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DMEGC DM620G12RT-B66HSW
DMEGC Brand review

DM620G12RT-B66HSW

620 Wp TOPCon Bifacial 80%
ComparePV verdict

Solid all-round for its segment

Rank 2,023 of 14,005
Compare panels Datasheet PDF
Power (Wp)
620
Typical for its class
Efficiency (%)
23.00
Typical · median 22.80%
Density (Wp/m²)
229.5
Typical · median 227.7
Temp (%/°C)
-0.290
Typical · median -0.290
Weight (kg)
32.3
Typical · median 32.7 kg
Warranty (yrs)
30
Typical · median 30 yrs

The DMEGC DMxxxG12RT-B66HSW module series defines a new standard of efficiency thanks to the use of innovative N-type TOPCon cells in a rectangular format. The use of G12RT rectangular cell technology allows for much denser silicon packing within the frame, which directly translates into higher efficiency without the need to increase the panel dimensions. The bifacial double glass design, based on dual glass, eliminates the risk of micro-cracks and guarantees extreme resistance to degradation caused by moisture or ammonia. This solves the problem of long-term power loss, offering investors full financial security. A key differentiator is the low temperature coefficient, which makes the panels work more effectively in full sun than traditional P-type solutions. This series is dedicated to demanding residential installations and large-scale commercial projects, where maximizing yields from every square meter of roof or ground is essential. Thanks to high resistance to mechanical loads, the modules handle heavy snow and strong winds perfectly, which sets them apart from competitors offering less rigid structures. Choosing this series is an investment in energy stability and the technology of tomorrow, which effectively minimizes transmission losses and optimizes cooperation with modern inverters.

Ranking

1,086 panels in the segment TOPCon 600-650 W
Metric This panel Median Position in segment Overall rank
Module efficiency 23.00% 22.80% Typical 1,919
Power density 229.5 227.7 Typical 2,191
Temperature coefficient -0.290 -0.290 Typical 2,165
Weight per kWp 52.1 53.1 Typical 5,543
Performance warranty 30 yrs 30 yrs Typical 21
Colour key Strong - top 25% Typical - middle 50% Weak - bottom 25%

Signals from the data

5 positive · 1 caution
Best for

Residential, commercial, utility-scale and hot-climate.

What owners get
Low temperature coefficient: -0.29%/°C

A Pmax temperature coefficient of -0.29%/°C is notably more favorable than the typical range for P-type PERC modules (-0.34 to -0.36%/°C). Under Polish summer conditions—with module temperatures reaching 60–70°C—this translates to a real-world energy yield gain of 2–4% compared to older technology.

Up to 23% efficiency – top of the segment

The 620 Wp variant achieves 23% module efficiency, matching direct competitors (HT-SAAE HT66-18X(ND)-F: 23%, Weran Solar LR7-72HTH: 23%). The G12RT rectangular cell technology with 16BB and SMBB interconnection (132 half-cut cells) maximizes active silicon area within a 2382×1134 mm frame.

Bifacial double glass with 80±5% bifaciality

Dual tempered glass (2 mm) eliminates the risk of PID, microcracks, and degradation caused by moisture or ammonia. A bifaciality factor of 80±5% means that at ground albedo of 20–30%, the module generates a real-world 8–12% more energy than a monofacial equivalent—at no additional cost in roof area.

Low degradation: ≤0.4%/year, ≥87.4% after 30 years

The guaranteed linear power degradation of ≤1% in year 1 and ≤0.4%/year in subsequent years ensures a minimum of 87.4% of rated power after 30 years of operation. This figure is on par with leading Tier-1 manufacturers and is critical for IRR calculations in commercial projects with a 25+ year horizon.

BNEF Tier 1 + Kiwa PVEL Top Performer 2025

DMEGC has maintained BloombergNEF Tier-1 status for at least 6 consecutive years (confirmed in the Q3 2025 ranking), ensuring bankability for externally financed projects. Independent Kiwa PVEL testing (Scorecard 2025) confirms above-average module reliability across mechanical stress and environmental test sequences.

Trade-offs
Product warranty of only 15 years

The product warranty (covering defects and physical damage) is 15 years, while leading Tier-1 manufacturers in this segment (LONGi, JA Solar, Canadian Solar, Trina Solar) standardly offer 25–30 years. For projects financed with bank debt carrying a 20+ year repayment period, this may be an eliminating criterion or require additional insurance coverage.

Notes from the database
  • At 23.0% efficiency, this panel is on par with typical TOPCon 600-650W modules
  • At 229.5 W/m² power density, roof space requirements are typical for TOPCon 600-650W panels
  • Temperature coefficient of -0.29%/°C matches the TOPCon 600-650W median
  • Bifaciality factor of 80% can add 4-12% extra yield with reflective mounting surface
  • #1919 for efficiency, #2165 for temperature performance out of 14005 panels

Specifications

Open datasheet PDF
Nominal power (Pmax) 620 Wp Nameplate at 1000 W/m², 25 °C
Module efficiency 23.00 % Typical Segment median 22.80%
Vmpp · Impp 40.85 V · 15.20 A Operating point at max power
Voc · Isc 49.09 V · 16.11 A Sizes the string length
Max system voltage 1500 V Longer strings than 1000 V modules
Dimensions 2382×1134×30 mm · 2.70 m² of roof
Weight 32.3 kg Typical Typical · median 32.7 kg
Cells 132 · TOPCon Monocrystalline
Bifaciality 80 % Rear output as a share of front
Coefficient Pmax -0.290 %/°C Typical median -0.290 of its segment
Coefficient Voc · Isc -0.250 · 0.048 %/°C
NOCT 42 °C At 800 W/m², 20 °C ambient
Product warranty 15 years Hardware defects only
Performance warranty 30 years Typical median 30 yrs · median 30 yrs
End-of-warranty output 87.4 % Equals 542 W guaranteed
Degradation 1.00 → 0.40 % First year, then annual

Datasheet charts

Open datasheet PDF

Measured curves published by DMEGC in this model's datasheet. A chart carrying a wattage was measured on that variant alone - only the ones that describe 620 Wp appear here. The rest cover the whole series.

Current-Voltage Curve (620W) Current-Voltage Curve (620W) 620 W

Simulations

Live - change any input
Lifetime output & value
30 years at 1200 kWh/kWp/year and €0.50 per kWh
Power in year 30
-
Lifetime energy
-
Energy value
-
With bifacial gain
-

Degradation from this panel's own datasheet figures. No inverter, soiling or shading losses.

Heat losses
-0.290 %/°C against a segment median of -0.290
-
Bifacial gain
Rear gain over light concrete: -
-

Model: bifaciality × albedo × 0.6 view factor. A first-order estimate, not a yield simulation.

Filter these
Size
Panel Power Eff. Temp. Weight Difference
DMEGC DM620G12RT-B66HSW 620 W 23.00% -0.290 32.3 kg You are here
AIKO-A650-MAE72Mw 650 W 25.20% -0.260 27.0 kg +30 W, lighter, +2.2 pp
AIKO-A645-MAE72Mw 645 W 25.00% -0.260 27.0 kg Cooler, lighter, +2.0 pp
AIKO-G670-MCH72Mw 670 W 24.80% -0.260 28.2 kg +50 W, lighter, +1.8 pp
LR7-72HVHF-670M 670 W 24.80% -0.260 28.5 kg +50 W, lighter, +1.8 pp
AIKO-A640-MAE72Mw 640 W 24.80% -0.260 27.0 kg Cooler, lighter, +1.8 pp
JKM650-670N-66QL6-BDV (670W class) 670 W 24.80% -0.260 32.5 kg +50 W, cooler, +1.8 pp
DM605G12RT-B66HSW 605 W 22.40% -0.290 32.3 kg -15 W, -0.6 pp
DM610G12RT-B66HSW 610 W 22.60% -0.290 32.3 kg -10 W, -0.4 pp
DM615G12RT-B66HSW 615 W 22.80% -0.290 32.3 kg Very close match
DM625G12RT-B66HSW 625 W 23.10% -0.290 32.3 kg Very close match
DM630G12RT-B66HSW 630 W 23.30% -0.290 32.3 kg +10 W, +0.3 pp
DM635G12RT-B66HSW 635 W 23.50% -0.290 32.3 kg +15 W, +0.5 pp
AIKO-A680-MDE72Mw 680 W 25.20% -0.260 29.0 kg +60 W, lighter, +2.2 pp
AIKO-A675-MDE72Mw 675 W 25.00% -0.260 29.0 kg +55 W, lighter, +2.0 pp
AIKO-A700-MAE78Dw 700 W 25.00% -0.260 34.5 kg +80 W, cooler, +2.0 pp
AIKO-A695-MAE78Dw 695 W 24.90% -0.260 34.5 kg +75 W, cooler, +1.9 pp

Found 1119 panels of the same or similar size to this one, within ±10 mm. See them here Found 1125 panels of the same or similar size to this one, within ±25 mm. See them here Found 1236 panels of the same or similar size to this one, within ±50 mm. See them here Found 1917 panels of the same or similar size to this one, within ±100 mm. See them here

Common questions

6 answered
What warranty covers the DMEGC DMxxxG12RT-B66HSW panels and what exactly does it include?
The DMxxxG12RT-B66HSW series is backed by a 15-year product warranty covering manufacturing defects and workmanship, along with a 30-year linear power output warranty. In practical terms, this means the panel is guaranteed to retain at least 87.4% of its nominal power after 30 years, with an annual degradation rate not exceeding 0.4% and no more than 1% in the first year. This is one of the longest warranty packages in the industry and reflects the manufacturer's confidence in the durability of N-type TOPCon technology.
Is the DMEGC DMxxxG12RT-B66HSW suitable for rooftop installations with partial shading or for ground-mounted systems?
Yes. The bifacial double-glass construction with G12RT cells allows the module to harvest energy from both the front and rear sides (bifaciality factor of approximately 80%), which is especially advantageous in ground-mounted systems with light-colored surfaces or gravel substrates. For rooftop installations subject to partial shading, the choice of an appropriate inverter or power optimizers is critical, as the module itself does not include built-in microinverters.
How do G12RT cells differ from standard G12 cells in solar panels?
G12RT cells have a rectangular format, as opposed to the square shape of conventional G12 cells. This geometry allows for denser packing within a module frame of identical external dimensions, reducing inactive surface area. The result is a higher module efficiency of up to 23.5–24.4% within the same footprint, which directly translates into more kilowatt-hours per square meter of installed capacity.
How does the DMEGC DMxxxG12RT-B66HSW 620 Wp panel perform on hot days when temperatures exceed 35°C?
N-type TOPCon technology features a low temperature coefficient for Pmax of approximately -0.30%/°C. This means that at a cell temperature of, for example, 65°C — typical during summer — the panel loses around 12% of its rated power output, whereas older P-type panels typically lose 13–15% under the same conditions. Over the course of a year, this translates into measurably higher energy yields at no additional cost.
Are the DMEGC DMxxxG12RT-B66HSW modules rated for snow loads and high wind pressure under Polish climatic conditions?
Yes. The double-glass construction — consisting of two panes of 2 mm tempered glass — provides excellent mechanical strength. According to manufacturer specifications, the panels are rated for a snow load of up to 5,400 Pa and a wind pressure of up to 2,400 Pa, meeting the standards applicable in Poland including mountainous regions. The absence of a rear backsheet also eliminates the risk of delamination caused by large fluctuations in humidity.
Is DMEGC a reputable manufacturer and are the DMxxxG12RT-B66HSW panels available on the market?
DMEGC Solar is a Chinese manufacturer ranked as a Tier 1 supplier according to the BNEF bankability list, which confirms both financial credibility and verified manufacturing quality. The DMxxxG12RT-B66HSW series is currently in active production and available through distributors in Poland and across Europe. The manufacturer regularly updates the power range of the series — from 610 Wp to 665 Wp depending on the variant — so it is advisable to confirm the availability of a specific model with your supplier before placing an order.
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