Solar Carbon Offset Calculator
Solar Carbon Offset Calculator — quick estimate
Put a number on the environmental case: tonnes of CO₂ your plant keeps out of the air each year, computed the way Scope 2 reductions actually are — displaced grid units times the grid emission factor.
Your plant
Uses 1,500 units/kWp/yr and the CEA grid emission factor of 0.71 kg CO₂/kWh (CO₂ Baseline Database). Trees-equivalent uses ~20 kg CO₂/tree/yr — a communication figure, not science.
Get the plant behind the tonnes — free proposal
We'll size the system for your facility and include the metered-generation monitoring that turns this estimate into reportable Scope 2 reductions.
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Your request is in
Your request reached our team with exactly what the preview showed. If an engineer needs your drawings, bill or data, they will use the number you gave.
Indicative — filed ESG/BRSR disclosures should use metered generation and cite the CEA database version applied. The 25-year figure is before module degradation.
Questions engineers and CFOs ask
How much CO₂ does rooftop solar save in India?
Every solar unit that displaces grid power avoids roughly 0.71 kg of CO₂ — the CEA's grid emission factor, which reflects India's coal-heavy generation mix. A 500 kWp plant producing 7.5 lakh units a year therefore avoids around 530 tonnes of CO₂ annually, and the factor itself will drift down slowly as the grid gets cleaner.
Can I use these numbers in ESG or BRSR reporting?
The method is exactly right — displaced grid units times the grid emission factor is how Scope 2 reductions are computed. For a filed report you should use metered generation rather than an estimate, and cite the CEA CO₂ Baseline Database version you applied. Our O&M monitoring reports give you the metered figure per month, ready for the disclosure.
Do the trees-equivalent numbers actually mean anything?
They are a communication device, not science — we use roughly 20 kg of CO₂ absorbed per mature tree per year, a common planning figure, and real absorption varies hugely by species and age. Fine for a CSR slide to make tonnes tangible; for anything audited, report the tonnes themselves.
Does going solar earn carbon credits I can sell?
Generally not for behind-the-meter rooftop plants — the value of the green attribute is typically consumed by your own decarbonisation claim, and registering small projects for credits rarely clears the transaction costs. Larger open-access and captive structures can be different, and buyers increasingly ask who keeps the attributes — worth settling in the PPA before signing.
Got your number — what next?
A calculator gives you a first figure. These take it further.
The work itself
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One of 56 free MEPF and solar calculators on this site. Every input term is defined in the engineering glossary; the specification libraries, clearance guides and checklists for design teams are in the architects' section.
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 of estimating our own projects.