--- title: "Suntech STP345S-A66/Ssh Solar Panel: Specs & Datasheet | ComparePV" description: "Suntech STP345S-A66/Ssh solar panel. Specs: 19.70% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/suntech-stp345s-a66-ssh" image: "https://comparepv.com/og/panel/suntech-stp345s-a66-ssh.png" updated: 2026-09-11 --- # Suntech STP345S-A66/Ssh Light for its output, weak in heat 291 panels in the segment PERC 300-350 W ## Identity - **Manufacturer:** Suntech - **Model:** STP345S-A66/Ssh - **Series:** HiSpec 396 Half-Cell Monofacial Module - **Rated power:** 345 W - **Cell technology:** PERC ## How it compares Compared against segment PERC 300-350 W (291 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 345 W | 325 W | Strong - top 4% | | | Module efficiency | 19.70% | 19.00% | Strong - top 21% | 12,596 | | Power density | 196.7 | 190.0 | Strong - top 20% | 12,613 | | Temperature coefficient | -0.380 | -0.360 | Weak - bottom 23% | 13,477 | | Weight (kg) | 19.0 kg | 19.0 kg | Strong - top 7% | | | Performance warranty | 25 yrs | 25 yrs | Typical | 9,912 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 19.70% | 19.00% | Strong - top 21% | 12,596 | | Power density | 196.7 | 190.0 | Strong - top 20% | 12,613 | | Temperature coefficient | -0.380 | -0.360 | Weak - bottom 23% | 13,477 | | Weight per kWp | 55.1 | 60.3 | Strong - top 7% | 9,561 | | Performance warranty | 25 yrs | 25 yrs | Typical | 9,912 | ### Strengths - **55.1 kg per kWp** - Top 7% of the PERC 300-350 W segment, against a median of 60.3. Ranked 9,561st in the whole database. - **196.7 watts per square metre** - Top 20% of the PERC 300-350 W segment, against a median of 190.0. - **19.70% module efficiency** - Top 21% of the PERC 300-350 W segment, against a median of 19.00%. ### Watch out for - **-0.380 %/°C temperature coefficient** - Bottom 23% of the PERC 300-350 W segment, against a median of -0.360. - **Best for:** Residential, commercial and shaded-installations. - **Not ideal for:** Hot climates. ## Specification ### Electrical - **Rated power (Pmax):** 345 W - **Efficiency:** 19.70 % - **Voltage at Pmax (Vmp):** 38.59 V - **Current at Pmax (Imp):** 8.94 A - **Open-circuit voltage (Voc):** 46.49 V - **Short-circuit current (Isc):** 9.53 A - **Max system voltage:** 1000 V ### Temperature - **Temperature coefficient of Pmax:** -0.380 %/degC - **Temperature coefficient of Voc:** -0.310 %/degC - **Temperature coefficient of Isc:** 0.048 %/degC - **NOCT:** 43 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** PERC - **Cell count:** 396 ### Physical - **Length:** 1740 mm - **Width:** 1008 mm - **Thickness:** 35 mm - **Weight:** 19.0 kg - **Area:** 1.75 m2 - **Power density:** 196.7 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 25 years - **Output guaranteed at end of warranty:** 80.2 % - **First-year degradation:** 2.50 % - **Annual degradation:** 0.50 % - **Output after 30 years:** 286 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 12596 of 14129 | | Power density | 12613 of 14129 | | Temperature coefficient | 13477 of 14129 | | Weight | 9561 of 14129 | | Warranty | 9912 of 14129 | ## About this series The HiSpec 396 Half-Cell Monofacial series consists of monocrystalline PERC modules built from 396 **half-cut cells**, which reduces resistive losses and allows the module to better withstand partial shading without a drastic drop in string output. HD technology eliminates gaps between cells, increasing the active surface area of the panel, while a unique circuit design lowers electrode resistance and improves the fill factor. This makes it a solid choice for installers and investors looking for panels that combine **high conversion efficiency** with resilience in demanding operating conditions - the modules have passed extended wind and snow load testing, making them suitable for roofs exposed to extreme weather. The panels also stand out for their **excellent weak-light performance**, delivering real energy gains during mornings, evenings, and cloudy days, while a lower operating temperature limits power losses on hot days. The integrated **IP68-rated junction box** provides reliable moisture protection regardless of mounting orientation. Through current sorting during manufacturing, Suntech minimizes mismatch losses across the module string, translating into higher real-world energy yield compared to competing solutions in this class. ## Notable figures - At 19.7% efficiency, this panel is on par with typical \*\*PERC 0-400W\*\* modules - At 196.7 W/m² power density, roof space requirements are typical for \*\*PERC 0-400W\*\* panels - -0.38%/°C temperature coefficient - 0.02pp worse than \*\*PERC 0-400W\*\* median (-0.36%/°C), expect higher hot weather losses - At 19.0 kg, this panel is 1.5 kg lighter than \*\*PERC 0-400W\*\* median (20.5 kg) - easier handling during installation - In the top 89% for efficiency among all PERC panels ## Questions ### What warranty comes with the Suntech HiSpec 396 Half-Cell Monofacial panels? The manufacturer provides a 12-year product warranty and a 25-year linear power output warranty. The module reaches a maximum power of 365 Wp, and current-matched cell sorting minimizes mismatch losses within the module string, helping the array maintain its rated output over the system's lifetime. ### What are half-cut cells in the HiSpec 396 and what benefit do they bring? The module uses 396 half-cut monocrystalline PERC cells, meaning each cell is cut in half. This reduces resistive current losses, lowers electrode resistance, and helps the panel tolerate partial shading - from a chimney or antenna, for example - without a drastic drop in string output, resulting in higher real-world energy yield. ### Is the Suntech HiSpec 396 Half-Cell Monofacial series still available for purchase? No, production of this series has ended and the module is discontinued from the manufacturer's current lineup. Remaining units may still be available through distributors as clearance stock, but for new installations it's worth asking your supplier about the current equivalent model with an active service warranty going forward. ### Can the HiSpec 396 panels handle heavy snow loads and strong wind? Yes, HiSpec 396 modules have passed extended wind and snow load testing, making them suitable for roofs exposed to demanding weather conditions, including heavy snowfall and gusty winds. This is a key consideration when choosing panels for buildings in regions with variable, harsh climates. ### How does the HiSpec 396 perform in low-light and hot weather conditions? The panel offers strong low-irradiance performance, delivering real energy gains in the morning, evening, and on overcast days. It also runs at a lower operating temperature, which limits power losses during hot summer days, keeping the array's output more stable compared to modules with weaker temperature coefficients. ### Is the junction box on the HiSpec 396 protected against moisture regardless of mounting angle? Yes, the module features a sealed IP68-rated junction box that provides lasting protection against moisture and water ingress regardless of the panel's mounting orientation. This matters especially for flat-roof installations or sites prone to rainwater pooling near the connection point. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/EN_HISpec_STP365S_A66_Ssh-8a1b1cc681a3.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [JA Solar NS-300MH-72](https://comparepv.com/panel/ja-solar-ns-300mh-72) | 300 W | Cooler, lighter, +3.6 pp | | [PolyCrown Solar Tech NS-300MH-72](https://comparepv.com/panel/polycrown-solar-tech-ns-300mh-72) | 300 W | Cooler, lighter, +3.6 pp | | [JA Solar NS-330MH-80](https://comparepv.com/panel/ja-solar-ns-330mh-80) | 330 W | Cooler, lighter, +3.4 pp | | [PolyCrown Solar Tech NS-330MH-80](https://comparepv.com/panel/polycrown-solar-tech-ns-330mh-80) | 330 W | Cooler, lighter, +3.4 pp | | [Gamko New Energy GKA182M300W](https://comparepv.com/panel/gamko-new-energy-gka182m300w) | 300 W | -45 W, +3.3 pp, +5 yr warranty | | [Gamko New Energy GKA210M320W](https://comparepv.com/panel/gamko-new-energy-gka210m320w) | 320 W | Lighter, +3.3 pp, +5 yr warranty | | [Gamko New Energy GKA210M340W](https://comparepv.com/panel/gamko-new-energy-gka210m340w) | 340 W | Lighter, +3.3 pp, +5 yr warranty | | [Gamko New Energy GKA210M360W](https://comparepv.com/panel/gamko-new-energy-gka210m360w) | 360 W | Lighter, +3.3 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 | +35 W, +3.3 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 | +35 W, +3.3 pp, +5 yr warranty | | [Suntech STP350S-A66/Ssh](https://comparepv.com/panel/suntech-stp350s-a66-ssh) | 350 W | +0.3 pp | | [Suntech STP355S-A66/Ssh](https://comparepv.com/panel/suntech-stp355s-a66-ssh) | 355 W | +10 W, +0.5 pp | | [Suntech STP360S-A66/Ssh](https://comparepv.com/panel/suntech-stp360s-a66-ssh) | 360 W | +15 W, +0.8 pp | | [Suntech STP365S-A66/Ssh](https://comparepv.com/panel/suntech-stp365s-a66-ssh) | 365 W | +20 W, +1.1 pp | | [Jetion JT440SYK(B)](https://comparepv.com/panel/jetion-jt440syk-b) | 440 W | +95 W, cooler, +3.2 pp | | [Jetion JT435SYk(B)](https://comparepv.com/panel/jetion-jt435syk-b) | 435 W | +90 W, cooler, +3.0 pp | --- Source: https://comparepv.com/panel/suntech-stp345s-a66-ssh Not in this file, on the page: a thirty-year output simulator and alternatives filtered by how closely they match these dimensions.