--- title: "Trina Solar TSM-NEG21C.20-735 vs Trina Solar TSM-NEG9R.28 455W - Solar Panel Comparison | ComparePV" description: "Compare Trina Solar TSM-NEG21C.20-735 vs Trina Solar TSM-NEG9R.28 455W side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/trina-solar-co-ltd-tsm-neg21c-20-735/trina-solar-co-ltd-tsm-neg9r-28-455w-1" updated: 2026-09-11 --- # Trina Solar TSM-NEG21C.20-735 vs Trina Solar TSM-NEG9R.28 455W NEG21C.20-735 leads on the differences that matter The largest is module efficiency: 0.90 pp more efficient. 5 of 19 comparable parameters are identical. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [Trina Solar TSM-NEG21C.20-735](https://comparepv.com/panel/trina-solar-co-ltd-tsm-neg21c-20-735) | [Trina Solar TSM-NEG9R.28 455W](https://comparepv.com/panel/trina-solar-co-ltd-tsm-neg9r-28-455w-1) | | Manufacturer | Trina Solar | Trina Solar | | Power | 735 Wp | 455 Wp | | Efficiency | 23.70 % | 22.80 % | | Technology | TOPCon | TOPCon | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | NEG21C.20-735 | NEG9R.28 455W | Difference | | --- | --- | --- | --- | | Module efficiency | 23.70 % | 22.80 % | +0.90 pp for NEG21C.20-735 | | Rated power | 735 Wp | 455 Wp | +280 W for NEG21C.20-735 | | Weight | 38.3 kg | 21.0 kg | -17.3 kg for NEG9R.28 455W | | Power density | 236.6 Wp/m² | 227.7 Wp/m² | +8.9 Wp/m² for NEG21C.20-735 | | Product warranty | 12 yrs | 15 yrs | +3 yrs for NEG9R.28 455W | | Weight per kWp | 52.1 kg/kWp | 46.2 kg/kWp | -6.0 kg/kWp for NEG9R.28 455W | | Short-circuit current | 18.62 A | 10.77 A | 7.85 A apart | | Module area | 3.106 m² | 1.998 m² | 1.108 m² apart | | Open-circuit voltage | 50.10 V | 53.40 V | 3.30 V apart | | Current at max power | 17.55 A | 10.11 A | 7.44 A apart | | Cell count | 132 | 144 | 12 cells apart | | Voltage at max power | 41.90 V | 45.00 V | 3.10 V apart | | Bifacial | Yes | No | Yes vs No | | Dimensions | 2384x1303x33 mm | 1762x1134x30 mm | 2384x1303x33 mm vs 1762x1134x30 mm | ## Every compared parameter | Parameter | NEG21C.20-735 | NEG9R.28 455W | | --- | --- | --- | | Rated power | 735 Wp | 455 Wp | | Module efficiency | 23.70 % | 22.80 % | | Power density | 236.6 Wp/m² | 227.7 Wp/m² | | Open-circuit voltage | 50.10 V | 53.40 V | | Voltage at max power | 41.90 V | 45.00 V | | Short-circuit current | 18.62 A | 10.77 A | | Current at max power | 17.55 A | 10.11 A | | Temperature coefficient | -0.290 %/°C | -0.290 %/°C | | Dimensions | 2384x1303x33 mm | 1762x1134x30 mm | | Module area | 3.106 m² | 1.998 m² | | Weight | 38.3 kg | 21.0 kg | | Weight per kWp | 52.1 kg/kWp | 46.2 kg/kWp | | Product warranty | 12 yrs | 15 yrs | | Performance warranty | 30 yrs | 30 yrs | | Annual degradation | 0.40 %/yr | 0.40 %/yr | | Cell technology | TOPCon | TOPCon | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 132 | 144 | | Bifacial | Yes | No | ## Thirty-year yield Each panel's own declared degradation curve, at 1,200 kWh/kWp a year Same temp coeff. for both panels (-0.290 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other. - **Cumulative output, NEG21C.20-735:** 24,661 kWh - **Cumulative output, NEG9R.28 455W:** 15,266 kWh - **Gap:** 9,395 kWh ## Output when hot | Condition | Cell temperature | NEG21C.20-735 | NEG9R.28 455W | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 735 W | 455 W | 100.0% of rated power | | Cool, bright day | 40 °C | 703 W | 435 W | 95.7% of rated power | | Typical summer roof | 55 °C | 671 W | 415 W | 91.3% of rated power | | Hot roof | 70 °C | 639 W | 396 W | 87.0% of rated power | ## Against the whole database | Measure | NEG21C.20-735 | NEG9R.28 455W | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #517 | #2,714 | 14,005 | NEG21C.20-735 leads by 2,197 places | | Power density | #582 | #2,888 | 14,005 | NEG21C.20-735 leads by 2,306 places | | Heat behaviour | #2,165 | #2,165 | 14,005 | Tied - the same position in the database | | Weight | #5,576 | #1,016 | 14,005 | NEG9R.28 455W leads by 4,560 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #233 | #7,730 | 14,005 | NEG21C.20-735 leads by 7,497 places | ## Questions ### Which panel is better: Trina Solar TSM-NEG21C.20-735 or Trina Solar TSM-NEG9R.28 455W? According to our database: **Trina Solar TSM-NEG21C.20-735** has higher module efficiency (**23.70%** vs **22.80%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of Trina Solar TSM-NEG21C.20-735 and Trina Solar TSM-NEG9R.28 455W? **Trina Solar TSM-NEG21C.20-735** has a module efficiency of **23.70%**, while **Trina Solar TSM-NEG9R.28 **455 W**** is **22.80%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does Trina Solar TSM-NEG21C.20-735 use vs Trina Solar TSM-NEG9R.28 455W? **Trina Solar TSM-NEG21C.20-735** uses **TOPCon** cells; **Trina Solar TSM-NEG9R.28 **455 W**** uses **TOPCon**. Modern **n-type** technologies (**TOPCon**, **HJT**, BC) typically deliver higher efficiency and lower degradation compared to older **PERC** (p-type) cells. ### What is the warranty on Trina Solar TSM-NEG21C.20-735 and Trina Solar TSM-NEG9R.28 455W? **Trina Solar TSM-NEG21C.20-735** has a **30 years** power warranty; **Trina Solar TSM-NEG9R.28 **455 W**** has a **30 years** power warranty. The power warranty guarantees a minimum percentage of rated output at the end of the warranty period (typically 80**-87%**). Product (materials) warranties are usually shorter. ### Are Trina Solar TSM-NEG21C.20-735 and Trina Solar TSM-NEG9R.28 455W bifacial panels? **Trina Solar TSM-NEG21C.20-735** is bifacial (captures light from both faces); **Trina Solar TSM-NEG9R.28 **455 W**** is monofacial. Bifacial panels work best on ground mounts or raised structures with a light-coloured surface underneath. ## Related comparisons - [Trina Solar TSM-NEG21C.20-735 vs Trina Solar TSM-NEG21C.20-740](https://comparepv.com/compare/trina-solar-co-ltd-tsm-neg21c-20-735/trina-solar-co-ltd-tsm-neg21c-20-740) - The same specification on paper - [Trina Solar TSM-NEG21C.20-735 vs Trina Solar TSM-NEG21C.20-730](https://comparepv.com/compare/trina-solar-co-ltd-tsm-neg21c-20-735/trina-solar-co-ltd-tsm-neg21c-20-730) - One difference: module efficiency - [Trina Solar TSM-NEG21C.20-735 vs Trina Solar TSM-NEG21C.20-725](https://comparepv.com/compare/trina-solar-co-ltd-tsm-neg21c-20-735/trina-solar-co-ltd-tsm-neg21c-20-725) - 3 differences, the largest is module efficiency - [Trina Solar TSM-NEG21C.20-735 vs Trina Solar TSM-NEG21C.20-720](https://comparepv.com/compare/trina-solar-co-ltd-tsm-neg21c-20-735/trina-solar-co-ltd-tsm-neg21c-20-720) - 3 differences, the largest is module efficiency - [Trina Solar TSM-NEG21C.20-735 vs Trina Solar TSM-NEG21C.20-715](https://comparepv.com/compare/trina-solar-co-ltd-tsm-neg21c-20-735/trina-solar-co-ltd-tsm-neg21c-20-715) - 3 differences, the largest is module efficiency - [Trina Solar TSM-NEG9R.28 455W vs Trina Solar TSM-470NED9R.28](https://comparepv.com/compare/trina-solar-co-ltd-tsm-neg9r-28-455w-1/trina-solar-tsm-470ned9r-28) - 8 differences, the largest is module efficiency --- Source: https://comparepv.com/compare/trina-solar-co-ltd-tsm-neg21c-20-735/trina-solar-co-ltd-tsm-neg9r-28-455w-1 Not in this file, on the page: the thirty-year yield curve year by year at a cell temperature you pick and a written summary generated on request.