--- title: "Bisol BBO 520 520W Solar Panel - Specs & Review | ComparePV" description: "Bisol BBO 520 520W solar panel. Specs: 23.20% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/bisol-bbo-520" updated: 2026-09-11 --- # Bisol BBO 520 Light for its output, no clear weak spot 432 panels in the segment TOPCon 500-550 W ## Identity - **Manufacturer:** Bisol - **Model:** BBO 520 - **Series:** BISOL Duplex - **Rated power:** 520 W - **Cell technology:** TOPCon ## How it compares Compared against segment TOPCon 500-550 W (432 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 520 W | 510 W | Typical | | | Module efficiency | 23.20% | 22.73% | Strong - top 16% | 1,306 | | Power density | 232.2 | 227.4 | Strong - top 14% | 1,328 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,165 | | Weight (kg) | 23.5 kg | 27.0 kg | Strong - top 6% | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 23.20% | 22.73% | Strong - top 16% | 1,306 | | Power density | 232.2 | 227.4 | Strong - top 14% | 1,328 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,165 | | Weight per kWp | 45.2 | 52.4 | Strong - top 6% | 635 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Strengths - **45.2 kg per kWp** - Top 6% of the TOPCon 500-550 W segment, against a median of 52.4. Ranked 635th in the whole database. - **232.2 watts per square metre** - Top 14% of the TOPCon 500-550 W segment, against a median of 227.4. - **23.20% module efficiency** - Top 16% of the TOPCon 500-550 W segment, against a median of 22.73%. - **Best for:** Residential, commercial and shaded-installations. ## Specification ### Electrical - **Rated power (Pmax):** 520 W - **Efficiency:** 23.20 % - **Voltage at Pmax (Vmp):** 33.80 V - **Current at Pmax (Imp):** 15.40 A - **Open-circuit voltage (Voc):** 40.60 V - **Short-circuit current (Isc):** 16.20 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.290 %/degC - **Temperature coefficient of Voc:** -0.250 %/degC - **Temperature coefficient of Isc:** 0.050 %/degC - **NOCT:** 42 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** TOPCon - **Cell count:** 108 ### Physical - **Length:** 1975 mm - **Width:** 1134 mm - **Thickness:** 35 mm - **Weight:** 23.5 kg - **Area:** 2.24 m2 - **Power density:** 232.2 Wp/m2 ### Warranty and degradation - **Product warranty:** 25 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 90.0 % - **First-year degradation:** 1.00 % - **Annual degradation:** 0.31 % - **Output after 30 years:** 468 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 1306 of 14005 | | Power density | 1328 of 14005 | | Temperature coefficient | 2165 of 14005 | | Weight | 635 of 14005 | | Warranty | 21 of 14005 | ## Pros - **30-Year Linear Power Warranty** - The manufacturer guarantees a minimum efficiency of 85% over 30 years, while comparable series (DAH DHN-60R18/DG, Silfab Commercial NTC) offer a standard 25-year warranty. The extended power output protection meaningfully reduces investment risk in LCOE calculations for commercial installations and utility-scale PV plants. - **European Manufacturing – Slovenia** - The Slovenian production facility eliminates exposure to import tariffs on Asian-manufactured modules (the EU has repeatedly considered and imposed trade defense measures against Chinese producers) and shortens the supply chain. BISOL has earned the Top Brand PV award in four European markets (Belgium, France, Italy, and Slovenia) and maintains a warranty claim rate of 0.01% across two decades of operation, with no reported cases of delamination. - **22–23.2% Efficiency – Above Segment Median** - The efficiency range of 22–23.2% positions this series clearly above the Silfab Commercial NTC (21.9%) and on par with the DAH DHN-60R18/DG (23%). For a typical residential prosumer system of 10 kWp, the difference versus Silfab translates to approximately 50–80 kWh of additional annual yield for the same roof area. - **Bifacial Technology – Rear-Side Gain Up to 60%** - BBO series modules generate energy from both sides of the panel; the manufacturer claims a rear-side gain of up to 60% of nominal power output depending on ground albedo (light-colored gravel, white roofing membrane, snow). Compared to conventional monofacial modules, this results in meaningfully higher annual energy yield without increasing the installation footprint. - **Half-Cut Cells + Multi-Busbar – Shade Resilience** - The combination of 132 half-cut cells and a multi-busbar electrode grid minimizes resistive losses and reduces the impact of partial shading on the output of the entire string — a critical feature for rooftop installations with obstructions such as chimneys and dormers. ## Cons - **No BNEF Tier-1 Status** - BISOL does not appear on the BloombergNEF Tier 1 bankable manufacturers list, which may complicate or increase the cost of debt financing for commercial projects and utility-scale PV farms where financial institutions require Tier-1 status from module suppliers. The manufacturer has issued an official statement challenging the list's methodology; however, the bankability requirement remains a real constraint for project-financed developments. - **Lower Efficiency Than Jinko Tiger Neo (24.06%)** - The competing Jinko Solar Tiger Neo III 51QL6-BDV achieves 24.06% efficiency at the same 520 Wp power class through N-type TOPCon cell technology, offering approximately 0.9 percentage points higher efficiency and a lower temperature degradation coefficient (–0.26%/°C vs. a typical –0.34%/°C for P-type PERC cells). For installations with severely constrained roof area, this difference is measurable. ## About this series The BISOL Duplex BBO series are **bidirectional (bifacial) photovoltaic modules** based on half-cut monocrystalline cells, which generate energy from both the front and back sides of the panel. Thanks to the bifacial technology, these modules can achieve **up to 60% energy gain from the rear side** - depending on the type of ground beneath the installation - which significantly increases energy yield compared to traditional monofacial panels. The combination of **half-cut technology with a multi-busbar (multi-wire electrode) system** minimizes resistive losses and significantly improves resistance to partial shading. The 3.2 mm thick tempered glass provides superior mechanical strength, unavailable in typical market modules. BISOL Duplex BBO **is manufactured in Europe** with strict quality control, as evidenced by the record-low defect rate of 0.01% and the absence of any reported cases of moisture ingress or delamination after two decades of operation. This series is suitable for residential, commercial, and large-scale PV installations. **A 25-year linear warranty on energy production with a minimum efficiency of 85%** makes these modules a reliable choice for investors seeking long-term returns. ## Notable figures - Efficiency of 23.2% matches the \*\*TOPCon 500-550W\*\* median - At 232.2 W/m² power density, this panel generates 4.8 W/m² more per unit area than \*\*TOPCon 500-550W\*\* median (227.4 W/m²) - At -0.29%/°C, hot weather performance is typical for \*\*TOPCon 500-550W\*\* panels - At 23.5 kg, this panel is 3.5 kg lighter than \*\*TOPCon 500-550W\*\* median (27.0 kg) - easier handling during installation - Ranked #1306 out of 14005 panels for efficiency in the database ## Questions ### What warranty is offered on the BISOL Duplex BBO panels and what does it cover? The BISOL Duplex BBO series comes with a 25-year product warranty covering manufacturing defects and a 30-year linear power output warranty guaranteeing a minimum of 85% of nominal efficiency after 25 years of operation. The manufacturer substantiates this quality commitment with a historically low warranty claim rate of 0.01% and zero recorded cases of delamination or moisture ingress over two decades of field deployment. ### Are BISOL Duplex BBO panels manufactured in Europe, and does that matter? Yes, the BISOL Duplex BBO series is designed and manufactured in Europe by the Slovenian company BISOL Group. European production means rigorous quality control in compliance with EU standards, a shorter supply chain, and no exposure to import tariff risk. In practice, this translates to consistent module parameters and faster access to warranty service without intermediaries outside Europe. ### What is the half-cut and multi-busbar technology used in the BISOL Duplex BBO series? Half-cut technology involves laser-cutting each cell in half, which reduces the operating current and lowers resistive losses. Multi-busbar technology — a dense wire-based electrode grid — shortens current-flow paths and reduces shading of the active cell surface. The combined result is higher output under partial shading conditions (e.g., from a chimney or dormer window) and reduced long-term cell degradation. ### How much does a BISOL Duplex BBO 520W panel weigh, and can it be installed on a typical pitched roof? The BISOL Duplex BBO 520 Wp module weighs approximately 26 kg and measures 2094 × 1134 × 35 mm. These are standard dimensions for 500+ Wp class modules. Most conventional pitched roofs with ceramic tile or trapezoidal metal sheet covering can accommodate such an installation; however, prior to mounting it is recommended that the structural load capacity of the roof truss be verified by a qualified installer or structural engineer. ### What is the peak efficiency of the BISOL Duplex BBO panels, and are they a good choice for a residential installation? BISOL Duplex BBO panels achieve a module efficiency of up to 21.5%, placing them in the upper tier of the monocrystalline module market. With a peak power of 520 Wp, they enable a high-yield residential system on a limited roof area. For a typical single-family home, this means fewer panels are needed to achieve the same energy output compared to standard 380–400 Wp modules. ### Is BISOL a Tier 1 manufacturer, and should the absence of a Tier 1 rating be a concern? BISOL Group is not classified as a Tier 1 manufacturer under BloombergNEF rankings; however, its European origin, over 20 years of operational history, a warranty claim rate of 0.01%, and a 25-year product warranty provide robust, independently verifiable indicators of manufacturer reliability. It is important to note that the Tier 1 classification primarily assesses a manufacturer's financial capacity to honor warranty obligations — not module quality itself — and should therefore not be used as the sole selection criterion. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/BISOL_Duplex_BBO_EN-18e6e8ca4e47.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Longi Solar LR7-54HJD-510M](https://comparepv.com/panel/longi-lr7-54hjd-510m) | 510 W | -10 W, cooler, +1.8 pp | | [AIKO AIKO-A495-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a495-mce54mw) | 495 W | -25 W, cooler, +1.6 pp | | [Longi Solar LR7-60HVH-560M](https://comparepv.com/panel/longi-lr7-60hvh-560m) | 560 W | +40 W, cooler, +1.6 pp | | [Longi Solar LR7-54HJD-505M](https://comparepv.com/panel/longi-lr7-54hjd-505m) | 505 W | -15 W, cooler, +1.5 pp | | [Longi Solar LR7-60HVH-555M](https://comparepv.com/panel/longi-lr7-60hvh-555m) | 555 W | +35 W, cooler, +1.4 pp | | [AIKO AIKO-A490-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a490-mce54mw) | 490 W | -30 W, cooler, +1.3 pp | | [Longi Solar LR7-54HJD-500M](https://comparepv.com/panel/longi-lr7-54hjd-500m) | 500 W | -20 W, cooler, +1.3 pp | | [Bisol BBO 500](https://comparepv.com/panel/bisol-bbo-500) | 500 W | -20 W, -0.9 pp | | [Bisol BBO 510](https://comparepv.com/panel/bisol-bbo-510) | 510 W | -10 W, -0.4 pp | | [Longi Solar LR7-60HVHL-550M](https://comparepv.com/panel/longi-lr7-60hvhl-550m) | 550 W | +30 W, lighter, +1.2 pp | | [JA Solar JAT60S40-540/LR](https://comparepv.com/panel/ja-solar-jat60s40-540-lr) | 540 W | +20 W, cooler, +1.2 pp | | [Gokin GK-5-60HG-540M](https://comparepv.com/panel/gokin-gk-5-60hg-540m) | 540 W | +20 W, cooler, +1.2 pp | | [Jinko Solar JKM545-54QL6-DV-F1-EU](https://comparepv.com/panel/jinko-solar-jkm545-54ql6-dv-f1-eu) | 545 W | Cooler, heavier, +1.1 pp | | [Longi Solar LR7-60HVH-545M](https://comparepv.com/panel/longi-lr7-60hvh-545m) | 545 W | +25 W, cooler, +1.0 pp | --- Source: https://comparepv.com/panel/bisol-bbo-520 Not in this file, on the page: the I-V and temperature curves lifted from the manufacturer's datasheet, a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.