--- title: "Talesun TP8F66M-665 665W Solar Panel - Specs & Review | ComparePV" description: "Talesun TP8F66M-665 665W solar panel. Specs: 21.40% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/talesun-tp8f66m-665" updated: 2026-09-11 --- # Talesun TP8F66M-665 Middle of its segment, short guarantee 320 panels in the segment PERC 650-700 W ## Identity - **Manufacturer:** Talesun - **Model:** TP8F66M-665 - **Series:** BISTAR TP8F66M / TP8F66M(H) - **Rated power:** 665 W - **Cell technology:** PERC ## How it compares Compared against segment PERC 650-700 W (320 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 665 W | 660 W | Typical | | | Module efficiency | 21.40% | 21.25% | Typical | 8,323 | | Power density | 214.1 | 212.5 | Typical | 8,250 | | Temperature coefficient | -0.340 | -0.340 | Typical | 8,778 | | Weight (kg) | 34.5 kg | 34.5 kg | Typical | | | Performance warranty | 25 yrs | 30 yrs | Weak - bottom 21% | 9,798 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 21.40% | 21.25% | Typical | 8,323 | | Power density | 214.1 | 212.5 | Typical | 8,250 | | Temperature coefficient | -0.340 | -0.340 | Typical | 8,778 | | Weight per kWp | 51.9 | 52.3 | Typical | 5,294 | | Performance warranty | 25 yrs | 30 yrs | Weak - bottom 21% | 9,798 | ### Watch out for - **25 year performance warranty** - Bottom 21% of the PERC 650-700 W segment, against a median of 30 yrs. - **Best for:** Commercial, utility-scale and shaded-installations. - **Not ideal for:** Owners who want a long output guarantee. ## Specification ### Electrical - **Rated power (Pmax):** 665 W - **Efficiency:** 21.40 % - **Voltage at Pmax (Vmp):** 38.40 V - **Current at Pmax (Imp):** 17.32 A - **Open-circuit voltage (Voc):** 46.00 V - **Short-circuit current (Isc):** 18.41 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.340 %/degC - **Temperature coefficient of Voc:** -0.250 %/degC - **Temperature coefficient of Isc:** 0.046 %/degC - **NOCT:** 43 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** PERC - **Cell count:** 132 ### Physical - **Length:** 2384 mm - **Width:** 1303 mm - **Thickness:** 35 mm - **Weight:** 34.5 kg - **Area:** 3.11 m2 - **Power density:** 214.1 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:** 546 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 8323 of 14005 | | Power density | 8250 of 14005 | | Temperature coefficient | 8778 of 14005 | | Weight | 5294 of 14005 | | Warranty | 9798 of 14005 | ## About this series The Talesun BISTAR TP8F66M / TP8F66M(H) series is designed for large-scale installations where stable module performance, minimal energy losses, and predictable energy yield are crucial. The application of **12BB technology** and **half-cell cells** enhances current flow within the module and supports higher efficiency in real-world conditions - especially under partial shading and uneven irradiance. A characteristic feature of this series is the **new wiring layout**, which minimizes internal losses and helps better manage operating temperature, reducing the risk of localized overheating. Another distinguishing feature is **enhanced PID resistance**, verified through testing, which is particularly important for systems operating at high system voltages. In practice, the TP8F66M and TP8F66M(H) will excel in solar farms, commercial rooftops, and projects where lower energy costs throughout the entire life cycle are a priority. The complete solution is complemented by an **IP68 junction box**, ideal for demanding weather conditions. ## Notable figures - At 21.4% efficiency, this panel is on par with typical \*\*PERC 650-700W\*\* modules - Power density of 214.1 W/m² matches the \*\*PERC 650-700W\*\* median - Temperature coefficient of -0.34%/°C matches the \*\*PERC 650-700W\*\* median - #8323 for efficiency, #8778 for temperature performance out of 14005 panels ## Questions ### What is the product and power warranty for Talesun BISTAR TP8F66M panels? The TP8F66M series comes with a 12-year product warranty and a 25-year linear power output warranty. Talesun is a Tier 1 manufacturer, which adds extra confidence for long-term investment - in practice this means predictable energy yield throughout the system's lifetime, even in large-scale PV farm projects where long-term parameter stability is key to a solid return on investment. ### How do the half-cut cells used in the TP8F66M differ from standard full-size cells? Half-cut cells split a standard cell into two halves, reducing current losses and internal module resistance. Combined with the 12BB (12 busbar) technology used in the TP8F66M, this improves current flow and boosts efficiency, especially under partial shading from clouds, chimneys, or dirt - the module then loses less power than a panel built with full-size cells. ### Are Talesun TP8F66M panels suitable for large solar farms and industrial rooftop installations? Yes, the TP8F66M series was specifically designed for utility-scale projects such as PV farms, warehouse, and industrial building rooftops. Power output up to 670 Wp reduces the number of modules needed to reach a given system capacity, lowering installation, cabling, and mounting structure costs per installed kilowatt - which helps reduce LCOE in commercial-scale projects. ### What does enhanced PID resistance in the TP8F66M mean and why does it matter? PID (Potential Induced Degradation) is a gradual power loss caused by high system voltage acting on the cells. Talesun confirms enhanced PID resistance for the TP8F66M series through testing, which matters in large installations operating at high DC voltages - it reduces the risk of premature performance drop and supports stable energy production throughout the warranty period. ### Are Talesun BISTAR TP8F66M panels bifacial modules? No, the TP8F66M series consists of monofacial panels built on PERC cell technology. This means they generate power only from the front surface, unlike bifacial panels that also capture light reflected from the ground. This design works well for standard rooftop and ground-mount installations where the rear side of the module has no access to light. ### Does Talesun, as a manufacturer, guarantee high quality and investment security for the TP8F66M panels? Talesun is a Chinese Tier 1 manufacturer, meaning the company has an established production track record, stable financials, and is regularly audited by independent financial institutions. The TP8F66M panels also feature an IP68-rated junction box, resistant to moisture and dust, ensuring reliable operation in demanding weather conditions throughout the system's operating life. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/32488383863031c8275dd3-11a4de096383.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A650-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a650-mae72mw) | 650 W | Cooler, lighter, +3.8 pp | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | Cooler, lighter, +3.8 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | Cooler, lighter, +3.6 pp | | [AIKO AIKO-A645-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a645-mae72mw) | 645 W | Cooler, lighter, +3.6 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | Cooler, +3.6 pp, +5 yr warranty | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | Cooler, +3.5 pp, +5 yr warranty | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | Cooler, lighter, +3.4 pp | | [Talesun TP8F66M-650](https://comparepv.com/panel/talesun-tp8f66m-650) | 650 W | -15 W, -0.5 pp | | [Talesun TP8F66M-655](https://comparepv.com/panel/talesun-tp8f66m-655) | 655 W | -10 W, -0.3 pp | | [Talesun TP8F66M-660](https://comparepv.com/panel/talesun-tp8f66m-660) | 660 W | Very close match | | [Talesun TD8G66M/670W](https://comparepv.com/panel/talesun-td8g66m-670w) | 670 W | Heavier, +0.2 pp, +5 yr warranty | | [AIKO AIKO-A805-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a805-grh78dw) | 805 W | +140 W, cooler, +3.7 pp | | [AIKO AIKO-A800-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a800-grh78dw) | 800 W | +135 W, cooler, +3.5 pp | | [AIKO AIKO-A795-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a795-grh78dw) | 795 W | +130 W, cooler, +3.4 pp | | [AIKO AIKO-A790-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a790-grh78dw) | 790 W | +125 W, cooler, +3.2 pp | | [Trina Solar TSM-NEG21C.20Q-760](https://comparepv.com/panel/trina-solar-tsm-neg21c-20q-760) | 760 W | +95 W, cooler, +3.1 pp | --- Source: https://comparepv.com/panel/talesun-tp8f66m-665 Not in this file, on the page: a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.