--- title: "Solaria Solaria PowerXT-400R-PM vs Solaria Solaria PowerXT-420C-PD - Solar Panel Comparison | ComparePV" description: "Compare Solaria Solaria PowerXT-400R-PM vs Solaria Solaria PowerXT-420C-PD side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/solaria-solaria-powerxt-400r-pm/solaria-solaria-powerxt-420c-pd" updated: 2026-09-11 --- # Solaria Solaria PowerXT-400R-PM vs Solaria Solaria PowerXT-420C-PD 400R-PM leads on the differences that matter The largest is module efficiency: 0.80 pp more efficient. 3 of 16 comparable parameters are identical, with 3 more left out because at least one datasheet does not publish them. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [Solaria Solaria PowerXT-400R-PM](https://comparepv.com/panel/solaria-solaria-powerxt-400r-pm) | [Solaria Solaria PowerXT-420C-PD](https://comparepv.com/panel/solaria-solaria-powerxt-420c-pd) | | Manufacturer | Solaria | Solaria | | Power | 400 Wp | 420 Wp | | Efficiency | 20.20 % | 19.40 % | | Technology | | | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | 400R-PM | 420C-PD | Difference | | --- | --- | --- | --- | | Module efficiency | 20.20 % | 19.40 % | +0.80 pp for 400R-PM | | Performance warranty | 30 yrs | 25 yrs | +5 yrs for 400R-PM | | Weight | 21.0 kg | 29.0 kg | -8.0 kg for 400R-PM | | Weight per kWp | 52.5 kg/kWp | 69.0 kg/kWp | -16.5 kg/kWp for 400R-PM | | Product warranty | 30 yrs | 25 yrs | +5 yrs for 400R-PM | | Power density | 202.1 Wp/m² | 194.1 Wp/m² | +8.0 Wp/m² for 400R-PM | | Rated power | 400 Wp | 420 Wp | +20 W for 420C-PD | | Open-circuit voltage | 51.10 V | 47.10 V | 4.00 V apart | | Module area | 1.979 m² | 2.164 m² | 0.185 m² apart | | Short-circuit current | 9.82 A | 11.39 A | 1.57 A apart | | Voltage at max power | 42.40 V | 38.80 V | 3.60 V apart | | Current at max power | 9.41 A | 10.82 A | 1.41 A apart | | Dimensions | 1644x1204x40 mm | 1939x1116x40 mm | 1644x1204x40 mm vs 1939x1116x40 mm | ## Every compared parameter | Parameter | 400R-PM | 420C-PD | | --- | --- | --- | | Rated power | 400 Wp | 420 Wp | | Module efficiency | 20.20 % | 19.40 % | | Power density | 202.1 Wp/m² | 194.1 Wp/m² | | Open-circuit voltage | 51.10 V | 47.10 V | | Voltage at max power | 42.40 V | 38.80 V | | Short-circuit current | 9.82 A | 11.39 A | | Current at max power | 9.41 A | 10.82 A | | Temperature coefficient | -0.390 %/°C | -0.390 %/°C | | Dimensions | 1644x1204x40 mm | 1939x1116x40 mm | | Module area | 1.979 m² | 2.164 m² | | Weight | 21.0 kg | 29.0 kg | | Weight per kWp | 52.5 kg/kWp | 69.0 kg/kWp | | Product warranty | 30 yrs | 25 yrs | | Performance warranty | 30 yrs | 25 yrs | | Annual degradation | 0.48 %/yr | - | | Cell technology | - | - | | Cell type | Monocrystalline | Monocrystalline | | Cell count | - | - | | Bifacial | No | No | ## Thirty-year yield A 1.0% first-year loss then 0.40% a year, assumed for both panels, at 1,200 kWh/kWp a year Same temp coeff. for both panels (-0.390 %/°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, 400R-PM:** 13,421 kWh - **Cumulative output, 420C-PD:** 14,092 kWh - **Gap:** 671 kWh ## Output when hot | Condition | Cell temperature | 400R-PM | 420C-PD | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 400 W | 420 W | 100.0% of rated power | | Cool, bright day | 40 °C | 377 W | 395 W | 94.2% of rated power | | Typical summer roof | 55 °C | 353 W | 371 W | 88.3% of rated power | | Hot roof | 70 °C | 330 W | 346 W | 82.5% of rated power | ## Against the whole database | Measure | 400R-PM | 420C-PD | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #11,956 | #12,735 | 14,005 | 400R-PM leads by 779 places | | Power density | #11,987 | #12,726 | 14,005 | 400R-PM leads by 739 places | | Heat behaviour | #13,579 | #13,579 | 14,005 | Tied - the same position in the database | | Weight | #6,043 | #13,359 | 14,005 | 400R-PM leads by 7,316 places | | Warranty | #21 | #9,798 | 14,005 | 400R-PM leads by 9,777 places | | Overall | #9,549 | #11,183 | 14,005 | 400R-PM leads by 1,634 places | ## Questions ### Which panel is better: Solaria Solaria PowerXT-400R-PM or Solaria Solaria PowerXT-420C-PD? According to our database: **Solaria **Solaria** PowerXT-400R-PM** has higher module efficiency (**20.20%** vs **19.40%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of Solaria Solaria PowerXT-400R-PM and Solaria Solaria PowerXT-420C-PD? **Solaria **Solaria** PowerXT-400R-PM** has a module efficiency of **20.20%**, while **Solaria **Solaria** PowerXT-420C-PD** is **19.40%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does Solaria Solaria PowerXT-400R-PM use vs Solaria Solaria PowerXT-420C-PD? **Solaria **Solaria** PowerXT-400R-PM** uses Monocrystalline cells; **Solaria **Solaria** PowerXT-420C-PD** uses Monocrystalline. 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 Solaria Solaria PowerXT-400R-PM and Solaria Solaria PowerXT-420C-PD? **Solaria **Solaria** PowerXT-400R-PM** has a **30 years** power warranty; **Solaria **Solaria** PowerXT-420C-PD** has a **25 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. ## Related comparisons - [Solaria Solaria PowerXT-400R-PM vs Solaria PowerXT 430R-PL](https://comparepv.com/compare/solaria-solaria-powerxt-400r-pm/solaria-powerxt-430r-pl) - 9 differences, the largest is rated power - [Solaria Solaria PowerXT-400R-PM vs Solaria Solaria PowerXT-430C-PD](https://comparepv.com/compare/solaria-solaria-powerxt-400r-pm/solaria-solaria-powerxt-430c-pd) - 13 differences, the largest is performance warranty - [Solaria Solaria PowerXT-400R-PM vs Solaria PowerXT 420R-PL](https://comparepv.com/compare/solaria-solaria-powerxt-400r-pm/solaria-powerxt-420r-pl) - 9 differences, the largest is rated power - [Solaria Solaria PowerXT-400R-PM vs Solaria Solaria PowerXT-420C-BD](https://comparepv.com/compare/solaria-solaria-powerxt-400r-pm/solaria-solaria-powerxt-420c-bd) - 13 differences, the largest is module efficiency - [Solaria Solaria PowerXT-400R-PM vs Solaria Solaria PowerXT-410C-BD](https://comparepv.com/compare/solaria-solaria-powerxt-400r-pm/solaria-solaria-powerxt-410c-bd) - 13 differences, the largest is module efficiency - [Solaria Solaria PowerXT-400R-PM vs Solaria Solaria PowerX-400R](https://comparepv.com/compare/solaria-solaria-powerxt-400r-pm/solaria-solaria-powerx-400r) - 12 differences, the largest is performance warranty --- Source: https://comparepv.com/compare/solaria-solaria-powerxt-400r-pm/solaria-solaria-powerxt-420c-pd 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.