Solar Panel & Inverter Calculator
Solar Panel & Inverter Calculator — quick estimate
Find how many panels, what inverter rating and how much roof area a given solar capacity needs — plus the annual generation. Adjust the inputs, then get an engineered solar quote from our team.
Your system
Uses modern bifacial module ratings and ~1,500 units/kW/year for most of India. Final design depends on shadow analysis, string layout and DISCOM sanction.
Get an engineered solar quote — free
Our solar team will design the array, inverters and structure for your exact roof and send a precise quote. We'll attach the estimate above automatically.
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Thanks! Our solar team will send your tailored array & inverter design within one business day.
Indicative estimates only — not a binding quotation. Actual panel count, inverter and yield depend on the module, roof geometry, shading, tilt and DISCOM policy.
Questions engineers and CFOs ask
How many solar panels do I need for a 100 kW plant?
At 540 Wp per module a 100 kW system needs about 186 panels; at 590 Wp it needs about 170. Higher-wattage modules mean fewer panels, fewer mounting points and less cabling, which is why module selection changes structural cost as much as it changes panel count. The calculator updates all three figures as you change the wattage.
Why is the inverter rating smaller than the panel capacity?
Deliberately. Modules rarely deliver their full rated output — irradiation, temperature and soiling see to that — so sizing the inverter at roughly 85 to 90 per cent of DC capacity keeps it operating in its efficient band for more hours and costs less. The resulting DC-to-AC ratio is shown so you can check it against what a vendor has quoted you.
What DC-to-AC ratio should I aim for?
Around 1.1 to 1.3 suits most Indian C&I rooftops. Below 1.1 you are paying for inverter capacity that will almost never be used. Above about 1.3 you begin clipping meaningful generation on clear days. The right point within that band depends on your site's irradiation profile and whether you are chasing peak output or annual units.
Does the panel count include spare or replacement modules?
No. It is the working array only. Projects normally carry a small spare stock, and the exact number depends on your O&M agreement and the module warranty terms, so it is agreed at contract stage rather than assumed here.
Got your number — what next?
A calculator gives you a first figure. These take it further.
The work itself
Read before you specify
The terms behind it
Delivered work with this scope
- Turnkey MEP & Solar for Consern Pharma— Consern Pharma
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Need an exact BOQ, rate analysis or measurement sheet?
This is a quick engineering estimate. For tendering, billing or audit, our QS & estimation team prepares an item-wise BOQ, rate analysis and a verified measurement sheet to IS / CPWD norms — backed by 15+ years and ISO 9001:2015 quality processes.