--- title: "EGing PV EG-685NT66-HU/BF-DG 685W Solar Panel - Specs & Review | ComparePV" description: "EGing PV EG-685NT66-HU/BF-DG 685W solar panel. Specs: 22.05% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/eging-pv-eg-685nt66-hu-bf-dg" updated: 2026-09-11 --- # EGing PV EG-685NT66-HU/BF-DG Middle of its segment, heavy for its output 249 panels in the segment TOPCon 650-700 W ## Identity - **Manufacturer:** EGing PV - **Model:** EG-685NT66-HU/BF-DG - **Series:** AURORA Pro SERIES - **Rated power:** 685 W - **Cell technology:** TOPCon - **Bifacial:** yes ## How it compares Compared against segment TOPCon 650-700 W (249 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 685 W | 665 W | Typical | | | Module efficiency | 22.05% | 22.40% | Weak - bottom 24% | 6,233 | | Power density | 220.5 | 223.7 | Weak - bottom 25% | 6,208 | | Temperature coefficient | -0.300 | -0.290 | Typical | 6,093 | | Weight (kg) | 38.3 kg | 34.6 kg | Weak - bottom 21% | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 22.05% | 22.40% | Weak - bottom 24% | 6,233 | | Power density | 220.5 | 223.7 | Weak - bottom 25% | 6,208 | | Temperature coefficient | -0.300 | -0.290 | Typical | 6,093 | | Weight per kWp | 55.9 | 53.2 | Weak - bottom 21% | 10,276 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Watch out for - **55.9 kg per kWp** - Bottom 21% of the TOPCon 650-700 W segment, against a median of 53.2. - **22.05% module efficiency** - Bottom 24% of the TOPCon 650-700 W segment, against a median of 22.40%. - **220.5 watts per square metre** - Bottom 25% of the TOPCon 650-700 W segment, against a median of 223.7. - **Best for:** Residential, commercial, utility-scale and shaded-installations. - **Not ideal for:** Weight-limited structures, tight roof space and roofs where every square metre has to count. ## Specification ### Electrical - **Rated power (Pmax):** 685 W - **Efficiency:** 22.05 % - **Voltage at Pmax (Vmp):** 39.85 V - **Current at Pmax (Imp):** 17.19 A - **Open-circuit voltage (Voc):** 47.64 V - **Short-circuit current (Isc):** 18.22 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.300 %/degC - **Temperature coefficient of Voc:** -0.250 %/degC - **Temperature coefficient of Isc:** 0.040 %/degC - **NOCT:** 44 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** TOPCon - **Cell count:** 132 - **Bifacial:** yes - **Bifacial gain:** 20.00 ### Physical - **Length:** 2384 mm - **Width:** 1303 mm - **Thickness:** 35 mm - **Weight:** 38.3 kg - **Area:** 3.11 m2 - **Power density:** 220.5 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 87.4 % - **First-year degradation:** 1.00 % - **Annual degradation:** 0.40 % - **Output after 30 years:** 599 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 6233 of 14005 | | Power density | 6208 of 14005 | | Temperature coefficient | 6093 of 14005 | | Weight | 10276 of 14005 | | Warranty | 21 of 14005 | ## Pros - **N-type TOPCon: Low Temperature Coefficient** - The N-type TOPCon cells in the AURORA Pro series exhibit a temperature coefficient of Pmax of -0.31%/°C, a notably better result than typical P-type PERC modules (-0.35 to -0.40%/°C). In practice, this translates to 5–10% higher energy yield on hot summer days when module temperature exceeds 50–60°C. - **30-Year Linear Power Warranty ≥87.4%** - The manufacturer guarantees degradation of ≤1% in the first year and ≤0.4%/year in subsequent years, resulting in ≥87.4% of nominal power after 30 years. Standard P-type PERC modules from leading suppliers (JA Solar, Trina) typically offer a 25-year warranty with output declining to ~84.8%, making EGing's warranty genuinely more advantageous for investors calculating long-term IRR. - **Bifacial Design – Additional Yield from the Rear Side** - The bifacial construction enables energy harvesting from light reflected off the ground surface (albedo). With typical ground albedo values of 0.2–0.3 (light gravel, EPDM membrane), the bifacial gain amounts to 5–15% annually, significantly improving LCOE in ground-mount or flat-roof installations without increasing the system's footprint. - **Confirmed BNEF Tier-1 Status** - EGing PV appears on the official BNEF Tier-1 PV Module Manufacturers list (confirmed at least since Q2 2024), enabling non-recourse project financing for utility-scale solar farms and supporting higher asset valuations upon potential resale. The company has been operating since 2003 and holds a manufacturing capacity of >25 GW per year. - **Wide Power Range – 11 Variants (600–685 W)** - Eleven power variants spanning 600–685 Wp allow precise string sizing to match inverter requirements (MPP voltage, Isc) across both residential rooftop systems and commercial or utility-scale projects, eliminating the need for additional resistors or power converters. ## Cons - **Efficiency Below Closest TOPCon Competitors** - The series peaks at 22.05% efficiency, while comparable 210 mm TOPCon modules from Solarspace (SS9-66HD) and Seraphim (Sable) reach 22.21% at 690 Wp. The 0.16 percentage-point gap translates to approximately 0.7% lower yield per unit area — a meaningful disadvantage in space-constrained rooftop installations where every cm² contributes to revenue. ## About this series The AURORA Pro series sets a new standard for efficiency through the use of advanced **N-Type TOPCon cell** technology, which minimizes energy loss and significantly increases module efficiency. This solution effectively eliminates the problem of light-induced degradation, translating into stable power production for decades. These panels are characterized by an **excellent temperature coefficient**, which means they operate effectively even on hot days when traditional modules lose power. Thanks to its innovative construction, this series offers a higher yield per square meter, which is crucial for investors with limited roof space. AURORA Pro is an ideal choice for demanding residential and commercial installations, where **maximizing investment profitability** and a short payback period are what matters most. A distinguishing feature of the series is its exceptional resistance to extreme weather conditions and **increased efficiency in low light**, which in the Polish climate guarantees real profits even on cloudy days. It is an option for those seeking a technological advantage over standard P-Type solutions, ensuring superior system operation and a **longer linear performance warranty**, which effectively protects the investor's capital for years. ## Notable figures - Efficiency of 22.1% matches the \*\*TOPCon 650-700W\*\* median - 220.5 W/m² power density is 3.2 W/m² below \*\*TOPCon 650-700W\*\* median (223.7 W/m²) - requires larger installation area - Temperature coefficient of -0.30%/°C matches the \*\*TOPCon 650-700W\*\* median - At 38.3 kg (3.7 kg above \*\*TOPCon 650-700W\*\* median of 34.6 kg), requires checking roof load capacity - Bifacial design (100% factor) captures reflected light - adds 5-15% yield on ground-mount or white roof ## Questions ### What warranty does the EGing PV AURORA Pro panel carry and what does it cover? EGing PV AURORA Pro panels come with a 12-year product warranty and a 30-year linear power output warranty. This means the manufacturer guarantees that the module will maintain a specified minimum power output level for three decades. EGing PV holds Tier 1 manufacturer status, which reinforces confidence in the enforceability of these warranty commitments and provides genuine protection for the return on investment. ### What is TOPCon technology and why does the AURORA Pro series use it? TOPCon (Tunnel Oxide Passivated Contact) is a next-generation N-Type cell technology that uses a passivation layer to minimize charge carrier recombination. In practice, this translates to module efficiencies of up to 22.05% for the AURORA Pro, a low temperature coefficient of -0.31%/°C, and the effective elimination of Light-Induced Degradation (LID). Compared to the widely used P-Type PERC technology, this means more energy harvested from the same roof area over the entire system lifetime. ### Will the EGing PV AURORA Pro 685W panels perform well in the Polish climate with its high number of overcast days? Yes. The bifacial construction combined with N-Type TOPCon technology gives the AURORA Pro 685W enhanced low-light performance. The rear side of the module captures reflected irradiance even under diffuse radiation conditions, which are typical of Polish autumn and winter. The favorable temperature coefficient of -0.31%/°C also means reduced power losses during summer, when other panels experience significant output degradation during heat waves. ### What are the dimensions and weight of the EGing PV AURORA Pro 685W panel, and will it fit on a typical residential roof? The EGing PV AURORA Pro 685W module measures 2384 × 1303 × 35 mm and weighs 38.3 kg. This is a large-format module (66 cells), typical for commercial installations and larger single-family rooftops. Before purchasing, it is advisable to verify the load-bearing capacity of the roof structure and the availability of compatible mounting hardware, as modules of this size require robust racking systems specifically rated for large-format panels. ### What distinguishes the EGing PV AURORA Pro from the standard AURORA series without the Pro designation? The key difference lies in cell technology: the AURORA Pro series uses N-Type TOPCon cells, while the base AURORA relies on M-Type PERC technology. AURORA Pro achieves higher module efficiency (up to 22.05% vs. approximately 20%), offers a better temperature coefficient, and exhibits no LID. This results in greater annual energy yield and a longer linear power output warranty of 30 years, compared to the standard 25-year warranty on the base series. ### Are the AURORA Pro modules bifacial, and when is it worth choosing a bifacial configuration? Yes, EGing PV AURORA Pro panels are bifacial, meaning they generate electricity from both the front and rear surfaces of the module. The rear side captures light reflected from the ground, rooftop surface, or other nearby surfaces. The additional energy gain typically ranges from 5% to 15%, depending on the albedo of the surface beneath the array and the mounting tilt angle. Bifacial modules are particularly advantageous in ground-mounted installations, on flat roofs with a light-colored membrane, and in agrivoltaic systems. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/579436f5068703e-f835c6218bd4.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A650-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a650-mae72mw) | 650 W | Cooler, lighter, +3.1 pp | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | Cooler, lighter, +3.1 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | Cooler, lighter, +2.9 pp | | [AIKO AIKO-A645-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a645-mae72mw) | 645 W | -40 W, lighter, +2.9 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | Cooler, lighter, +2.9 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | Cooler, lighter, +2.8 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | Cooler, lighter, +2.8 pp | | [EGing PV EG-650M66-HU/BF-DG](https://comparepv.com/panel/eging-pv-eg-650m66-hu-bf-dg) | 650 W | -35 W, hotter, -1.1 pp | | [EGing PV EG-655M66-HU/BF-DG](https://comparepv.com/panel/eging-pv-eg-655m66-hu-bf-dg) | 655 W | -30 W, hotter, -1.0 pp | | [EGing PV EG-660NT66-HU/BF-DG](https://comparepv.com/panel/eging-pv-eg-660nt66-hu-bf-dg) | 660 W | -25 W, -0.8 pp | | [EGing PV EG-665NT66-HU/BF-DG](https://comparepv.com/panel/eging-pv-eg-665nt66-hu-bf-dg) | 665 W | -20 W, -0.7 pp | | [AIKO AIKO-A805-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a805-grh78dw) | 805 W | +120 W, cooler, +3.1 pp | | [AIKO AIKO-A800-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a800-grh78dw) | 800 W | +115 W, cooler, +2.8 pp | | [AIKO AIKO-A795-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a795-grh78dw) | 795 W | +110 W, cooler, +2.8 pp | | [AIKO AIKO-A790-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a790-grh78dw) | 790 W | +105 W, cooler, +2.6 pp | | [Trina Solar TSM-NEG21C.20Q-760](https://comparepv.com/panel/trina-solar-tsm-neg21c-20q-760) | 760 W | +75 W, cooler, +2.4 pp | --- Source: https://comparepv.com/panel/eging-pv-eg-685nt66-hu-bf-dg Not in this file, on the page: the I-V and temperature curves lifted from the manufacturer's datasheet, a thirty-year output simulator, a bifacial gain calculator and alternatives filtered by how closely they match these dimensions.