--- title: "Suntech STP585S-C78/Pmhg Solar Panel: Specs & Datasheet | ComparePV" description: "Suntech STP585S-C78/Pmhg solar panel. Specs: 20.90% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/suntech-stp585s-c78-pmhg" image: "https://comparepv.com/og/panel/suntech-stp585s-c78-pmhg.png" updated: 2026-09-11 --- # Suntech STP585S-C78/Pmhg Middle of its segment, weak in heat 6,600 panels in the 485-685 W band, all technologies ## Identity - **Manufacturer:** Suntech - **Model:** STP585S-C78/Pmhg - **Series:** Ultra V Plus - **Rated power:** 585 W - **Cell technology:** Monocrystalline - **Bifacial:** yes ## How it compares Compared against 485-685 W band, all technologies (6600 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 585 W | 585 W | Typical | | | Module efficiency | 20.90% | 22.26% | Weak - bottom 12% | 10,148 | | Power density | 209.4 | 222.6 | Weak - bottom 14% | 10,041 | | Temperature coefficient | -0.360 | -0.300 | Weak - bottom 3% | 12,425 | | Weight (kg) | 31.1 kg | 31.0 kg | Typical | | | Performance warranty | 25 yrs | 30 yrs | Weak - bottom 11% | 9,912 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 20.90% | 22.26% | Weak - bottom 12% | 10,148 | | Power density | 209.4 | 222.6 | Weak - bottom 14% | 10,041 | | Temperature coefficient | -0.360 | -0.300 | Weak - bottom 3% | 12,425 | | Weight per kWp | 53.2 | 52.8 | Typical | 7,017 | | Performance warranty | 25 yrs | 30 yrs | Weak - bottom 11% | 9,912 | ### Watch out for - **-0.360 %/°C temperature coefficient** - Bottom 3% of the 485-685 W band, against a median of -0.300. Ranked 12,425th in the whole database. - **25 year performance warranty** - Bottom 11% of the 485-685 W band, against a median of 30 yrs. - **20.90% module efficiency** - Bottom 12% of the 485-685 W band, against a median of 22.26%. - **Best for:** Commercial, utility-scale and shaded-installations. - **Not ideal for:** Hot climates, owners who want a long output guarantee and tight roof space. ## Specification ### Electrical - **Rated power (Pmax):** 585 W - **Efficiency:** 20.90 % - **Voltage at Pmax (Vmp):** 45.18 V - **Current at Pmax (Imp):** 12.95 A - **Open-circuit voltage (Voc):** 53.61 V - **Short-circuit current (Isc):** 13.85 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:** 156 - **Bifacial:** yes - **Bifacial gain:** 25.00 ### Physical - **Length:** 2464 mm - **Width:** 1134 mm - **Thickness:** 35 mm - **Weight:** 31.1 kg - **Area:** 2.79 m2 - **Power density:** 209.4 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:** 480 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 10148 of 14129 | | Power density | 10041 of 14129 | | Temperature coefficient | 12425 of 14129 | | Weight | 7017 of 14129 | | Warranty | 9912 of 14129 | ## About this series Ultra V Plus is a series of **bifacial dual-sided modules** designed for investors who want to maximize energy yield from every square meter of roof or ground-mounted installation space. The panel uses **monocrystalline half-cut cells** arranged in a 6x26 layout, which reduces power losses from partial shading and improves reliability under demanding irradiance conditions. Thanks to multi-busbar technology and Suntech's proprietary current-sorting process, the module effectively eliminates electrical mismatch between cells, translating into a real increase in energy output from the system. The rear-side design allows for additional energy capture from light reflected off the ground, making the series particularly attractive for installations on bright surfaces, flat roofs, or ground-mount systems. The panels stand out with a **low power temperature coefficient**, losing less performance on hot days compared to competing solutions, along with strong output in low-light conditions such as mornings or overcast weather. The module has passed extended wind and snow load testing, confirming its durability in demanding climate conditions. The series is backed by a **30-year linear warranty** and low annual power degradation, making it a solid choice for both residential installations and large-scale commercial solar farm projects. ## Notable figures - At 20.9% efficiency, this panel is 0.9pp below the \*\*database\*\* median of 21.8% - Power density of 209.4 W/m² is 8.7 W/m² below \*\*database\*\* median (218.1 W/m²) - needs more roof space - -0.36%/°C temperature coefficient - 0.06pp worse than \*\*database\*\* median (-0.30%/°C), expect higher hot weather losses - At 31.1 kg, this panel is 4.6 kg heavier than the \*\*database\*\* median (26.5 kg) - more demanding for installation crews - Bifacial design (70% factor) captures reflected light - adds 4-10% yield on ground-mount or white roof ## Questions ### What is the maximum power output of the Suntech Ultra V Plus panel? Modules in the Ultra V Plus series reach a maximum power of up to 605 Wp. This high output comes from monocrystalline half-cut TOPCon cells, which deliver higher conversion efficiency than older PERC-based designs while keeping module dimensions comparable to standard panels. ### What warranty does Suntech offer on the Ultra V Plus series? The manufacturer provides a 15-year product warranty and a 30-year linear power warranty. This means that after 30 years of operation the module is guaranteed to still deliver a minimum specified power output, which is standard for modern TOPCon-based panels. ### Is the Suntech Ultra V Plus a bifacial (dual-sided) panel? No, this version of the Ultra V Plus is a monofacial module. It uses TOPCon technology with half-cut cells, but energy is generated only from the front side, unlike the bifacial variants in Suntech's Ultra V Pro lineup, where the rear side also contributes to power output. ### What is TOPCon technology and how does it differ from PERC? TOPCon (Tunnel Oxide Passivated Contact) is an n-type cell technology with an additional passivation layer that reduces carrier recombination and increases conversion efficiency compared to older p-type PERC cells. In practice this results in higher module power, a lower temperature coefficient, and slower annual power degradation over time. ### Is the Suntech Ultra V Plus suitable for large commercial and utility-scale solar farms? Yes, the high unit power of up to 605 Wp combined with a large cell format makes the series well suited to commercial rooftop installations as well as ground-mount systems and utility-scale solar farms, where maximizing energy yield per unit of land area matters most. ### Is Suntech a Tier 1 manufacturer, and is it worth buying panels from a Chinese producer? Suntech is classified as a Tier 1 manufacturer, indicating financial stability, in-house production lines, and a long-standing presence in the global market. The company is headquartered in China, but its modules are certified to European (IEC) standards and widely deployed across Poland and other EU markets, supporting warranty service availability. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/EN_Ultra_V_Plus_STP590S_C78_Pmhg-e594cf7949ed.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Longi Solar LR7-60HVH-560M](https://comparepv.com/panel/longi-lr7-60hvh-560m) | 560 W | Cooler, lighter, +3.9 pp | | [Longi Solar LR7-60HVH-555M](https://comparepv.com/panel/longi-lr7-60hvh-555m) | 555 W | Cooler, lighter, +3.7 pp | | [AIKO AIKO-A635-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a635-mae72mw) | 635 W | +50 W, cooler, +3.7 pp | | [AIKO AIKO-A630-MAH72Dw](https://comparepv.com/panel/aiko-aiko-a630-mah72dw) | 630 W | Cooler, +3.5 pp, +5 yr warranty | | [Longi Solar LR7-60HVHL-550M](https://comparepv.com/panel/longi-lr7-60hvhl-550m) | 550 W | Cooler, lighter, +3.5 pp | | [Suntech STP570S-C78/Pmh+](https://comparepv.com/panel/suntech-stp570s-c78-pmh) | 570 W | Heavier, -0.5 pp, +5 yr warranty | | [Suntech STP570S-C78/Pmhg](https://comparepv.com/panel/suntech-stp570s-c78-pmhg) | 570 W | -15 W, -0.5 pp | | [Suntech STP575S-C78/Pmh+](https://comparepv.com/panel/suntech-stp575s-c78-pmh) | 575 W | Cooler, heavier, +5 yr warranty | | [Suntech STP575S-C78/Pmhg](https://comparepv.com/panel/suntech-stp575s-c78-pmhg) | 575 W | -10 W, -0.3 pp | | [Suntech STP580S-C78/Pmh+](https://comparepv.com/panel/suntech-stp580s-c78-pmh) | 580 W | Cooler, heavier, +5 yr warranty | | [Suntech STP580S-C78/Pmhg](https://comparepv.com/panel/suntech-stp580s-c78-pmhg) | 580 W | Very close match | | [Suntech STP585S-C78/Pmh+](https://comparepv.com/panel/wuxi-suntech-power-co-ltd-stp585s-c78-pmh) | 585 W | Cooler, heavier, +5 yr warranty | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | +95 W, cooler, +4.3 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | +90 W, cooler, +4.1 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | +115 W, cooler, +4.1 pp | | [WINAICO WST-675BKX72-A2](https://comparepv.com/panel/winaico-wst-675bkx72-a2) | 675 W | +90 W, cooler, +4.1 pp | --- Source: https://comparepv.com/panel/suntech-stp585s-c78-pmhg Not in this file, on the page: the I-V and temperature curves lifted from the manufacturer's datasheet, a thirty-year output simulator, a bifacial gain calculator and alternatives filtered by how closely they match these dimensions.