--- title: "S-Energy SL65-66MAJ-505Z 505W Solar Panel - Specs & Review | ComparePV" description: "S-Energy SL65-66MAJ-505Z 505W solar panel. Specs: 21.21% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/s-energy-sl65-66maj-505z" updated: 2026-09-11 --- # S-Energy SL65-66MAJ-505Z Space saver, short guarantee 706 panels in the segment PERC 500-550 W ## Identity - **Manufacturer:** S-Energy - **Model:** SL65-66MAJ-505Z - **Series:** SL65-66MAJ - **Rated power:** 505 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) | 505 W | 535 W | Weak - bottom 11% | | | Module efficiency | 21.21% | 20.90% | Strong - top 8% | 9,075 | | Power density | 212.1 | 209.0 | Strong - top 8% | 9,089 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,419 | | Weight (kg) | 27.0 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 | 21.21% | 20.90% | Strong - top 8% | 9,075 | | Power density | 212.1 | 209.0 | Strong - top 8% | 9,089 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,419 | | Weight per kWp | 53.5 | 53.0 | Typical | 7,409 | | Performance warranty | 25 yrs | 30 yrs | Weak - bottom 23% | 9,798 | ### Strengths - **212.1 watts per square metre** - Top 8% of the PERC 500-550 W segment, against a median of 209.0. Ranked 9,089th in the whole database. - **21.21% module efficiency** - Top 8% of the PERC 500-550 W segment, against a median of 20.90%. Ranked 9,075th in the whole database. ### 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):** 505 W - **Efficiency:** 21.21 % - **Voltage at Pmax (Vmp):** 38.30 V - **Current at Pmax (Imp):** 13.19 A - **Open-circuit voltage (Voc):** 45.90 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:** -0.290 %/degC - **Temperature coefficient of Isc:** 0.050 %/degC - **NOCT:** 44 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** PERC - **Cell count:** 66 ### Physical - **Length:** 2100 mm - **Width:** 1134 mm - **Thickness:** 35 mm - **Weight:** 27.0 kg - **Area:** 2.38 m2 - **Power density:** 212.1 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 25 years - **Output guaranteed at end of warranty:** 84.8 % - **First-year degradation:** 2.00 % - **Annual degradation:** 0.55 % - **Output after 30 years:** 414 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 9075 of 14005 | | Power density | 9089 of 14005 | | Temperature coefficient | 10419 of 14005 | | Weight | 7409 of 14005 | | Warranty | 9798 of 14005 | ## About this series The S-Energy SL65-66MAJ series is designed for installations where stable performance under varying conditions - from full sun to partial shading - is crucial. The use of **monocrystalline cells in a half-cut configuration** minimizes losses due to heating and improves performance when the roof is intermittently shaded by chimneys, skylights, or trees. The modules utilize a **132-cell architecture**, which translates to a better distribution of current loads and greater resistance to micro-cracks during transport and installation. In practice, the SL65-66MAJ addresses a common problem for investors in Poland - decreased production in hot weather and uneven performance of strings under partial shading - thanks to its **favorable temperature characteristics** and well-thought-out electrical design. It is a good choice for single-family homes, businesses, and larger roofs where quick project completion and predictable performance over many years are important. An additional advantage is its **conservative power tolerance** and carefully considered safety features (including a sealed connection box), which facilitate long-term operation. ## Notable figures - At 21.2% efficiency, this panel is on par with typical \*\*PERC 500-550W\*\* modules - Power density of 212.1 W/m² packs 3.1 W/m² more into the same footprint vs \*\*PERC 500-550W\*\* median (209.0 W/m²) - Temperature coefficient of -0.35%/°C matches the \*\*PERC 500-550W\*\* median - Weight of 27.0 kg (1.4 kg below \*\*PERC 500-550W\*\* median of 28.4 kg) allows easier transport and roof mounting - In the top 65% for efficiency among all PERC panels ## Questions ### What warranty does the S-Energy SL65-66MAJ series come with? The SL65-66MAJ series carries a 12-year product warranty covering material and workmanship defects. S-Energy also provides a 25-year linear power output warranty, guaranteeing that modules retain at least 80% of their rated power after that period. This is standard coverage for panels in this category. Before signing a contract, verify that the local distributor offers after-sales support in your country. ### Does the half-cut PERC technology in the SL65-66MAJ actually improve performance under shading? Yes. Half-cut cells are split in half, so a shadow covering part of the module blocks a smaller share of its output than in conventional full-cell panels. The 132-cell layout in the SL65-66MAJ limits losses from shading caused by chimneys, dormers, or trees, resulting in measurably higher annual energy yield, especially on roofs with complex geometry. ### How do the S-Energy SL65-66MAJ panels perform in hot weather? The power temperature coefficient is approximately -0.35%/°C, meaning the modules lose slightly less output during extreme heat compared to older full-cell designs. This favorable temperature characteristic translates into better production on summer afternoons in Central Europe, when module surface temperatures can exceed 65°C. ### How many S-Energy SL65-66MAJ panels are needed for a 10 kWp system? At 505 Wp per module, a 10 kWp system requires approximately 20 panels. For a typical single-family home consuming 4-6 MWh per year, 10-14 modules (5-7 kWp) are usually sufficient. The exact count is determined by a designer after analyzing actual electricity consumption and available roof area. ### Who manufactures S-Energy panels and are they a reputable brand? S-Energy is a South Korean solar panel manufacturer founded in 2001, originating from Samsung's photovoltaic division, with its own production facilities in South Korea. According to available data, the company is not currently listed as a Bloomberg NEF Tier 1 manufacturer, though its modules meet IEC standards and have been present on European markets for years. Confirm warranty support terms with the local distributor before purchasing. ### Are the SL65-66MAJ modules compatible with popular inverters available on the market? Yes. The SL65-66MAJ series meets electrical standards enabling compatibility with inverters from leading brands such as SMA, Fronius, Huawei, and Growatt, supporting system voltages up to 1000 or 1500 V DC. Before purchasing, have your installer verify that the inverter's MPPT input ranges match the current and voltage parameters of this series. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/half-sl65-66maj-480-505z-220308-2022-en-ver-1-0-186da3891bc7.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Longi Solar LR7-54HJD-510M](https://comparepv.com/panel/longi-lr7-54hjd-510m) | 510 W | Cooler, +3.8 pp, +5 yr warranty | | [AIKO AIKO-A495-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a495-mce54mw) | 495 W | Cooler, lighter, +3.6 pp | | [Longi Solar LR7-54HJD-505M](https://comparepv.com/panel/longi-lr7-54hjd-505m) | 505 W | Cooler, +3.5 pp, +5 yr warranty | | [Longi Solar LR7-60HVH-555M](https://comparepv.com/panel/longi-lr7-60hvh-555m) | 555 W | +50 W, cooler, +3.4 pp | | [AIKO AIKO-A490-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a490-mce54mw) | 490 W | Cooler, lighter, +3.3 pp | | [Longi Solar LR7-54HJD-500M](https://comparepv.com/panel/longi-lr7-54hjd-500m) | 500 W | Cooler, +3.3 pp, +5 yr warranty | | [S-Energy SL65-66BDJ-480Z](https://comparepv.com/panel/s-energy-sl65-66bdj-480z) | 480 W | -25 W, -1.0 pp, +5 yr warranty | | [S-Energy SL65-66MAJ-480Z](https://comparepv.com/panel/s-energy-sl65-66maj-480z) | 480 W | -25 W, -1.1 pp | | [S-Energy SL65-66BDJ-485Z](https://comparepv.com/panel/s-energy-sl65-66bdj-485z) | 485 W | -20 W, -0.8 pp, +5 yr warranty | | [S-Energy SL65-66MAJ-485Z](https://comparepv.com/panel/s-energy-sl65-66maj-485z) | 485 W | -20 W, -0.8 pp | | [S-Energy SL65-66BAJ-490S](https://comparepv.com/panel/s-energy-sl65-66baj-490s) | 490 W | -15 W, -0.5 pp | | [S-Energy SL65-66BDJ-490Z](https://comparepv.com/panel/s-energy-sl65-66bdj-490z) | 490 W | Heavier, -0.6 pp, +5 yr warranty | | [S-Energy SL65-66MAJ-490Z](https://comparepv.com/panel/s-energy-sl65-66maj-490z) | 490 W | -15 W, -0.6 pp | | [S-Energy SL65-66BAJ-495S](https://comparepv.com/panel/s-energy-sl65-66baj-495s) | 495 W | -10 W, -0.3 pp | | [S-Energy SL65-66BDJ-495Z](https://comparepv.com/panel/s-energy-sl65-66bdj-495z) | 495 W | Heavier, -0.4 pp, +5 yr warranty | | [S-Energy SL65-66MAJ-495Z](https://comparepv.com/panel/s-energy-sl65-66maj-495z) | 495 W | -10 W, -0.4 pp | | [Gamko New Energy GKA120N-PRO-590W](https://comparepv.com/panel/gamko-new-energy-gka120n-pro-590w) | 590 W | +85 W, +2.6 pp, +5 yr warranty | --- Source: https://comparepv.com/panel/s-energy-sl65-66maj-505z Not in this file, on the page: a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.