--- title: "DAH Solar DHN-78X16/DG-620W 620W Solar Panel - Specs & Review | ComparePV" description: "DAH Solar DHN-78X16/DG-620W 620W solar panel. Specs: 22.18% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/dah-dhn-78x16-dg-620w" updated: 2026-09-11 --- # DAH Solar DHN-78X16/DG-620W Middle of its segment, needs the roof space 1,086 panels in the segment TOPCon 600-650 W ## Identity - **Manufacturer:** DAH Solar - **Model:** DHN-78X16/DG-620W - **Series:** DHN-78X16/DG 620~640W - **Rated power:** 620 W - **Cell technology:** TOPCon - **Bifacial:** yes ## How it compares Compared against segment TOPCon 600-650 W (1086 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 620 W | 620 W | Typical | | | Module efficiency | 22.18% | 22.80% | Weak - bottom 9% | 5,930 | | Power density | 221.8 | 227.7 | Weak - bottom 9% | 5,869 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,165 | | Weight (kg) | 34.2 kg | 32.7 kg | Weak - bottom 15% | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 22.18% | 22.80% | Weak - bottom 9% | 5,930 | | Power density | 221.8 | 227.7 | Weak - bottom 9% | 5,869 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,165 | | Weight per kWp | 55.2 | 53.1 | Weak - bottom 15% | 9,586 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Watch out for - **221.8 watts per square metre** - Bottom 9% of the TOPCon 600-650 W segment, against a median of 227.7. Ranked 5,869th in the whole database. - **22.18% module efficiency** - Bottom 9% of the TOPCon 600-650 W segment, against a median of 22.80%. Ranked 5,930th in the whole database. - **55.2 kg per kWp** - Bottom 15% of the TOPCon 600-650 W segment, against a median of 53.1. - **Best for:** Commercial, utility-scale and hot-climate. - **Not ideal for:** Roofs where every square metre has to count, tight roof space and weight-limited structures. ## Specification ### Electrical - **Rated power (Pmax):** 620 W - **Efficiency:** 22.18 % - **Voltage at Pmax (Vmp):** 46.80 V - **Current at Pmax (Imp):** 13.25 A - **Open-circuit voltage (Voc):** 55.60 V - **Short-circuit current (Isc):** 14.08 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:** 0.046 %/degC - **NOCT:** 45 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** TOPCon - **Cell count:** 156 - **Bifacial:** yes - **Bifacial gain:** 25.00 ### Physical - **Length:** 2465 mm - **Width:** 1134 mm - **Thickness:** 34 mm - **Weight:** 34.2 kg - **Area:** 2.80 m2 - **Power density:** 221.8 Wp/m2 ### Warranty and degradation - **Product warranty:** 15 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 87.4 % - **Output after 30 years:** 542 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 5930 of 14005 | | Power density | 5869 of 14005 | | Temperature coefficient | 2165 of 14005 | | Weight | 9586 of 14005 | | Warranty | 21 of 14005 | ## Pros - **Up to 22.9% Efficiency – Top of the Segment** - The highest-wattage variant in the series (640 W) achieves 22.9% efficiency, matching the Suntech Ultra V Pro (22.9%) and clearly outperforming the REC Alpha Pro M (22.5%) and MY Solar HJT (22.61%). This translates into greater energy yield from the same roof or ground area without adding additional modules. - **30-Year Linear Power Warranty** - DAH guarantees ≥89.4% of nominal power output after 25 years and ≥87.4% after 30 years. By comparison, the REC Alpha Pro M series covers power output only through year 25 (92% at year 25), with no commitment for the following decade — a distinction that has a direct financial impact on LCOE calculations for utility-scale PV plants and commercial rooftop projects. - **Temperature Coefficient of -0.29%/°C** - The N-type TOPCon modules of the DHN-78X16/DG series lose only 0.29% of power per degree above STC (25°C). Standard PERC modules typically range from -0.35 to -0.40%/°C — a difference of 17–38% that results in measurably higher energy yields on hot summer days, when cell temperatures frequently exceed 55–65°C. - **Bifacial Double Glass – 5–25% Additional Energy Yield** - The bifacial double-glass construction harvests energy from light reflected off the ground surface, increasing production by 5–25% depending on surface albedo (white gravel, light-colored membrane, snow). The dual-glass design also eliminates the rear backsheet, which is susceptible to cracking and moisture ingress, thereby improving the module's long-term mechanical durability. - **BNEF Tier 1 – Bankability Confirmed Q4 2025** - DAH Solar has maintained BloombergNEF Tier 1 status for consecutive quarters, including Q1–Q4 2025. For projects requiring bank financing or leasing arrangements (utility-scale PV plants, ESCO schemes), Tier 1 classification is a prerequisite for module acceptance by financial institutions. ## Cons - **15-Year Product Warranty** - The workmanship and materials warranty stands at 15 years, whereas the REC Alpha Pro M series offers 20 years as standard (or 25 years under the REC ProTrust package through certified installers). In competitive tenders and due diligence reviews for commercial projects, the shorter manufacturer product warranty period may be a differentiating factor that works against DAH. ## About this series The DAH DHN-78X16/DG 620-640W series is designed to maximize energy yield from the same surface area, making it ideal for locations where every square meter of roof or ground space is valuable. The use of **N-type cells in TOPCon technology** helps minimize losses and maintain stable module performance even in challenging conditions, where competing solutions lose efficiency more quickly. The **double-glass bifacial design** also allows for energy harvesting from both sides, increasing production in installations on reflective surfaces or in elevated configurations. In practice, this series addresses a common problem with large-scale projects - how to increase production without adding more rows of modules - thanks to **high efficiency and large individual power output**. Another advantage is **excellent performance at high temperatures**, which translates to more predictable summer yields. This makes it a suitable choice for PV farms, commercial rooftops, and industrial applications, where the total cost of energy over the lifetime of the installation, combined with **long-term linear warranty**, is a key consideration. ## Notable figures - Module efficiency of 22.2% is 0.6pp below average for \*\*TOPCon 600-650W\*\* panels (median: 22.8%) - Power density of 221.8 W/m² is 5.9 W/m² below \*\*TOPCon 600-650W\*\* median (227.7 W/m²) - needs more roof space - At -0.29%/°C, hot weather performance is typical for \*\*TOPCon 600-650W\*\* panels - At 34.2 kg, this panel is 1.5 kg heavier than the \*\*TOPCon 600-650W\*\* median (32.7 kg) - more demanding for installation crews - Bifacial design (80% factor) captures reflected light - adds 4-12% yield on ground-mount or white roof ## Questions ### What warranty does the DAH Solar DHN-78X16/DG 620–640W series carry? The DHN-78X16/DG series is backed by a 15-year product warranty covering material and workmanship defects, along with a 30-year linear power output warranty. After 25 years the manufacturer guarantees at least 89.4% of nominal power, and after 30 years no less than 87.4%. This is one of the longest warranties in its product class—a critical factor when calculating investment returns over a multi-decade horizon. ### What is TOPCon technology and why does the DHN-78X16/DG series use it? TOPCon (Tunnel Oxide Passivated Contact) is an N-type cell technology that minimizes carrier recombination at cell contacts. In practice, this translates to higher module efficiency—the DHN-78X16/DG series reaches up to 22.9%—and lower power losses at elevated operating temperatures. For the system owner, this means more kilowatt-hours per square meter of installed area and more predictable energy yields throughout the entire service life. ### How does the DAH DHN-78X16/DG series perform during summer heat? The power temperature coefficient is -0.29%/°C, which is better than that of typical P-type PERC modules (usually -0.35%/°C). This means the module loses less power per degree above 25°C than older cell technologies. In summer, when rooftop surface temperatures can exceed 60°C, the difference in energy production between a TOPCon module and a PERC module becomes clearly measurable. ### Are the DAH Solar DHN-78X16/DG 640W panels suitable for utility-scale PV farms? Yes, the series is designed primarily for large-scale applications: utility-scale PV farms, industrial rooftops, and commercial installations. With up to 640 Wp per module and support for a 1500 V system voltage, it is possible to design longer strings and reduce the total number of inverters. The bifacial double-glass configuration is especially effective in ground-mounted systems over high-albedo surfaces, where the rear side of the module captures additional reflected irradiance. ### What are the advantages of the bifacial double-glass design in the DAH DHN-78X16/DG panels, and does it complicate installation? The bifacial design allows the cells to generate current from irradiance reflected off the ground surface (albedo gain), which can increase annual energy production by several to more than ten percent depending on the albedo of the surface and the tilt angle. The two glass lites replace the conventional rear backsheet, improving resistance to moisture ingress and mechanical damage. The module weighs approximately 34–35 kg, so installation requires at least two workers and a properly rated mounting structure. ### Is DAH Solar a reliable manufacturer, and where are the DHN-78X16/DG panels produced? DAH Solar is a Chinese manufacturer classified as Tier 1 by independent analytical agencies, indicating financial stability and consistent production quality. The DHN-78X16/DG series is manufactured in China. Tier 1 classification is an important criterion for banks and insurance companies when financing PV projects, and it also strengthens the buyer's negotiating position regarding warranty terms with the distributor. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/en-dhn-78x16-dg-620-635w-a26da74a545a.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A650-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a650-mae72mw) | 650 W | +30 W, lighter, +3.0 pp | | [AIKO AIKO-A645-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a645-mae72mw) | 645 W | Cooler, lighter, +2.8 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | +50 W, lighter, +2.6 pp | | [Longi Solar LR7-72HVHF-670M](https://comparepv.com/panel/longi-lr7-72hvhf-670m) | 670 W | +50 W, lighter, +2.6 pp | | [AIKO AIKO-A640-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a640-mae72mw) | 640 W | Cooler, lighter, +2.6 pp | | [Jinko Solar JKM650-670N-66QL6-BDV (670W class)](https://comparepv.com/panel/jinko-solar-jkm650-670n-66ql6-bdv-670w-class) | 670 W | +50 W, cooler, +2.6 pp | | [DAH Solar DAS-DH156NA-610](https://comparepv.com/panel/dah-solar-das-dh156na-610) | 610 W | -10 W, hotter, -0.4 pp | | [DAH Solar DAS-DH156NA-615](https://comparepv.com/panel/dah-solar-das-dh156na-615) | 615 W | Hotter | | [DAH Solar DHN-78X16/DG-625W](https://comparepv.com/panel/dah-dhn-78x16-dg-625w) | 625 W | Very close match | | [DAH Solar DHN-78X16/DG-630W](https://comparepv.com/panel/dah-dhn-78x16-dg-630w) | 630 W | +10 W, +0.4 pp | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | +60 W, lighter, +3.0 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | +55 W, lighter, +2.8 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | +80 W, cooler, +2.8 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | +75 W, cooler, +2.7 pp | --- Source: https://comparepv.com/panel/dah-dhn-78x16-dg-620w 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.