--- title: "Suntech STP390S-C54/Umh Solar Panel: Specs & Datasheet | ComparePV" description: "Suntech STP390S-C54/Umh solar panel. Specs: 19.90% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/suntech-stp390s-c54-umh" image: "https://comparepv.com/og/panel/suntech-stp390s-c54-umh.png" updated: 2026-09-11 --- # Suntech STP390S-C54/Umh Middle of its segment, weak in heat 6,261 panels in the 290-490 W band, all technologies ## Identity - **Manufacturer:** Suntech - **Model:** STP390S-C54/Umh - **Series:** Ultra V mini - **Rated power:** 390 W - **Cell technology:** Monocrystalline ## How it compares Compared against 290-490 W band, all technologies (6261 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 390 W | 430 W | Weak - bottom 20% | | | Module efficiency | 19.90% | 21.25% | Weak - bottom 19% | 12,416 | | Power density | 199.5 | 212.5 | Weak - bottom 20% | 12,376 | | Temperature coefficient | -0.360 | -0.300 | Weak - bottom 12% | 12,425 | | Weight (kg) | 22.1 kg | 22.3 kg | Typical | | | Performance warranty | 25 yrs | 30 yrs | Weak - bottom 19% | 9,912 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 19.90% | 21.25% | Weak - bottom 19% | 12,416 | | Power density | 199.5 | 212.5 | Weak - bottom 20% | 12,376 | | Temperature coefficient | -0.360 | -0.300 | Weak - bottom 12% | 12,425 | | Weight per kWp | 56.7 | 53.3 | Typical | 10,887 | | Performance warranty | 25 yrs | 30 yrs | Weak - bottom 19% | 9,912 | ### Watch out for - **-0.360 %/°C temperature coefficient** - Bottom 12% of the 290-490 W band, against a median of -0.300. - **19.90% module efficiency** - Bottom 19% of the 290-490 W band, against a median of 21.25%. - **25 year performance warranty** - Bottom 19% of the 290-490 W band, against a median of 30 yrs. - **Best for:** Residential and shaded-installations. - **Not ideal for:** Hot climates, tight roof space and owners who want a long output guarantee. ## Specification ### Electrical - **Rated power (Pmax):** 390 W - **Efficiency:** 19.90 % - **Voltage at Pmax (Vmp):** 30.76 V - **Current at Pmax (Imp):** 12.69 A - **Open-circuit voltage (Voc):** 36.62 V - **Short-circuit current (Isc):** 13.59 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.360 %/degC - **Temperature coefficient of Voc:** -0.304 %/degC - **Temperature coefficient of Isc:** 0.050 %/degC - **NOCT:** 42 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell count:** 108 ### Physical - **Length:** 1724 mm - **Width:** 1134 mm - **Thickness:** 30 mm - **Weight:** 22.1 kg - **Area:** 1.96 m2 - **Power density:** 199.5 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 25 years - **Output guaranteed at end of warranty:** 84.8 % - **First-year degradation:** 2.00 % - **Annual degradation:** 0.55 % - **Output after 30 years:** 320 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 12416 of 14129 | | Power density | 12376 of 14129 | | Temperature coefficient | 12425 of 14129 | | Weight | 10887 of 14129 | | Warranty | 9912 of 14129 | ## About this series Suntech Ultra V mini modules are designed to offer **maximum power density** for every square meter of available roof area. Through the use of modern cells based on M10 silicon wafers and Multi-Busbar technology, these panels effectively minimize resistive losses and increase sunlight absorption. This solution ideally addresses the needs of homeowners with limited installation space, where every centimeter of the roof is critical to the final profitability of the investment. The **exceptionally low weight of the modules** facilitates logistics and installation without placing an excessive load on the roof structure, which is particularly important when modernizing older buildings. The innovative **Half-Cut** cell structure guarantees stable system performance even during periodic shading, clearly setting this series apart from standard solutions currently available on the market. Suntech Ultra V mini also offers **increased resistance to PID degradation** and excellent temperature coefficients, ensuring high electricity production even on hot days. By choosing these panels, Polish investors receive a product that combines elegant design with premium-class technology, fully optimized for a rapid return on investment. ## Notable figures - At 19.9% efficiency, this panel is 1.9pp below the \*\*database\*\* median of 21.8% - Power density of 199.5 W/m² is 18.6 W/m² below \*\*database\*\* median (218.1 W/m²) - needs more roof space - At -0.36%/°C, loses 0.06pp more power per degree than \*\*database\*\* median (-0.30%/°C) - Weight of 22.1 kg (4.4 kg below \*\*database\*\* median of 26.5 kg) allows easier transport and roof mounting - In the top 88% for efficiency among all N-type panels ## Questions ### Is the Suntech Ultra V mini series still available for purchase? The Ultra V mini series has been discontinued by the manufacturer and replaced with newer product lines. This means availability is now limited to remaining distributor stock. It's worth checking current inventory with your supplier before planning a larger installation, since additional panels may not be available later to expand an existing system. ### What is the maximum power of the Suntech Ultra V mini module and how many panels are needed for a typical system? The module reaches a maximum power of 415 Wp thanks to TOPCon cells and half-cut technology. For a typical 5 kWp installation, roughly 12 panels are needed. Thanks to its high power density per square meter, this module fits more kilowatts on limited roof space than older PERC-based designs. ### What warranty comes with the Suntech Ultra V mini panels? The manufacturer provides a 12-year product warranty along with a 25-year power performance warranty. As a Tier 1 manufacturer based in China, Suntech offers service support in line with international industry standards, though the series' discontinuation is worth considering when planning future replacement of individual panels. ### What is TOPCon technology in the Ultra V mini panels, and is it better than PERC? TOPCon is an n-type cell technology that reduces recombination losses and delivers higher conversion efficiency than older PERC cells. In practice, this means higher energy output from the same panel area and better temperature performance, resulting in higher energy yields on hot days compared to conventional p-type modules. ### Are the Suntech Ultra V mini panels suitable for small pitched roofs? Yes, the Ultra V mini series was specifically designed for limited roof space. Compact dimensions combined with a high 415 Wp output help maximize energy production even on small roof sections. The module's low weight makes transport and installation on typical pitched roof structures easier, without overloading the roof truss. ### Is the Suntech Ultra V mini a bifacial panel? No, this specific version of the Ultra V mini series is a monofacial module, meaning it does not capture reflected light on its rear side. Suntech offers a separate Ultra V Pro mini version with bifacial technology, but this series focuses on maximizing front-side power output while keeping a lower weight and simpler construction. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/EN_Ultra_V_mini_STP410S_C54_Umh-e1cfc02f28fd.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Luxor Solar LX-440M/182-108+GG](https://comparepv.com/panel/luxor-solar-lx-440m-182-108-gg) | 440 W | +50 W, cooler, +3.2 pp | | [Gamko New Energy GKA210M340W](https://comparepv.com/panel/gamko-new-energy-gka210m340w) | 340 W | -50 W, lighter, +3.1 pp | | [Gamko New Energy GKA210M360W](https://comparepv.com/panel/gamko-new-energy-gka210m360w) | 360 W | Lighter, +3.1 pp, +5 yr warranty | | [Gamko New Energy GKA210M380W (1/4\*4\*38)](https://comparepv.com/panel/gamko-new-energy-gka210m380w-1-4-4-38) | 380 W | Lighter, +3.1 pp, +5 yr warranty | | [Gamko New Energy GKA210M400W (1/2\*4\*20)](https://comparepv.com/panel/gamko-new-energy-gka210m400w-1-2-4-20) | 400 W | Lighter, +3.1 pp, +5 yr warranty | | [Gamko New Energy GKA210M400W (1/4\*4\*40)](https://comparepv.com/panel/gamko-new-energy-gka210m400w-1-4-4-40) | 400 W | Lighter, +3.1 pp, +5 yr warranty | | [Gamko New Energy GKA210M380W (1/2\*4\*19)](https://comparepv.com/panel/gamko-new-energy-gka210m380w-1-2-4-19) | 380 W | Lighter, +3.1 pp, +5 yr warranty | | [Jetion JT440SYK(B)](https://comparepv.com/panel/jetion-jt440syk-b) | 440 W | +50 W, cooler, +3.0 pp | | [Suntech STP395S-C54/Umhm](https://comparepv.com/panel/wuxi-suntech-power-co-ltd-suntech-stp395s-c54-umhm) | 395 W | Cooler, lighter, +0.3 pp | | [Suntech STP395S-C54/Umh](https://comparepv.com/panel/suntech-stp395s-c54-umh) | 395 W | +0.3 pp | | [Suntech STP400S-C54/Umhm](https://comparepv.com/panel/wuxi-suntech-power-co-ltd-suntech-stp400s-c54-umhm) | 400 W | Cooler, lighter, +0.6 pp | | [Suntech STP400S-C54/Umh](https://comparepv.com/panel/suntech-stp400s-c54-umh) | 400 W | +10 W, +0.6 pp | | [Suntech STP405S-C54/Umhm](https://comparepv.com/panel/wuxi-suntech-power-co-ltd-suntech-stp405s-c54-umhm) | 405 W | +15 W, cooler, +0.8 pp | | [Suntech STP405S-C54/Umh](https://comparepv.com/panel/suntech-stp405s-c54-umh) | 405 W | +15 W, +0.8 pp | | [Longi Solar LR7-54HJD-510M](https://comparepv.com/panel/longi-lr7-54hjd-510m) | 510 W | +120 W, cooler, +5.1 pp | | [AIKO AIKO-A495-MCE54Mw](https://comparepv.com/panel/aiko-aiko-a495-mce54mw) | 495 W | +105 W, cooler, +4.9 pp | --- Source: https://comparepv.com/panel/suntech-stp390s-c54-umh Not in this file, on the page: a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.