--- title: "S-Energy SL45-78BGI-475S 475W Solar Panel - Specs & Review | ComparePV" description: "S-Energy SL45-78BGI-475S 475W solar panel. Specs: 20.20% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/s-energy-sl45-78bgi-475s" updated: 2026-09-11 --- # S-Energy SL45-78BGI-475S Middle of its segment, modest efficiency 449 panels in the segment PERC 450-500 W ## Identity - **Manufacturer:** S-Energy - **Model:** SL45-78BGI-475S - **Series:** SL45-78BGI - **Rated power:** 475 W - **Cell technology:** PERC - **Bifacial:** yes ## How it compares Compared against segment PERC 450-500 W (449 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 475 W | 460 W | Typical | | | Module efficiency | 20.20% | 20.82% | Weak - bottom 5% | 11,956 | | Power density | 202.1 | 208.5 | Weak - bottom 5% | 11,985 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,419 | | Weight (kg) | 26.5 kg | 24.5 kg | Typical | | | Performance warranty | 25 yrs | 25 yrs | Typical | 9,798 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 20.20% | 20.82% | Weak - bottom 5% | 11,956 | | Power density | 202.1 | 208.5 | Weak - bottom 5% | 11,985 | | Temperature coefficient | -0.350 | -0.350 | Typical | 10,419 | | Weight per kWp | 55.8 | 53.1 | Typical | 10,163 | | Performance warranty | 25 yrs | 25 yrs | Typical | 9,798 | ### Watch out for - **20.20% module efficiency** - Bottom 5% of the PERC 450-500 W segment, against a median of 20.82%. Ranked 11,956th in the whole database. - **202.1 watts per square metre** - Bottom 5% of the PERC 450-500 W segment, against a median of 208.5. Ranked 11,985th in the whole database. - **Best for:** Commercial. - **Not ideal for:** Tight roof space and roofs where every square metre has to count. ## Specification ### Electrical - **Rated power (Pmax):** 475 W - **Efficiency:** 20.20 % - **Voltage at Pmax (Vmp):** 44.60 V - **Current at Pmax (Imp):** 10.65 A - **Open-circuit voltage (Voc):** 53.70 V - **Short-circuit current (Isc):** 11.29 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:** 156 - **Bifacial:** yes - **Bifacial gain:** 5.00 ### Physical - **Length:** 2264 mm - **Width:** 1038 mm - **Thickness:** 40 mm - **Weight:** 26.5 kg - **Area:** 2.35 m2 - **Power density:** 202.1 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:** 391 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 11956 of 14005 | | Power density | 11985 of 14005 | | Temperature coefficient | 10419 of 14005 | | Weight | 10163 of 14005 | | Warranty | 9798 of 14005 | ## About this series The S-Energy SL45-78BGI series are **bifacial** modules with monocrystalline solar cells, designed to effectively increase energy yield in locations where every extra percentage counts - on industrial rooftops, in commercial installations, and in PV farms. By utilizing both sides, the panel better captures reflected light from the ground, helping to minimize losses under less-than-ideal sunlight conditions and improving daily production. A key feature of the series is **positive power tolerance**, which simplifies precise project planning and minimizes the risk of "under-delivering" on parameters in larger investments. The durable design includes **tempered glass with an anti-reflective coating**, as well as robust construction for long-term outdoor use. For installers, **compatibility with 1500 V systems** is also important, allowing for optimized string configurations in large installations and reducing cabling costs. This is a proposition for investors seeking predictable yields, stable quality, and an advantage over standard monofacial modules. ## Notable figures - Module efficiency of 20.2% is 0.6pp below average for \*\*PERC 450-500W\*\* panels (median: 20.8%) - Power density of 202.1 W/m² is 6.4 W/m² below \*\*PERC 450-500W\*\* median (208.5 W/m²) - needs more roof space - Temperature coefficient of -0.35%/°C matches the \*\*PERC 450-500W\*\* median - At 26.5 kg, this panel is 2.0 kg heavier than the \*\*PERC 450-500W\*\* median (24.5 kg) - more demanding for installation crews - Ranked #11956 out of 14005 panels for efficiency in the database ## Questions ### Is the S-Energy SL45-78BGI series still available for purchase? The SL45-78BGI series has been discontinued and is no longer part of S-Energy's active product lineup. Some distributors may still hold remaining inventory, but availability is not guaranteed. Before purchasing, confirm current stock levels with your supplier and verify their ability to support warranty claims going forward. ### What warranty does S-Energy offer on the SL45-78BGI modules? S-Energy provides a 12-year product warranty covering material and workmanship defects, along with a 25-year linear power output warranty guaranteeing a defined minimum performance level. Keep in mind that since the series is discontinued, the manufacturer's long-term capacity to honor warranty claims may be a factor worth evaluating before committing to a large purchase. ### What is bifacial PERC technology and what does it mean for the SL45-78BGI? PERC (Passivated Emitter and Rear Cell) cells feature a rear passivation layer that improves photon capture. Combined with the bifacial design, the SL45-78BGI generates power from both direct sunlight and albedo light reflected off the ground — such as white gravel or light-colored concrete. Under favorable albedo conditions, energy yield gains of several percentage points over a standard monofacial panel are achievable. ### Are S-Energy SL45-78BGI panels suited for large-scale PV farms? Yes, the SL45-78BGI series is designed for commercial rooftop and utility-scale PV installations. Compatibility with 1500 V systems allows more modules per string, reducing wiring runs and overall balance-of-system (BoS) costs. The 485 Wp peak power rating and positive power tolerance simplify yield planning and financial modeling for larger projects. ### How do S-Energy SL45-78BGI modules differ from standard monofacial monocrystalline panels? The key differences are the bifacial construction and PERC cell technology. A standard monofacial panel captures only direct solar irradiance from the front, while the SL45-78BGI also absorbs reflected light through the rear cell surface. Anti-reflective coated tempered glass further improves light transmission and mechanical durability, resulting in higher overall energy yield at comparable installation cost. ### Is S-Energy a reliable manufacturer — what should I know before buying the SL45-78BGI? S-Energy is a South Korean manufacturer with roots in Samsung's photovoltaic division. The company does not currently appear on Bloomberg NEF Tier 1 lists and has reported financial losses in recent years. Given that the SL45-78BGI is also discontinued, buyers should factor in potential warranty support risk. Always verify IEC 61215 and IEC 61730 certifications when sourcing panels from remaining stock. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/sl45-78bgi-xxxs-230809-cf14db53e72a.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Longi Solar LR7-54HJD-510M](https://comparepv.com/panel/longi-lr7-54hjd-510m) | 510 W | Cooler, +4.8 pp, +5 yr warranty | | [AIKO AIKO-A495-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a495-mce54mw) | 495 W | Cooler, lighter, +4.6 pp | | [Longi Solar LR7-54HJD-505M](https://comparepv.com/panel/longi-lr7-54hjd-505m) | 505 W | Cooler, +4.5 pp, +5 yr warranty | | [AIKO AIKO-A490-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a490-mce54mw) | 490 W | Cooler, lighter, +4.3 pp | | [Longi Solar LR7-54HJD-500M](https://comparepv.com/panel/longi-lr7-54hjd-500m) | 500 W | Cooler, +4.3 pp, +5 yr warranty | | [Talesun CIPRO-TN9C54M-500W](https://comparepv.com/panel/talesun-cipro-tn9c54m-500w) | 500 W | Cooler, lighter, +4.3 pp | | [S-Energy SL45-78BGI-480S](https://comparepv.com/panel/s-energy-sl45-78bgi-480s) | 480 W | Very close match | | [S-Energy SL45-78BGI-485S](https://comparepv.com/panel/s-energy-sl45-78bgi-485s) | 485 W | +10 W, +0.4 pp | | [AIKO AIKO-A650-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a650-mae72mw) | 650 W | +175 W, cooler, +5.0 pp | | [AIKO AIKO-A645-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a645-mae72mw) | 645 W | +170 W, cooler, +4.8 pp | | [AIKO AIKO-A640-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a640-mae72mw) | 640 W | +165 W, cooler, +4.6 pp | | [AIKO AIKO-A635-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a635-mae72mw) | 635 W | +160 W, cooler, +4.4 pp | | [AIKO AIKO-A630-MAH72Dw](https://comparepv.com/panel/aiko-aiko-a630-mah72dw) | 630 W | +155 W, cooler, +4.2 pp | --- Source: https://comparepv.com/panel/s-energy-sl45-78bgi-475s 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.