--- title: "S-Energy SL65-66BAJ-500S 500W Solar Panel - Specs & Review | ComparePV" description: "S-Energy SL65-66BAJ-500S 500W solar panel. Specs: 21.10% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/s-energy-sl65-66baj-500s" updated: 2026-09-11 --- # S-Energy SL65-66BAJ-500S Efficiency leader, short guarantee 706 panels in the segment PERC 500-550 W ## Identity - **Manufacturer:** S-Energy - **Model:** SL65-66BAJ-500S - **Series:** SL65-66BAJ - **Rated power:** 500 W - **Cell technology:** PERC ## How it compares Compared against segment PERC 500-550 W (706 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 500 W | 535 W | Weak - bottom 4% | | | Module efficiency | 21.10% | 20.90% | Strong - top 20% | 9,297 | | Power density | 211.0 | 209.0 | Strong - top 23% | 9,398 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,419 | | Weight (kg) | 26.5 kg | 28.4 kg | Typical | | | Performance warranty | 25 yrs | 30 yrs | Weak - bottom 23% | 9,798 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 21.10% | 20.90% | Strong - top 20% | 9,297 | | Power density | 211.0 | 209.0 | Strong - top 23% | 9,398 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,419 | | Weight per kWp | 53.0 | 53.0 | Typical | 6,725 | | Performance warranty | 25 yrs | 30 yrs | Weak - bottom 23% | 9,798 | ### Strengths - **21.10% module efficiency** - Top 20% of the PERC 500-550 W segment, against a median of 20.90%. - **211.0 watts per square metre** - Top 23% of the PERC 500-550 W segment, against a median of 209.0. ### Watch out for - **25 year performance warranty** - Bottom 23% of the PERC 500-550 W segment, against a median of 30 yrs. - **Best for:** Residential, commercial and shaded-installations. - **Not ideal for:** Owners who want a long output guarantee. ## Specification ### Electrical - **Rated power (Pmax):** 500 W - **Efficiency:** 21.10 % - **Voltage at Pmax (Vmp):** 38.30 V - **Current at Pmax (Imp):** 13.06 A - **Open-circuit voltage (Voc):** 45.50 V - **Short-circuit current (Isc):** 13.90 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.350 %/degC - **Temperature coefficient of Voc:** -0.270 %/degC - **Temperature coefficient of Isc:** 0.040 %/degC - **NOCT:** 45 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** PERC - **Cell count:** 132 ### Physical - **Length:** 2090 mm - **Width:** 1134 mm - **Thickness:** 35 mm - **Weight:** 26.5 kg - **Area:** 2.37 m2 - **Power density:** 211.0 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 25 years - **Output guaranteed at end of warranty:** 85.0 % - **First-year degradation:** 2.00 % - **Annual degradation:** 0.54 % - **Output after 30 years:** 412 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 9297 of 14005 | | Power density | 9398 of 14005 | | Temperature coefficient | 10419 of 14005 | | Weight | 6725 of 14005 | | Warranty | 9798 of 14005 | ## About this series The S-Energy SL65-66BAJ series is designed to maximize energy output on a limited surface area - without compromising reliability. These are **monocrystalline** modules in a **132 half-cut cell** configuration, which are better suited to partial shading and minimize losses due to panel heating during operation. In practice, this means more stable production in typical Polish rooftop conditions - with chimneys, skylights, or installations spread across multiple roof sections. Another key feature of this series is its refined design, featuring **tempered glass with an anti-reflective coating**, which supports more effective light utilization on cloudy days and at low angles. The entire system is also completed by a **high-sealing connection (IP68)**, which is important for long-term operation in humid, snowy, and dusty conditions. The SL65-66BAJ is a good choice for residential and commercial installations where predictable performance, weather resistance, and high-quality construction are important - features often found in premium segments. ## Notable figures - Efficiency of 21.1% matches the \*\*PERC 500-550W\*\* median - Power density of 211.0 W/m² matches the \*\*PERC 500-550W\*\* median - At -0.35%/°C, hot weather performance is typical for \*\*PERC 500-550W\*\* panels - 26.5 kg weight - 1.9 kg lighter than \*\*PERC 500-550W\*\* median (28.4 kg), reducing installation effort - #9297 for efficiency, #10419 for temperature performance out of 14005 panels ## Questions ### What is the warranty on S-Energy SL65-66BAJ solar panels? The SL65-66BAJ series comes with a 12-year product warranty and a 25-year linear power output warranty. After 25 years of operation, the panel is guaranteed to retain at least 85% of its rated power. This is a standard premium-tier warranty level and provides a solid basis for long-term return-on-investment calculations. ### Are S-Energy SL65-66BAJ panels a good fit for roofs with chimneys or dormers? Yes, the SL65-66BAJ series is particularly well-suited for such installations. The 132-cell half-cut layout means partial shading from a chimney, dormer, or antenna affects only a fraction of the module, keeping energy losses significantly lower than on conventional full-cell panels. The manufacturer explicitly designed this series for the shading conditions typical of Polish residential rooftops. ### What is the peak power output of the SL65-66BAJ series and how many panels do I need for a home system? The top model in this series delivers 500 Wp of peak power. A typical residential system rated at 6–10 kW requires between 12 and 20 panels. The high per-module output means fewer panels and less roof area are needed to reach a given system size compared to older 350–400 Wp modules. ### Does the PERC cell technology in the SL65-66BAJ make a difference under Poland's often overcast skies? Yes. The monocrystalline PERC cells used in the SL65-66BAJ respond better to diffuse and low-intensity light than older standard cells. Combined with tempered glass and an anti-reflective coating, the panel captures more energy from low-angle sunlight and overcast conditions, resulting in a higher annual energy yield in a temperate climate. ### How do S-Energy SL65-66BAJ panels perform in high summer temperatures? The power temperature coefficient for this series is -0.35% per degree Celsius above 25°C. On a hot day when the panel surface reaches 65°C, output drops by roughly 14% relative to STC-rated power. The half-cut cell architecture further reduces thermal losses by splitting each cell into two independent halves, lowering internal resistance and improving performance under real-world high-temperature conditions. ### Is S-Energy a Tier 1 manufacturer and can I trust them for a long-term installation? S-Energy is a South Korean manufacturer with extensive industry experience, but it is not currently listed as a Tier 1 supplier by Bloomberg NEF. This does not indicate poor quality — many reliable brands outside that list deliver premium-grade products. Before purchasing, it is worth verifying the manufacturer's current financial stability and the availability of warranty service in your country, since honoring a 25-year power guarantee depends on the company remaining in operation. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/sl65-66baj-xxxs-230316-dbfb6317bfb8.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Longi Solar LR7-54HJD-510M](https://comparepv.com/panel/longi-lr7-54hjd-510m) | 510 W | Cooler, +3.9 pp, +5 yr warranty | | [AIKO AIKO-A495-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a495-mce54mw) | 495 W | Cooler, lighter, +3.7 pp | | [Longi Solar LR7-54HJD-505M](https://comparepv.com/panel/longi-lr7-54hjd-505m) | 505 W | Cooler, +3.6 pp, +5 yr warranty | | [AIKO AIKO-A490-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a490-mce54mw) | 490 W | Cooler, lighter, +3.4 pp | | [Longi Solar LR7-54HJD-500M](https://comparepv.com/panel/longi-lr7-54hjd-500m) | 500 W | Cooler, +3.4 pp, +5 yr warranty | | [Talesun CIPRO-TN9C54M-500W](https://comparepv.com/panel/talesun-cipro-tn9c54m-500w) | 500 W | Cooler, lighter, +3.4 pp | | [S-Energy SL65-66BDJ-480Z](https://comparepv.com/panel/s-energy-sl65-66bdj-480z) | 480 W | Heavier, -0.9 pp, +5 yr warranty | | [S-Energy SL65-66MAJ-480Z](https://comparepv.com/panel/s-energy-sl65-66maj-480z) | 480 W | -20 W, -0.9 pp | | [S-Energy SL65-66BDJ-485Z](https://comparepv.com/panel/s-energy-sl65-66bdj-485z) | 485 W | Heavier, -0.7 pp, +5 yr warranty | | [S-Energy SL65-66MAJ-485Z](https://comparepv.com/panel/s-energy-sl65-66maj-485z) | 485 W | -15 W, -0.7 pp | | [S-Energy SL65-66BAJ-490S](https://comparepv.com/panel/s-energy-sl65-66baj-490s) | 490 W | -10 W, -0.4 pp | | [S-Energy SL65-66BDJ-490Z](https://comparepv.com/panel/s-energy-sl65-66bdj-490z) | 490 W | Heavier, -0.5 pp, +5 yr warranty | | [S-Energy SL65-66MAJ-490Z](https://comparepv.com/panel/s-energy-sl65-66maj-490z) | 490 W | -10 W, -0.5 pp | | [S-Energy SL65-66BAJ-495S](https://comparepv.com/panel/s-energy-sl65-66baj-495s) | 495 W | -0.2 pp | | [S-Energy SL65-66BDJ-495Z](https://comparepv.com/panel/s-energy-sl65-66bdj-495z) | 495 W | Heavier, -0.2 pp, +5 yr warranty | | [S-Energy SL65-66MAJ-495Z](https://comparepv.com/panel/s-energy-sl65-66maj-495z) | 495 W | -0.3 pp | | [Longi Solar LR7-60HVH-560M](https://comparepv.com/panel/longi-lr7-60hvh-560m) | 560 W | +60 W, cooler, +3.7 pp | --- Source: https://comparepv.com/panel/s-energy-sl65-66baj-500s Not in this file, on the page: a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.