--- title: "HT-SAAE HT66-18X(N)-630W vs HT-SAAE HT66-18X(ND)-F 620W - Solar Panel Comparison | ComparePV" description: "Compare HT-SAAE HT66-18X(N)-630W vs HT-SAAE HT66-18X(ND)-F 620W side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/ht-saae-ht66-18x-n-630w/ht-saae-ht66-18x-nd-f-620w" image: "https://comparepv.com/og/compare/panels/ht-saae-ht66-18x-n-630w/ht-saae-ht66-18x-nd-f-620w.png" updated: 2026-09-11 --- # HT-SAAE HT66-18X(N)-630W vs HT-SAAE HT66-18X(ND)-F 620W 18X(N)-630W leads on the differences that matter The largest is weight: 4.5 kg lighter. 13 of 19 comparable parameters are identical. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [HT-SAAE HT66-18X(N)-630W](https://comparepv.com/panel/ht-saae-ht66-18x-n-630w) | [HT-SAAE HT66-18X(ND)-F 620W](https://comparepv.com/panel/ht-saae-ht66-18x-nd-f-620w) | | Manufacturer | HT-SAAE | HT-SAAE | | Power | 630 Wp | 620 Wp | | Efficiency | 23.30 % | 23.00 % | | Technology | TOPCon | TOPCon | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | 18X(N)-630W | 18X(ND)-F 620W | Difference | | --- | --- | --- | --- | | Weight | 29.0 kg | 33.5 kg | -4.5 kg for 18X(N)-630W | | Weight per kWp | 46.0 kg/kWp | 54.0 kg/kWp | -8.0 kg/kWp for 18X(N)-630W | | Module efficiency | 23.30 % | 23.00 % | +0.30 pp for 18X(N)-630W | | Power density | 233.2 Wp/m² | 229.5 Wp/m² | +3.7 Wp/m² for 18X(N)-630W | | Rated power | 630 Wp | 620 Wp | +10 W for 18X(N)-630W | | Bifacial | No | Yes | No vs Yes | ## Every compared parameter | Parameter | 18X(N)-630W | 18X(ND)-F 620W | | --- | --- | --- | | Rated power | 630 Wp | 620 Wp | | Module efficiency | 23.30 % | 23.00 % | | Power density | 233.2 Wp/m² | 229.5 Wp/m² | | Open-circuit voltage | 48.70 V | 48.30 V | | Voltage at max power | 40.60 V | 40.20 V | | Short-circuit current | 16.25 A | 16.15 A | | Current at max power | 15.53 A | 15.43 A | | Temperature coefficient | -0.310 %/°C | -0.310 %/°C | | Dimensions | 2382x1134x35 mm | 2382x1134x35 mm | | Module area | 2.701 m² | 2.701 m² | | Weight | 29.0 kg | 33.5 kg | | Weight per kWp | 46.0 kg/kWp | 54.0 kg/kWp | | Product warranty | 30 yrs | 30 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 | No | Yes | ## Thirty-year yield Declared annual degradation, with a 1.0% first-year loss assumed for both panels because at least one datasheet omits it, at 1,200 kWh/kWp a year Same temp coeff. for both panels (-0.310 %/°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, 18X(N)-630W:** 21,138 kWh - **Cumulative output, 18X(ND)-F 620W:** 20,802 kWh - **Gap:** 336 kWh ## Output when hot | Condition | Cell temperature | 18X(N)-630W | 18X(ND)-F 620W | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 630 W | 620 W | 100.0% of rated power | | Cool, bright day | 40 °C | 601 W | 591 W | 95.3% of rated power | | Typical summer roof | 55 °C | 571 W | 562 W | 90.7% of rated power | | Hot roof | 70 °C | 542 W | 534 W | 86.0% of rated power | ## Against the whole database | Measure | 18X(N)-630W | 18X(ND)-F 620W | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #1,057 | #1,970 | 14,129 | 18X(N)-630W leads by 913 places | | Power density | #1,042 | #2,243 | 14,129 | 18X(N)-630W leads by 1,201 places | | Heat behaviour | #8,069 | #8,069 | 14,129 | Tied - the same position in the database | | Weight | #963 | #8,326 | 14,129 | 18X(N)-630W leads by 7,363 places | | Warranty | #21 | #21 | 14,129 | Tied - the same position in the database | | Overall | #294 | #538 | 14,129 | 18X(N)-630W leads by 244 places | ## Questions ### Which panel is better: HT-SAAE HT66-18X(N)-630W or HT-SAAE HT66-18X(ND)-F 620W? According to our database: **HT-SAAE HT66-18X(N)-**630 W**** has higher module efficiency (**23.30%** vs **23.00%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of HT-SAAE HT66-18X(N)-630W and HT-SAAE HT66-18X(ND)-F 620W? **HT-SAAE HT66-18X(N)-**630 W**** has a module efficiency of **23.30%**, while **HT-SAAE HT66-18X(ND)-F **620 W**** is **23.00%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does HT-SAAE HT66-18X(N)-630W use vs HT-SAAE HT66-18X(ND)-F 620W? **HT-SAAE HT66-18X(N)-**630 W**** uses **TOPCon** cells; **HT-SAAE HT66-18X(ND)-F **620 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 HT-SAAE HT66-18X(N)-630W and HT-SAAE HT66-18X(ND)-F 620W? **HT-SAAE HT66-18X(N)-**630 W**** has a **30 years** power warranty; **HT-SAAE HT66-18X(ND)-F **620 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 HT-SAAE HT66-18X(N)-630W and HT-SAAE HT66-18X(ND)-F 620W bifacial panels? **HT-SAAE HT66-18X(ND)-F **620 W**** is bifacial (captures light from both faces); **HT-SAAE HT66-18X(N)-**630 W**** is monofacial. Bifacial panels work best on ground mounts or raised structures with a light-coloured surface underneath. ## Related comparisons - [HT-SAAE HT66-18X(N)-630W vs HT-SAAE HT66-18X(N)-625W](https://comparepv.com/compare/ht-saae-ht66-18x-n-630w/ht-saae-ht66-18x-n-625w) - One difference: module efficiency - [HT-SAAE HT66-18X(N)-630W vs HT-SAAE HT66-18X(N)-620W](https://comparepv.com/compare/ht-saae-ht66-18x-n-630w/ht-saae-ht66-18x-n-620w) - 3 differences, the largest is module efficiency - [HT-SAAE HT66-18X(N)-630W vs HT-SAAE HT66-18X(ND)-F-620](https://comparepv.com/compare/ht-saae-ht66-18x-n-630w/ht-saae-ht66-18x-nd-f-620) - 6 differences, the largest is weight - [HT-SAAE HT66-18X(N)-630W vs HT-SAAE HT66-18X(ND)-F 615W](https://comparepv.com/compare/ht-saae-ht66-18x-n-630w/ht-saae-ht66-18x-nd-f-615w) - 6 differences, the largest is module efficiency - [HT-SAAE HT66-18X(N)-630W vs HT-SAAE HT66-18X(N)-615W](https://comparepv.com/compare/ht-saae-ht66-18x-n-630w/ht-saae-ht66-18x-n-615w) - 3 differences, the largest is module efficiency - [HT-SAAE HT66-18X(N)-630W vs HT-SAAE HT66-18X(ND)-F-615](https://comparepv.com/compare/ht-saae-ht66-18x-n-630w/ht-saae-ht66-18x-nd-f-615) - 6 differences, the largest is module efficiency --- Source: https://comparepv.com/compare/ht-saae-ht66-18x-n-630w/ht-saae-ht66-18x-nd-f-620w 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.