The assessment
How it scores, by category
The data
Performance guarantee: 25-year linear output
Wattage figure based on the sourced rated power (420 W) applied to the guaranteed floor; modular/format differences aside, this is the same rated-power spec shown above.
Modelled effective output, year by year
Year 1 to year 25, at 30°C and 1000 W/m². Rated 420 W at STC.
How this is modelled
Compounds this panel’s own published first-year (2%) and annual (0.45%/yr) degradation figures against its 420 W rated (STC) output, then derates for the ambient and irradiance selected. Output is scaled roughly linearly with irradiance (1000W/m² against the 1000 W/m² STC reference). This is the dominant real-world effect at low light, whether from cloud, shading or soiling. Output is then further derated for heat, from this panel’s own NOCT (43°C) and temperature coefficient (-0.34%/°C), giving an estimated cell temperature of 59°C at that ambient and irradiance. A datasheet-derived estimate, not a field measurement or a warranty guarantee: it does not account for this panel’s own low-light efficiency response (a separate, less-consistently-published spec), or for wind and system design. See NOCT and temperature coefficient in the glossary.
Control panel
| Year | 1 | 5 | 10 | 15 | 20 | 25 |
|---|---|---|---|---|---|---|
| Watts | 364 W | 358 W | 349 W | 341 W | 333 W | 324 W |
| % of rated | 86.8% | 85.2% | 83.2% | 81.2% | 79.2% | 77.2% |
Two things to check
Ask the installer: Will the quote name the exact TSP 420 model and wattage, and who covers labour if the module warranty is used?
Verification & sources
Market context
Global benchmark. This scorecard is benchmarked globally. A global score does not imply local availability, certification, warranty coverage, or installer compatibility.
Benchmark anchor. The score is anchored to the highest published rating in this exact published US series. Scored model: TSP-420 · checked 2026-07-16. Evidence.
Sources & references · checked 2026-07-14
Moderate evidence coverage
13 of 26 scored criteria link directly to a published source.
Values marked estimated, derived, or not found remain visible on the audit sheet and do not carry the same evidential weight as a linked source. Coverage measures direct links, not an independent guarantee that a claim is correct.
- Sourced valuesData card →
- Warranty summary25-year product warranty →
Help strengthen this record
These are published evidence gaps, not private submissions. A source is reviewed under the same methodology whether it comes from a reader, installer or manufacturer.
- Encapsulation & frame constructionThe current record is estimated. A primary or independent source is requested.Offer a source
- ContactThe current record is estimated. A primary or independent source is requested.Offer a source
- AwardsThe current record is estimated. A primary or independent source is requested.Offer a source
- Independent energy yieldThe current record is estimated. A primary or independent source is requested.Offer a source
Evidence timeline
Recorded verification events for this scorecard. These are evidence checks, not historical score snapshots.
- Series benchmark source checked
- US market evidence checked
- Core scorecard evidence checked
- AU market evidence checked
- Plain-language warranty summary checked
Scored by Solar Analytica Research
Further reading from Signals
Stay across the benchmark.
New scorecards, score changes and market signals, published as they happen.
Our reading
Its strongest scoring dimension is guarantee & backbone (70). Efficiency & Yield (48) is the dimension with the most room to move. Underlying specifications include a module efficiency of 20.5%, 25-year product warranty backed by a 25-year performance term.