Most rooftop sales in India are won or lost on the first visit. PitchSun is solar design software built for that visit: drop a pin on the customer's house, get the roof from satellite imagery, place panels around the water tank and the mumty, see which modules lose sun in December, and turn it all into a priced, subsidy-ready proposal without retyping a single number.
It is made for Indian installers, EPCs and channel partners who design small and mid-size rooftop systems every day, not for a CAD team with a week per project. Every step below is part of the same workspace as your quotes, CRM and PM Surya Ghar paperwork.
What PitchSun's solar design software does
One-click roof detection
Pick the building and PitchSun draws the roof outline from Google Solar API data, including parapet height, water tanks and staircase rooms. Attached row houses are separated by roof level, so you design only your customer's terrace.
Satellite roof tracing
Where you prefer to draw it yourself, trace the roof over satellite imagery. If high-resolution tiles are missing for a town, the map falls back to the best zoom available instead of showing a blank screen.
Obstructions that match Indian roofs
Add tanks, mumtys, trees and other obstructions with their heights. The layout keeps a shadow buffer around each one rather than packing panels right up against it.
Auto panel layout
Panels are placed with setbacks and walkways, and row spacing is worked out from winter-solstice sun angles. The layout is aware of RCC elevated, low-rise and tin-shed structures.
Per-module shading analysis
Year-round ray-traced shading for every module shows exactly which panels lose output and when, so you can move or drop them before the customer asks.
3D view with sun slider
Show the customer their roof in 3D and drag the sun through the day. It is the quickest way to explain why a panel moved away from the tank.
Generation from PVGIS
Yield is estimated with PVGIS 5.3 (ERA5, horizon-aware) for the exact location and orientation, with a state-average fallback so a quote never stalls.
Strings, cables and SLD
String sizing against inverter limits, voltage-drop cable sizing from real run lengths, and an auto-generated single-line diagram for your files and the DISCOM.
How a rooftop solar design comes together
- Find the roof. Drop a pin on the customer's house, then use Detect roof at pin or trace the outline on satellite imagery.
- Mark what is in the way. Detected tanks, staircase rooms, parapets and taller neighbours within 12 m come in as obstructions; add or adjust anything the satellite missed.
- Lay out the panels. Pick the module and structure type and let auto-layout fill the usable area. Move, add or remove modules by hand where you want.
- Run shading. Check per-module losses through the year and see them in 3D with the sun slider.
- Check the electricals. Confirm strings, DC/AC ratio, cable sizes and the SLD.
- Send the proposal. System size, generation and savings flow into a branded proposal with the PM Surya Ghar subsidy and GST already applied.
If you are starting from the customer's bill rather than the roof, size the system first. Our guide on how to calculate solar system size from an electricity bill explains the kW formula, roof area and panel count, and the design then confirms whether that size actually fits.
Solar shading analysis software that knows about mumtys
Indian terraces are crowded: a water tank on a steel stand, a staircase room, a neighbour's extra floor, a coconut or neem tree over the boundary wall. A shade estimate that ignores these is the fastest way to overpromise generation and end up with an unhappy customer and a service ticket.
PitchSun's shading engine samples six points on each module, every 30 minutes, across 12 representative days of the year, and ray-traces them against obstructions, parapets and other panel rows. When you use roof detection, it also picks up taller neighbours and trees within 12 m from the elevation data. Because the maths runs in a background worker, the design stays responsive even with a few hundred modules on screen.
From PV design to proposal, with no retyping
A design is only useful if it becomes a quote the customer understands. In PitchSun the designed capacity feeds straight into the quote: DCR modules and inverter from your own price list, GST at the 70:30 split, the correct PM Surya Ghar central financial assistance, a month-by-month net-metering bill simulation, and payback, IRR and EMI against savings. You can cross-check the subsidy figure with our free solar subsidy calculator.
The result is a branded web proposal you send as a WhatsApp link, with open tracking, online acceptance and an A4 PDF of the same page. Customers can read it in English, Hindi, Marathi, Gujarati, Tamil, Telugu, Kannada or Bengali. See PitchSun's solar proposal software for how that side works.
After installation, the same expected generation is what monitoring compares against, so underperformance alerts are measured against what you actually promised.
How it compares
| PitchSun | Spreadsheets + WhatsApp | Global design tools | |
|---|---|---|---|
| Roof from satellite imagery | Yes, traced or detected | No | Usually |
| Tanks, mumtys and elevated structures | Built into auto-layout | Guesswork | Often needs manual modelling |
| Per-module shading through the year | Yes | No | Usually |
| PM Surya Ghar subsidy and GST 70:30 in the quote | Yes | Manual formulas | Rarely |
| Proposal on WhatsApp in regional languages | Yes | Screenshots and PDFs | Rarely |
| Pricing | In rupees, from ₹0 | Free | Often in USD |
A solar system design app for the rooftop, not only the office
PitchSun works in the browser on a phone, tablet or laptop, so a salesperson can adjust the layout with a finger while standing on the roof and share the proposal before leaving. Back at the office, a designer can open the same project on a larger screen to fine-tune strings and cables. Everything sits in one project record alongside the lead, survey, documents and payments.
A few honest notes. Tariffs, specific yields and equipment specs in PitchSun's library are researched approximations and are flagged for you to verify, so set your DISCOM tariffs and use datasheet values for your modules and inverters. Google roof detection depends on coverage for the address; satellite tracing works wherever imagery is available.
Plans and early access
The free Starter plan includes manual roof layout. One-click roof detection and shading analysis are included in Pro, at early-access pricing of ₹999 per user per month billed yearly or ₹1,299 monthly, excluding GST. Business adds commercial and industrial projects, with custom pricing. Details are on the pricing section.
PitchSun is in early access and we are onboarding Indian installers in batches. Join the waitlist and we will set up your branding and price list with you, so your first design turns into your first proposal on day one.
Frequently asked questions
Can PitchSun design a rooftop solar system from satellite imagery?
Yes. You can trace the roof over satellite imagery, or use one-click roof detection, which reads Google Solar API data to draw the roof outline and find tanks, staircase rooms, parapets and nearby trees. Heights come from satellite data, so confirm tank and parapet heights at the site survey.
How does the solar shading analysis work?
PitchSun ray-traces shade for every module across 12 representative days of the year in 30-minute steps, against obstructions, parapets and other panel rows. It runs in the background in your browser, so a design with 300+ modules takes a few seconds.
Where does the generation estimate come from?
Yield comes from PVGIS 5.3 (ERA5 weather data, horizon-aware) for the roof's location, tilt and azimuth. If PVGIS is unavailable, PitchSun falls back to a state-average specific yield with an Indian monthly profile.
Does it handle elevated structures and tin-shed roofs?
Yes. The auto-layout supports RCC elevated, low-rise and tin-shed structures, and uses winter-solstice sun angles to space rows so they don't shade each other. Pitched roofs picked up by roof detection switch to flush mount along the main roof segment.
Does the design software do string sizing and the SLD?
Yes. PitchSun checks string sizes against the inverter's voltage limits, sizes DC and AC cables by voltage drop using run lengths from the design, and draws a single-line diagram automatically. The SLD is in English for now.
Is the solar design tool included in the free plan?
The free Starter plan includes manual roof layout. One-click roof detection and shading analysis are part of Pro, at early-access pricing of ₹999 per user per month billed yearly, excluding GST. PitchSun is in early access, so join the waitlist to get set up.