--- title: "Tongwei TWMNF-66HD745 vs Tongwei TWMNF-66HD750 - Solar Panel Comparison | ComparePV" description: "Compare Tongwei TWMNF-66HD745 vs Tongwei TWMNF-66HD750 side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/tongwei-solar-twmnf-66hd745/tongwei-solar-twmnf-66hd750" updated: 2026-09-11 --- # Tongwei TWMNF-66HD745 vs Tongwei TWMNF-66HD750 Identical on every published parameter All 19 comparable parameters agree. Two records this alike are usually one panel sold under two names, or two bins of the same production line - decide on price and on who you would rather buy from. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [Tongwei TWMNF-66HD745](https://comparepv.com/panel/tongwei-solar-twmnf-66hd745) | [Tongwei TWMNF-66HD750](https://comparepv.com/panel/tongwei-solar-twmnf-66hd750) | | Manufacturer | Tongwei | Tongwei | | Power | 745 Wp | 750 Wp | | Efficiency | 24.00 % | 24.10 % | | Technology | TOPCon | TOPCon | ## Every compared parameter | Parameter | 66HD745 | 66HD750 | | --- | --- | --- | | Rated power | 745 Wp | 750 Wp | | Module efficiency | 24.00 % | 24.10 % | | Power density | 239.8 Wp/m² | 241.4 Wp/m² | | Open-circuit voltage | 49.95 V | 50.10 V | | Voltage at max power | 41.86 V | 42.02 V | | Short-circuit current | 18.87 A | 18.93 A | | Current at max power | 17.80 A | 17.85 A | | Temperature coefficient | -0.280 %/°C | -0.280 %/°C | | Dimensions | 2384x1303x33 mm | 2384x1303x33 mm | | Module area | 3.106 m² | 3.106 m² | | Weight | 37.3 kg | 37.3 kg | | Weight per kWp | 50.1 kg/kWp | 49.7 kg/kWp | | Product warranty | 12 yrs | 12 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 | 132 | | Bifacial | Yes | Yes | ## Thirty-year yield Each panel's own declared degradation curve, at 1,200 kWh/kWp a year Same temp coeff. for both panels (-0.280 %/°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, 66HD745:** 24,996 kWh - **Cumulative output, 66HD750:** 25,164 kWh - **Gap:** 168 kWh ## Output when hot | Condition | Cell temperature | 66HD745 | 66HD750 | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 745 W | 750 W | 100.0% of rated power | | Cool, bright day | 40 °C | 714 W | 719 W | 95.8% of rated power | | Typical summer roof | 55 °C | 682 W | 687 W | 91.6% of rated power | | Hot roof | 70 °C | 651 W | 656 W | 87.4% of rated power | ## Against the whole database | Measure | 66HD745 | 66HD750 | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #303 | #219 | 14,005 | 66HD750 leads by 84 places | | Power density | #339 | #219 | 14,005 | 66HD750 leads by 120 places | | Heat behaviour | #1,309 | #1,309 | 14,005 | Tied - the same position in the database | | Weight | #3,586 | #3,210 | 14,005 | 66HD750 leads by 376 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #148 | #122 | 14,005 | 66HD750 leads by 26 places | ## Questions ### Which panel is better: Tongwei TWMNF-66HD745 or Tongwei TWMNF-66HD750? According to our database: **Tongwei TWMNF-66HD750** has higher module efficiency (**24.10%** vs **24.00%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of Tongwei TWMNF-66HD745 and Tongwei TWMNF-66HD750? **Tongwei TWMNF-66HD745** has a module efficiency of **24.00%**, while **Tongwei TWMNF-66HD750** is **24.10%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does Tongwei TWMNF-66HD745 use vs Tongwei TWMNF-66HD750? **Tongwei TWMNF-66HD745** uses **TOPCon** cells; **Tongwei TWMNF-66HD750** 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 Tongwei TWMNF-66HD745 and Tongwei TWMNF-66HD750? **Tongwei TWMNF-66HD745** has a **30 years** power warranty; **Tongwei TWMNF-66HD750** 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 Tongwei TWMNF-66HD745 and Tongwei TWMNF-66HD750 bifacial panels? Both **Tongwei TWMNF-66HD745** and **Tongwei TWMNF-66HD750** are bifacial - they capture reflected light from the ground, which can add 5**-15%** more annual energy on ground-mount or elevated rooftop installations with a light surface beneath. ## Related comparisons - [Tongwei TWMNF-66HD745 vs Tongwei TWMNF-66HD740](https://comparepv.com/compare/tongwei-solar-twmnf-66hd745/tongwei-solar-twmnf-66hd740) - One difference: module efficiency - [Tongwei TWMNF-66HD745 vs Tongwei TWMNF-66HD735](https://comparepv.com/compare/tongwei-solar-twmnf-66hd745/tongwei-solar-twmnf-66hd735) - 3 differences, the largest is module efficiency - [Tongwei TWMNF-66HD745 vs Tongwei TWMNF-66HD730](https://comparepv.com/compare/tongwei-solar-twmnf-66hd745/tongwei-solar-twmnf-66hd730) - 3 differences, the largest is module efficiency - [Tongwei TWMNF-66HD745 vs Tongwei TWMHF-66HD740X](https://comparepv.com/compare/tongwei-solar-twmnf-66hd745/tw-solar-twmhf-66hd740x) - 4 differences, the largest is temperature coefficient - [Tongwei TWMNF-66HD745 vs Tongwei THC G12-66 Bifacial](https://comparepv.com/compare/tongwei-solar-twmnf-66hd745/tongwei-thc-g12-66-bifacial) - 2 differences, the largest is product warranty - [Tongwei TWMNF-66HD745 vs Tongwei TWMHF-66HD735X](https://comparepv.com/compare/tongwei-solar-twmnf-66hd745/tw-solar-twmhf-66hd735x) - 7 differences, the largest is temperature coefficient --- Source: https://comparepv.com/compare/tongwei-solar-twmnf-66hd745/tongwei-solar-twmnf-66hd750 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.