL-620/630/640 XL modules capture additional reflected light on the rear side of the panel. Silfab states that with a highly reflective surface, such as white gravel, rear-side gain can reach up to 90% of nominal power under favorable conditions, though typical utility-scale installations see a more modest single- to low-double-digit percentage boost, without increasing the plant's footprint. ### What is the maximum power and efficiency of the Silfab SIL-620/630/640 XL Bifacial modules? The series ranges from 620 W to 640 Wp, with efficiency reaching close to 23%. The panel measures 2465 x 1133 x 35 mm and weighs about 29.5 kg. The high per-module wattage reduces the number of panels needed to hit a target array capacity, lowering racking and wiring costs on large-scale projects. ### What warranty comes with the Silfab NTC XL Bifacial panels, and what does it cover? Silfab backs the series with a 25-year product warranty and a 30-year linear power warranty. This guarantees a slow, predictable degradation rate year over year, avoiding the step-down losses common in older technologies. For investors and EPCs running utility-scale projects, this is among the longest warranties on the market, simplifying LCOE modeling over multi-decade horizons. ### Are the Silfab XL Bifacial panels made in the USA, and does that matter for Buy American programs? Yes, the SIL-620/630/640 XL Bifacial modules are fully manufactured in Silfab's US factories. This is directly relevant to projects subject to domestic content requirements and Buy American-type incentive programs, including Inflation Reduction Act provisions where component origin affects eligibility for tax credits. ### Does the half-cut cell technology in the Silfab XL Bifacial panels actually reduce shading losses? Yes. Splitting cells into half-cuts lowers the current flowing through each section of the module, reducing power loss from partial shading, for example from passing clouds or soiling across a large array. The design also lowers the module's operating temperature, boosting efficiency on hot, sunny days. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/Silfab-SIL-620-630-640-XL-Bifacial-Data-Final-2ccf3061b85f.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A650-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a650-mae72mw) | 650 W | +30 W, cooler, +3.0 pp | | [AIKO AIKO-A645-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a645-mae72mw) | 645 W | +25 W, cooler, +2.8 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | +50 W, cooler, +2.6 pp | | [Longi Solar LR7-72HVHF-670M](https://comparepv.com/panel/longi-lr7-72hvhf-670m) | 670 W | +50 W, cooler, +2.6 pp | | [AIKO AIKO-A640-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a640-mae72mw) | 640 W | Cooler, lighter, +2.6 pp | | [Jinko Solar JKM650-670N-66QL6-BDV (670W class)](https://comparepv.com/panel/jinko-solar-jkm650-670n-66ql6-bdv-670w-class) | 670 W | +50 W, heavier, +2.6 pp | | [Silfab SIL-630 XL](https://comparepv.com/panel/silfab-sil-630-xl) | 630 W | +10 W, +0.4 pp | | [Silfab SIL-640 XL](https://comparepv.com/panel/silfab-sil-640-xl) | 640 W | +20 W, +0.7 pp | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | +60 W, cooler, +3.0 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | +55 W, cooler, +2.8 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | +80 W, heavier, +2.8 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | +75 W, heavier, +2.7 pp | --- Source: https://comparepv.com/panel/silfab-sil-620-xl Not in this file, on the page: a thirty-year output simulator, a bifacial gain calculator and alternatives filtered by how closely they match these dimensions.