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About the Tool
SolarPro Designer
India's free, professional-grade solar PV design tool — trusted by solar engineers, installers, and EPC contractors.
What is SolarPro Designer?
SolarPro Designer is a free, professional-grade web application built by Renewix Innovations that allows solar engineers, installers, and EPC contractors to instantly generate compliant Solar PV Single Line Diagrams (SLDs). Solar installers using SolarPro Designer generate a compliant SLD in under 3 minutes, compared to 2–4 hours of manual CAD work — saving over 95% of design time.
< 3 min
SLD generation time
100%
Free, no login needed
13+
Indian cities modeled
Key Features
Auto SLD Generation: Visually renders interactive, compliance-ready Single Line Diagrams instantly for LT and HT grid connections.
Auto String Sizing: Calculates optimal panel strings with Voc, Vmp, and MPPT validation for grid-tied and hybrid inverters.
Yield Analysis: Physics-based solar irradiance modeling with hourly generation profiles across all 12 months.
BESS & ROI Sizing: Battery Energy Storage System sizing with ROI projections, payback period, and lifetime savings.
BOM Creation: Dynamically generates a complete Bill of Materials including modules, inverters, cables, protection devices, and earthing.
PDF Reports: Export clean, professional PDF reports for clients and Indian DISCOM net metering approval submissions.
Designed by MNRE-certified solar engineers at Renewix Innovations, Vadodara, Gujarat.
How to Calculate Solar String Sizing
To calculate solar string sizing accurately, you must ensure the total Open Circuit Voltage (Voc) of the panels in series does not exceed the inverter's maximum input voltage, while the Maximum Power Voltage (Vmp) remains within the inverter's optimal MPPT operating range. Here's how SolarPro Designer automates this:
1
Enter Solar Module Specifications
Input your panel's Wp, Voc, Vmp, Isc, and Imp from the module datasheet.
2
Set Inverter MPPT Parameters
Enter max DC voltage, MPPT voltage range, number of MPPTs, and max DC current per tracker.
3
Configure String Layout
Specify strings and panels per string. The tool auto-validates total Voc and Vmp against inverter limits.
4
Review Validation Results
Green indicators show compliant configurations; red flags indicate voltage or current violations.
5
Generate & Export SLD
Once validated, generate the complete SLD and export as PDF for DISCOM submission.
Frequently Asked Questions
What is the maximum string voltage I can use for a 5kW inverter?
For a typical 5kW residential inverter, the maximum DC input voltage is usually 500V–600V. You must ensure the total Open Circuit Voltage (Voc) of panels connected in series does not exceed this limit, especially accounting for cold-temperature Voc rise. SolarPro Designer calculates this automatically based on your selected inverter specifications.
How does SolarPro Designer calculate MPPT range?
SolarPro Designer calculates the optimal MPPT operating range by checking that the total Maximum Power Voltage (Vmp) of the string falls within the inverter's MPPT voltage window. It validates that Vmp x number of panels per string is between the inverter's MPPT minimum and maximum voltage, ensuring peak power extraction.
Is SolarPro Designer free for commercial projects?
Yes, SolarPro Designer is completely free for both residential and commercial solar PV projects. There is no login required, no usage limits, and no premium tier. It supports systems from 5kW residential to 500kW+ commercial/industrial installations.
What Indian DISCOM approval formats does the SLD support?
SolarPro Designer generates Single Line Diagrams that comply with standard Indian DISCOM requirements for net metering applications. The SLD includes all required components — solar modules, inverters, DCDB, ACDB, protection devices (SPD, MCB, MCCB, ELCB), metering, earthing, and lightning arrestor — in the format expected by state electricity boards across Gujarat (GUVNL/DGVCL), Maharashtra (MSEDCL), Rajasthan (JVVNL), and other states.
How accurate is the solar yield analysis?
SolarPro Designer uses a physics-based solar irradiance model that calculates sun position, angle of incidence, and plane-of-array irradiance for any location. It models hourly generation profiles across all 12 months using the Perez diffuse irradiance model and accounts for temperature derating, soiling losses, and inverter efficiency. Results are within 5–8% of actual field measurements for Indian locations.
Can I design HT (High Tension) grid-connected systems?
Yes, SolarPro Designer supports both LT (415V) and HT (11kV) grid connections. For HT systems, the SLD automatically includes step-up transformers, HT vacuum circuit breakers (VCB), HT bi-directional metering, and appropriate protection schemes. This is ideal for large commercial and industrial installations above 100kW.
What inverter brands are supported?
SolarPro Designer allows you to enter specifications for any grid-tied string inverter. It comes with pre-configured templates for popular brands including KSolar, Sungrow, Delta Electronics, and others. You can customize all inverter parameters including rated AC power, max DC voltage, MPPT range, number of MPPTs, and maximum DC Isc.
How does the auto string sizing work?
Auto string sizing validates three critical parameters: (1) Total string Voc must not exceed inverter maximum DC input voltage, (2) Total string Vmp must fall within the inverter MPPT voltage window, and (3) String short-circuit current (Isc) must not exceed inverter maximum DC input current per MPPT. The tool automatically flags any violations and suggests optimal configurations.
Does SolarPro Designer support BESS (Battery Energy Storage)?
Yes, SolarPro Designer includes a BESS sizing module that calculates optimal battery capacity based on your solar generation profile, load requirements, and desired backup duration. It provides ROI projections including payback period, lifetime savings, and levelized cost of storage (LCOS) to help you make informed investment decisions.
Can I export SLDs as PDF for DISCOM net metering submission?
Yes, SolarPro Designer exports professional-grade PDF reports that include the complete Single Line Diagram, project specifications, string sizing validation, Bill of Materials (BOM), and yield analysis. These PDFs are formatted for direct submission to Indian DISCOMs as part of the net metering application process.
How SolarPro Designer Compares
Feature
SolarPro Designer
Helioscope
Aurora Solar
Monthly Price
Free ($0 INR)
~$180 / month
~$200 / month
Auto SLD Generation
Yes (Instant)
No (Manual CAD needed)
No (Layout only)
Indian DISCOM Formats
Yes (MNRE Compliant)
No
No
BESS Sizing & ROI
Yes
No
Yes
No Signup Required
Yes (No Login)
No
No
Trusted by Solar Professionals
Used by over 500+ solar installers, EPC contractors, and rooftop solar engineers across Gujarat, Maharashtra, Rajasthan, and other states in India to streamline net metering approvals and client proposals.