Description
The Largest Practical String Inverter Before Projects Split or Centralise
Solar engineering has a specific architectural decision point at around 100–125kW per inverter unit. Below this threshold, single-string-inverter installations dominate because they’re simpler, cheaper, and more fault-tolerant. Above this threshold, projects typically either split into multiple smaller inverters (gaining redundancy at the cost of more equipment to maintain) or shift to central inverter topologies (gaining cost-per-watt savings at the cost of single-point-of-failure risk).
The Solis-110K-5G — sold in commercial markets as the 125kVA-class flagship of the Solis 5G string inverter range — sits exactly at this architectural inflection point. It’s the largest single-unit string inverter most Kenyan industrial and commercial projects will deploy. For projects sized between 110kW and 220kW, two of these in parallel often provides the optimal balance of capacity, redundancy, and cost.
Same Platform as the 100kW, More Headroom
The Solis-110K-5G shares its hardware platform with the Solis-100K-5G — same 10-MPPT architecture, same chassis design, same protection ratings, same smart features. The differences are in the power electronics rating:
- 10% more rated continuous output: 110kW vs 100kW
- 10% more peak output capability: 121kW max vs 110kW
- 10% more apparent power: 121 kVA vs 110 kVA
- 10% more AC output current: 167.1A rated per phase vs 152.0A
- 10% more PV input capacity at the same DC/AC ratio: 165kW max array vs 150kW
The shared platform means installers familiar with the 100kW model can deploy the 125kVA variant with no learning curve, and any additional units added later (whether 100K or 110K class) integrate seamlessly. The chassis dimensions, mounting hardware, and SolisCloud configuration are identical.
Why Pick the 125kVA Class Specifically
The decision between the 100kW and 110kW (125kVA class) platforms usually comes down to specific project economics:
- You have specific PV array capacity above 150kW: The 100kW model caps at 150kW PV input (1.5× ratio). If your specific roof or ground area accommodates 160–165kW of panels, the 110K version captures the additional 10kW of solar generation rather than wasting it.
- You’re sizing for future expansion within the same inverter: Industrial sites planning to add panels later often size the inverter for the eventual full deployment from day one. The 125kVA class accommodates roughly 10% more capacity headroom than the 100kW unit.
- Your AC infrastructure is sized for higher current: If your three-phase electrical infrastructure can handle 200A+ per phase comfortably, the 110K’s higher output makes use of that capacity. Sites with constrained AC infrastructure should choose the 100kW instead.
- Per-watt cost economics favour 110K at this size: The price increment from 100K to 110K is typically much smaller than the 10% capacity increase, giving a slightly better price-per-watt ratio for sites where the extra capacity is genuinely usable.
What Industrial Operations Need 110kW+ Capacity
- Large manufacturing facilities: Substantial production lines, multiple compressors, paint shops, ventilation systems, and full plant lighting. Daily consumption exceeding 700 kWh on three-phase commercial supply.
- Cold storage warehouses and fish/meat processing: Heavy continuous refrigeration loads requiring substantial daytime offset. Cold chain operations particularly benefit from solar offsetting their largest operational cost.
- Tea factories and large agricultural processors: Withering, processing, drying, and packaging operations with substantial daytime electricity demand matching solar generation profiles.
- Large hotels and resort properties (150+ rooms): Full hospitality infrastructure with extensive HVAC, kitchens, laundry, conference facilities, and back-of-house operations.
- Large hospitals and university teaching hospitals: Multi-building healthcare campuses with continuous baseline loads from medical equipment, sterilisation, HVAC, and ancillary services.
- Shopping malls and large retail complexes: Multi-tenant retail with extensive common-area infrastructure, multiple food-service tenants, central HVAC, and substantial lighting loads.
- Industrial parks and manufacturing clusters: Shared infrastructure, common facilities, lighting, security, and water systems for industrial parks hosting multiple tenant operations.
- Large educational institutions: Universities, polytechnics, and large secondary schools with extensive multi-building campuses.
The String Inverter vs Central Inverter Decision Point
For solar projects above 100–150kW, the design choice between multiple string inverters versus single central inverter matters significantly. Choosing multiple Solis-110K-5G units (string inverter approach) versus a single central inverter at the same total capacity has these trade-offs:
String inverter advantages (this product):
- Granular fault tolerance — one inverter failure affects only that inverter’s section, not the entire system
- Smart string monitoring across 10 MPPTs per inverter
- Faster installation — wall-mounted units, simpler DC management, no specialised central inverter pad/foundation
- Better optimisation for non-uniform array conditions (multi-orientation, partial shading)
- Simpler maintenance — replacing a single inverter is straightforward
- No requirement for specialised central-inverter cooling infrastructure
Central inverter advantages (the alternative):
- Lower cost-per-watt at scales above 500kW
- Single point of monitoring and management
- Higher single-unit efficiency in optimal conditions
- Simpler AC infrastructure (single high-current AC connection)
For projects in the 110–220kW range, multiple Solis-110K-5G units are typically the optimal choice. Above 500kW, central inverters often become more cost-effective despite their drawbacks.
Three Realistic 125kVA-Class Industrial Installations
Profile A — Large manufacturing facility: 285 × Canadian Solar 580W TOPHiKu6 panels (165.3kW DC) split across 10 MPPT trackers + Solis-110K-5G grid-tied inverter. Powers production machinery, multiple compressors, paint booths, ventilation, lighting, and office. Heavy daytime industrial loads achieve excellent direct solar self-consumption.
Profile B — Cold storage warehouse: 300 × Jinko Tiger Neo 550W panels (165kW DC) + Solis-110K-5G. Cold storage compressors and freezer banks provide nearly continuous daytime load matching solar generation almost perfectly. Night SVG corrects power factor across the heavy compressor loads, eliminating utility reactive power penalties.
Profile C — University teaching hospital: 247 × Canadian Solar 670W HiKu7 panels (165.49kW DC) + Solis-110K-5G. Powers diagnostic equipment, sterilisation, HVAC across multiple buildings, lighting, kitchen, laundry, and ancillary services. Critical loads (operating theatres, ICU) backed separately by hospital generators; solar handles bulk daytime baseline consumption.
Specifications
PV Input (DC Side)
| Parameter | Value |
|---|---|
| Recommended Max. PV Power | 165,000 W |
| Max. DC Input Voltage | 1,100 V |
| Rated DC Voltage | 600 V |
| Start-up Voltage | 195 V |
| MPPT Voltage Range | 180 – 1,000 V |
| Max. Input Current per MPPT | 26 A |
| Max. Short-Circuit Current per MPPT | 40 A |
| Number of MPPTs / Strings | 10 MPPTs / 20 strings |
| DC/AC Ratio | 1.5× |
| PV Connection | MC4 connectors (Y-connector supported) |
| Integrated DC Switch | Yes |
AC Output (Grid Side)
| Parameter | Value |
|---|---|
| Rated Output Power | 110,000 W |
| Max. Output Power | 121,000 W |
| Max. Apparent Output Power | 121 kVA (sold as 125kVA class) |
| Rated Grid Voltage | 3/N/PE, 220V/380V or 230V/400V |
| Rated Grid Frequency | 50 Hz / 60 Hz |
| Rated Output Current per Phase | 167.1 A / 158.8 A |
| Max. Output Current | 183.8 A |
| Power Factor | >0.99 (adjustable 0.8 leading – 0.8 lagging) |
| THDi | <3% |
| DC Injection Current | <0.5% In |
| Aluminium Wire Support | Yes |
Efficiency
| Parameter | Value |
|---|---|
| Max. Efficiency | 98.7% |
| European Efficiency | 98.5% |
| MPPT Efficiency | 99.9% |
Smart Industrial Features
| Feature | Status |
|---|---|
| Night SVG (Reactive Power Compensation) | Yes (24-hour power factor correction) |
| AFCI (Arc-Fault Detection) | Yes (industrial fire safety) |
| Smart String Monitoring | Yes (per-string real-time) |
| Smart I-V Curve Scanning | Yes (automated fault diagnosis) |
| Bifacial Module Support | Yes |
| PID Recovery (Optional) | Yes |
| Power Line Communication (PLC) | Optional |
| Export Power Control | Yes (with optional EPM/meter) |
| Remote Firmware Updates | OTA via SolisCloud |
Protection & Safety
| Feature | Status |
|---|---|
| Anti-islanding Protection | Yes (mandatory grid safety) |
| Output Over-current Protection | Yes |
| Short-circuit Protection | Yes |
| DC Reverse-polarity Protection | Yes |
| Insulation Resistance Detection | Yes |
| Residual Current Protection | Yes |
| Surge Protection | DC Type II / AC Type II |
| Integrated DC Switch | Yes |
| Over-temperature Protection | Yes |
| Ground Fault Protection | Yes |
Communication & Monitoring
| Parameter | Value |
|---|---|
| Standard Communication | RS485 |
| Optional Communication | Wi-Fi, Ethernet, Cellular, PLC |
| Display | LCD + indicator LEDs |
| Remote Monitoring Platform | SolisCloud (web + mobile) |
| Per-String Performance Tracking | Real-time via SolisCloud |
| Multi-Inverter Site Management | Aggregated dashboard for parallel installations |
Physical & Environmental
| Parameter | Value |
|---|---|
| Ingress Protection | IP66 |
| Cooling Method | Intelligent fan cooling |
| Operating Temperature | -25°C to +60°C |
| Topology | Transformerless |
| Mounting | Wall-mounted vertical |
What’s Required for a 125kVA-Class Industrial Installation
You’ll need solar panels (typically 247–300 modules of 550W–670W class), commercial DC string protection rated for 1100V+, three-phase AC switchgear sized for 250A+ per phase, professional earthing and surge protection, industrial-grade mounting hardware (rooftop, ground-mount, or carport), an export power manager and meter where utility connection requires it, and EPRA-licensed installation by a contractor experienced specifically with large industrial grid-tied systems.
For projects above 220kW total capacity, multiple Solis-110K-5G units in parallel are typically the optimal architecture. We can quote multi-inverter configurations directly. This is a grid-tied installation — there is no battery storage and no role for our Jinko, Renergy, or Vestwood battery products in this configuration. Industrial sites needing backup typically use separate standby generation or AC-coupled storage on critical-load circuits only.
At this scale, professional engineering review with site-specific load analysis and roof/ground-mount design is essential. Request an industrial quote or WhatsApp 0794 917 789 to arrange a site consultation with our commercial team.
Solis 125kVA-Class Grid-Tied: Industrial Buyer Questions
Why is this called the 125kVA inverter when the model is “110K”?
The model number reflects the rated continuous output (110kW). The 125kVA designation reflects the maximum apparent power (121 kVA, rounded to 125 kVA in commercial parlance). Inverter sizing in Kenyan commercial contexts typically uses kVA terminology to align with utility connection ratings, even though the actual continuous power output is specified in kW. The Solis-110K-5G is functionally the largest inverter in the Solis 5G three-phase grid-tied range below the utility-scale 150K and 200K models.
Is this just a slightly bigger 100kW model?
The 110K and 100K share identical hardware platforms — same chassis, same 10-MPPT architecture, same smart features, same protection. The differences are in power electronics rating (110kW vs 100kW continuous, 121 kVA vs 110 kVA apparent) and the resulting AC output current. The platform similarity means the choice between them is purely about whether your specific project needs the additional 10% capacity headroom.
When should I choose the 125kVA over the 100kW?
Choose the 125kVA class if: (1) your specific roof or ground area accommodates 160–165kW of panels (the 100kW caps at 150kW PV); (2) you’re sizing for future panel expansion within the same inverter; (3) your AC infrastructure handles 200A+ per phase comfortably; (4) the per-watt cost economics favour the larger unit at your specific procurement quote. Otherwise, the 100kW saves slightly on capital cost and works equally well.
For projects above 200kW, do I install one big inverter or multiple Solis 125kVA?
For total capacity 110–500kW, multiple Solis-110K-5G units in parallel are typically optimal: better fault tolerance (one inverter failure affects only that section), simpler maintenance (replace one wall-mounted unit vs servicing a central inverter), better array optimisation, and faster installation. Above 500kW, central inverters often become more cost-effective per watt despite the single-point-of-failure risk. The Solis-110K-5G platform supports unlimited parallel installations on a single site.
Does the Night SVG function actually save money for industrial sites?
Yes, for industrial sites with reactive power penalties or power factor charges in their utility tariff. Industries with heavy inductive loads (motors, compressors, fluorescent lighting, welders) often have natural power factors of 0.75–0.85, triggering monthly utility penalty charges. The Night SVG function provides automatic power factor correction 24/7 — solar power factor correction during the day, reactive-only correction at night. For affected sites, the savings on reactive power charges alone can offset a meaningful portion of the inverter’s lifetime cost.
How does smart string monitoring work at 20-string scale?
The inverter monitors voltage, current, and power on each of its 20 PV strings independently in real-time. SolisCloud displays per-string performance comparisons, instantly highlighting underperformers. Smart I-V curve scanning periodically tests each string and identifies fault types (degraded panels, partial shading, soiling, connector issues, ground faults) before manual inspection is needed. Performance alerts route to system owner and installer with specific string identification — eliminating wasted hours of climbing roofs and testing every string manually.
What’s the realistic payback for 125kVA-class industrial solar in Kenya?
Highly site-specific, but typical Kenyan industrial 110kW installations achieve payback in 2.5–3.5 years where daytime operation aligns with solar generation. Continuous-operation industrial sites (cold storage, manufacturing, processing) and those subject to reactive power penalties (where Night SVG provides additional savings) can achieve payback under 3 years. After payback, the system continues generating substantially free electricity for another 20+ years.
How much space does a 125kVA-class system need?
For 165kW of panels, plan for 800–1,000 square metres of clear, well-oriented mounting area. Industrial buildings typically have sufficient roof; ground-mount or carport-mount supplement where roof constraints exist. The 10-MPPT design supports splitting the array across multiple roof sections, ground-mount areas, and carport structures without performance compromise.
Can the Solis 125kVA inverter handle my high-voltage panel strings?
Yes. The 1,100V maximum DC input voltage allows long string configurations on commercial and industrial layouts. With 20 strings supported across 10 MPPTs (2 strings per MPPT), you have substantial flexibility in string sizing — typically 18–24 panels per string of modern 550W+ modules without exceeding voltage limits.
Warranty and where to buy in Kenya?
Solis provides a 5-year standard manufacturer warranty on the Solis-110K-5G, extendable to 10 years through Solis-certified channel programs. Bicity Solar Energy Suppliers stocks this inverter with delivery to all 47 counties. Industrial-scale projects benefit from direct engineering consultation. WhatsApp 0794 917 789 or request an industrial quote for current pricing and project consultation.
