--- title: "Tongwei TWMHF-66HD710 Solar Panel: Specs & Datasheet | ComparePV" description: "Tongwei TWMHF-66HD710 solar panel. Specs: 22.90% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/tongwei-twmhf-66hd710" image: "https://comparepv.com/og/panel/tongwei-twmhf-66hd710.png" updated: 2026-09-11 --- # Tongwei TWMHF-66HD710 Solid all-round for its segment 222 panels in the segment HJT 700-750 W ## Identity - **Manufacturer:** Tongwei - **Model:** TWMHF-66HD710 - **Series:** TWMHF - **Rated power:** 710 W - **Cell technology:** HJT - **Bifacial:** yes ## How it compares Compared against segment HJT 700-750 W (222 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 710 W | 715 W | Typical | | | Module efficiency | 22.90% | 23.02% | Typical | 2,412 | | Power density | 228.6 | 230.2 | Typical | 2,529 | | Temperature coefficient | -0.240 | -0.240 | Typical | 13 | | Weight (kg) | 37.5 kg | 38.3 kg | Typical | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 22.90% | 23.02% | Typical | 2,412 | | Power density | 228.6 | 230.2 | Typical | 2,529 | | Temperature coefficient | -0.240 | -0.240 | Typical | 13 | | Weight per kWp | 52.8 | 53.6 | Typical | 6,552 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | - **Best for:** Utility-scale and hot-climate. ## Specification ### Electrical - **Rated power (Pmax):** 710 W - **Efficiency:** 22.90 % - **Voltage at Pmax (Vmp):** 42.47 V - **Current at Pmax (Imp):** 16.72 A - **Open-circuit voltage (Voc):** 50.44 V - **Short-circuit current (Isc):** 17.57 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.240 %/degC - **Temperature coefficient of Voc:** -0.220 %/degC - **Temperature coefficient of Isc:** 0.040 %/degC - **NOCT:** 44 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** HJT - **Cell count:** 132 - **Bifacial:** yes - **Bifacial gain:** 25.00 ### Physical - **Length:** 2384 mm - **Width:** 1303 mm - **Thickness:** 35 mm - **Weight:** 37.5 kg - **Area:** 3.11 m2 - **Power density:** 228.6 Wp/m2 ### Warranty and degradation - **Product warranty:** 15 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 88.1 % - **First-year degradation:** 1.00 % - **Annual degradation:** 0.38 % - **Output after 30 years:** 626 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 2412 of 14129 | | Power density | 2529 of 14129 | | Temperature coefficient | 13 of 14129 | | Weight | 6552 of 14129 | | Warranty | 21 of 14129 | ## About this series Tongwei TWMHF photovoltaic panels are an advanced solution based on **HJT cell technology**, which pushes the efficiency limits of traditional silicon modules. This series combines the advantages of crystalline and thin-film silicon, which translates into exceptional energy conversion efficiency even on heavily cloudy days. A key advantage of the design is an extremely **low temperature coefficient**, thanks to which the modules lose significantly less power on hot days compared to standard P-type technologies. The use of N-type cells completely eliminates light-induced degradation, ensuring stable parameters for decades. The TWMHF series solves the problem of limited installation space by offering **maximization of energy yield per square meter**, making it an ideal choice for demanding prosumers and photovoltaic farms focused on a fast return on investment. What distinguishes them from competitors' products is the use of an innovative **bifacial structure**, allowing for the effective use of reflected light. Solid construction and high resistance to mechanical loads guarantee installation safety in the variable Polish climate. This is a product dedicated to investors seeking uncompromising quality and the latest solar engineering achievements that realistically increase the profitability of every PV system. ## Notable figures - Efficiency of 22.9% matches the \*\*HJT 700-750W\*\* median - Power density of 228.6 W/m² matches the \*\*HJT 700-750W\*\* median - Temperature coefficient of -0.24%/°C matches the \*\*HJT 700-750W\*\* median - 90% bifaciality enables rear-side power generation, boosting yield by 4-14% on reflective surfaces - Ranked #2412 out of 14129 panels for efficiency in the database ## Questions ### What is HJT technology used in Tongwei TWMHF panels and how does it differ from PERC or TOPCon? HJT (heterojunction) combines crystalline silicon with thin amorphous silicon layers, delivering higher conversion efficiency and lower thermal losses than classic PERC cells. Compared to TOPCon, HJT cells have an even lower temperature coefficient and perform better under diffuse light, such as on cloudy days, resulting in higher energy yield under variable irradiance conditions. ### Are bifacial Tongwei TWMHF panels worth installing on a pitched roof, or only on the ground? The bifacial design works best on ground-mounted racking, carports, or elevated flat-roof installations, where the rear side can capture light reflected from the ground. On a standard pitched roof, the bifacial gain is limited due to lack of space beneath the panel, but the module still performs well as a high-efficiency monofacial panel. ### What warranty do Tongwei TWMHF solar panels come with? TWMHF panels are backed by a 15-year product warranty and a 30-year linear power warranty, exceeding the standard 25 years typical of PERC-based modules. The extended power warranty results from the N-type cells, which are not subject to light-induced degradation (LID), making power output decline slower and more predictable over the panel's lifetime. ### Do Tongwei TWMHF panels lose less power on hot days than standard modules? Yes, a key advantage of HJT technology is a very low power temperature coefficient, meaning the module loses significantly less efficiency as cell temperature rises above 25°C. In practice, on hot sunny days a TWMHF panel generates higher energy yield than a comparably rated P-type module, which experiences noticeably larger power drops in heat. ### Are Tongwei TWMHF panels rated up to 720 Wp suitable for limited roof space? Yes, the high unit power of up to 720 Wp allows a higher total system capacity with fewer modules, which is valuable on limited roof space. This maximizes energy production per square meter, a benefit especially appreciated by installers working on small or irregularly shaped roofs where achieving target system power is otherwise difficult. ### Is the Tongwei TWMHF series still available for purchase? The TWMHF series has been discontinued by Tongwei and replaced by newer HJT module families. Units may still be available through distributors as remaining stock, but buyers should verify current inventory and confirm warranty support with the seller, since the manufacturer no longer accepts new orders for this specific model. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/6e2847c921a578a81f7719192df2ccca-7e3110f1b1eb.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | -30 W, lighter, +2.3 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | -35 W, lighter, +2.1 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | Hotter, lighter, +2.1 pp | | [WINAICO WST-675BKX72-A2](https://comparepv.com/panel/winaico-wst-675bkx72-a2) | 675 W | -35 W, lighter, +2.1 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | Hotter, lighter, +2.0 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | -40 W, lighter, +1.9 pp | | [Longi Solar LR7-72HVHF-670M](https://comparepv.com/panel/longi-lr7-72hvhf-670m) | 670 W | -40 W, lighter, +1.9 pp | | [Jinko Solar JKM650-670N-66QL6-BDV (670W class)](https://comparepv.com/panel/jinko-solar-jkm650-670n-66ql6-bdv-670w-class) | 670 W | -40 W, lighter, +1.9 pp | | [Tongwei TWMPF-66HD655](https://comparepv.com/panel/tw-solar-tongwei-twmpf-66hd655) | 655 W | -55 W, hotter, -1.8 pp | | [Tongwei TWMPF-66HD660](https://comparepv.com/panel/tw-solar-tongwei-twmpf-66hd660) | 660 W | -50 W, hotter, -1.7 pp | | [Tongwei TWMPF-66HD665](https://comparepv.com/panel/tw-solar-tongwei-twmpf-66hd665) | 665 W | -45 W, hotter, -1.5 pp | | [Tongwei TWMPF-66HD670](https://comparepv.com/panel/tw-solar-tongwei-twmpf-66hd670) | 670 W | -40 W, hotter, -1.3 pp | | [Tongwei TWMPF-66HD675](https://comparepv.com/panel/tw-solar-tongwei-twmpf-66hd675) | 675 W | -35 W, hotter, -1.2 pp | | [Tongwei TWMNF-66HD700XX](https://comparepv.com/panel/tw-solar-tongwei-twmnf-66hd700xx) | 700 W | -10 W, hotter, -0.4 pp | | [Tongwei TWMNF-66HD705](https://comparepv.com/panel/tongwei-solar-twmnf-66hd705) | 705 W | Hotter | | [AIKO AIKO-A805-GRH78Dw](https://comparepv.com/panel/aiko-aiko-a805-grh78dw) | 805 W | +95 W, heavier, +2.2 pp | --- Source: https://comparepv.com/panel/tongwei-twmhf-66hd710 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.