Panel comparison · July 2026

Two Trina panels both say 515 W. One reaches it on 6% less roof.

A wattage label does not describe how much roof a module occupies, how it responds to heat or how much published evidence sits behind its score. Trinasolar now has two Australian Vertex S+ families whose top bins both read 515 W. The newer Vertex S+ G3 78-cell is the smaller, denser module. The established Vertex S+ NEG18R.25 currently has the deeper criterion-level evidence record.

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Exact Australian datasheets · 515 W top bins

The G3 produces the same nameplate power from less module area

Vertex S+ NEG18R.252.22 m²

1961 × 1134 mm

Vertex S+ G3 78-cell2.09 m²

1842 × 1134 mm

Chart data

Series	Value	Note
Vertex S+ NEG18R.25	2.22 m²	1961 × 1134 mm
Vertex S+ G3 78-cell	2.09 m²	1842 × 1134 mm

The number that changes the roof plan is efficiency

The NEG18R.25 top bin is published at 23.2% efficiency. The G3 reaches 24.65%, a gain of 1.45 percentage points. That difference is why equal nameplate wattage does not mean equal module size. A constrained roof may fit more rated power with the G3, but an installer still has to model setbacks, clamps, wind zones, electrical design and actual array geometry.

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Module efficiency at the scored top bin

The G3 converts more of the same test irradiance into rated output

Vertex S+ NEG18R.2523.2%

490–515 W

Vertex S+ G3 78-cell24.65%

495–515 W

Chart data

Series	Value	Note
Vertex S+ NEG18R.25	23.2%	490–515 W
Vertex S+ G3 78-cell	24.65%	495–515 W

Heat and rear-load ratings separate them again

The G3 publishes a -0.26%/°C Pmax temperature coefficient, compared with -0.29%/°C for the NEG18R.25. At a 40°C cell-temperature rise above STC, that arithmetic equates to approximately 53.6 W of nameplate loss for the G3 and 59.7 W for the older family, a difference of about 6.2 W per 515 W module. This is a controlled comparison, not an annual-yield forecast.

The published rear static-load rating also rises from 2,400 Pa to 4,000 Pa, an increase of 67%. That rating is useful design evidence, but it does not replace site-specific mounting and wind-region engineering.

What stays equal and what does not

The shared 515 W label hides four buying distinctions

1. 01
   Warranty duration

   Both publish 25-year product and 30-year performance terms for the reviewed Australian families.

2. 02
   Cell format

   NEG18R.25 uses 108 half cells, or a 54-cell equivalent. G3 uses 156 half cells, or a 78-cell equivalent, built from smaller cells in a shorter module.

3. 03
   Benchmark score

   The current global scores are 73.2 and 78.4, a 5.2-point gap under the same panel rubric.

4. 04
   Evidence depth

   NEG18R.25 has 69% direct criterion linkage. The newer G3 record has 59%, so its higher score should not be misread as deeper documentation.

Side-by-side buyer reference

Measure	Vertex S+ NEG18R.25	Vertex S+ G3 78-cell
Australian series	490–515 W	495–515 W
Scored top bin	515 W	515 W
Module area	2.22 m²	2.09 m²
Efficiency	23.2%	24.65%
Pmax temperature coefficient	-0.29%/°C	-0.26%/°C
Rear static load	2,400 Pa	4,000 Pa
Product / performance warranty	25 / 30 years	25 / 30 years
Global benchmark score	73.2	78.4
Direct source coverage	69%	59%

The score is global. Australian availability and exact-model evidence are recorded separately. Evidence coverage describes auditability, not product quality.

Use the codes, not only the wattage

The useful identifiers are NEG18R.25 and NEG10R.28Z. They distinguish two different physical products under the same Vertex S+ name and 515 W headline. The G3's 78-cell-equivalent format does not make it a larger panel; it describes how its smaller cells are segmented. Buyers comparing quotes should match the full model family, the exact wattage bin and the supplied warranty document.

Open both products in the comparison tool, inspect the Vertex S+ NEG18R.25 scorecard and Vertex S+ G3 78-cell scorecard, or return to the Australian panel register.

Sources and methodliving dataset

• Trina Solar TSM_AUS_EN_2025_C, 490-515 W, exact NEG18R.25 Australian datasheet.
• Trinasolar TSM_AUS_EN_2026_PA5, NEG10R.28Z 495-515 W, exact NEG10R.28Z Australian datasheet.
• Global scores, source coverage, market status and scorecard links are generated from the current review.solar dataset at build time.
• Module area and the controlled 40°C temperature-rise example are transparent arithmetic from the published dimensions, rated power and temperature coefficients.

This comparison is a publication reference, not a site design or purchase recommendation. Verify the exact supplied model, current approved-module status, warranty conditions and installation engineering before purchase.