Our Mission
India is in the middle of a rooftop solar revolution. The PM Surya Ghar scheme has allocated ₹75,021 crore to put solar panels on one crore households by 2027. But most homeowners still can't answer the simplest question: “How much will I actually save?”
The solar industry is plagued by misleading claims, inflated savings projections, and opaque pricing. Installers promise “zero bill” without considering your actual tariff slab, roof orientation, or panel degradation. Homeowners end up overpaying by ₹30,000–₹80,000 because they lack transparent data.
SolarAudit was built to fix this. Our calculator uses real tariff data from every major DISCOM in India, combined with the latest 2026 PM Surya Ghar subsidy slabs, to produce an accurate ROI projection tailored to your specific state, bill amount, and roof area. No hidden math. No inflated promises. Just verified numbers you can trust.
Data-Driven Calculations
Every projection uses real DISCOM tariff rates, MNRE benchmark costs, and verified subsidy slabs — not industry averages.
Independently Verified
Our calculation methodology has been cross-checked against MNRE guidelines and actual installation costs across 7 states.
Built for Homeowners
We are not an installer. We don't sell panels. Our only goal is to give you accurate data so you can make the right decision.
Who We Are
SolarAudit is an independent energy research and information platform based in India. Our team consists of energy analysts, software engineers, and renewable energy enthusiasts who are passionate about making solar energy accessible and understandable for every Indian household.
We spend hundreds of hours each year tracking policy changes across all major Indian states, monitoring DISCOM tariff revisions, and updating our calculation models to reflect the latest ground reality. When the PM Surya Ghar subsidy rates were revised in early 2026, we were among the first platforms to update our engine.
Our editorial team independently reviews and tests every product recommended in our Solar Store and Guides. We only recommend products that meet our quality standards and are verified for Indian weather conditions.
Our Data Sources
Transparency is non-negotiable. Here are the exact sources that power our calculator:
MNRE (Ministry of New & Renewable Energy)
Official benchmark costs, approved panel/inverter lists, and subsidy slab structure for PM Surya Ghar 2026.
State DISCOM Tariff Orders
We track retail tariff rates from MSEDCL, BESCOM, UPPCL, TPDDL, DGVCL, TNEB, and BSES for accurate bill calculations.
ISRO / IMD Solar Irradiance Data
Peak sun-hour data for each state is sourced from Indian Meteorological Department and satellite irradiance maps.
On-Ground Verification
We cross-reference our projections with actual installation data from homeowners across Maharashtra, Karnataka, Gujarat, and Delhi NCR.
Our Methodology
Accuracy is not a marketing claim for us — it is an engineering constraint. Our calculator produces projections that we stand behind because every input variable is sourced, dated, and traceable. Here is exactly how we build and maintain our calculation models:
Tariff Data: DISCOM Tariff Orders (Quarterly)
State electricity tariffs in India are set by State Electricity Regulatory Commissions (SERCs) and published as official tariff orders, typically once or twice per year. We track tariff orders from MSEDCL, BESCOM, UPPCL, TPDDL, BSES, TANGEDCO, GUVNL, and five other major DISCOMs. Our tariff figures are updated within 7 days of each official tariff order publication. We use the marginal tariff rate for the consumer's relevant consumption slab — not an average — because this is the actual rate at which solar generation displaces billing.
Solar Irradiance: IMD & NASA POWER Data
Peak sun hours (PSH) determine how many units a given kW of panels will generate per day. Our PSH figures are derived from the Indian Meteorological Department's Global Solar Atlas and cross-referenced with NASA's POWER project satellite irradiance data. We use a 10-year average rather than a single recent year to avoid over- or under-stating generation due to exceptional years. Seasonal variation is built into our annual totals — we do not extrapolate from summer-only data.
Subsidy Parameters: MNRE Gazette Notifications
PM Surya Ghar subsidy rates and eligibility criteria are defined in MNRE gazette notifications and updated on the pmsuryaghar.gov.in national portal. We review these against the official gazette at each revision. Our subsidy calculator uses the tiered structure (₹30,000/kW for the first kW, ₹18,000/kW for the third kW, capped at ₹78,000) exactly as defined in the notification, not a simplified version. State-specific supplements (UPNEDA, Delhi GBI) are sourced from respective state nodal agencies.
Degradation & Maintenance: IEC 61215 Standards
Panel degradation rates in our calculator (0.5% per year for Mono-PERC, 0.7% for polycrystalline) are based on IEC 61215 accelerated testing standards and are consistent with published degradation studies from NREL and CSIRO on Indian-market panels. We model one inverter replacement at year 10–12 in our 25-year projections. Our maintenance cost estimates are based on contractor rates collected from markets in Mumbai, Bengaluru, Lucknow, and Ahmedabad.
Cross-Verification: On-Ground Installation Data
We cross-check our projections against self-reported generation data shared by homeowners in our network across Maharashtra, Karnataka, Gujarat, Delhi NCR, and Tamil Nadu. Where actual generation consistently deviates from our model by more than 5%, we investigate and update either the irradiance input or the system loss factor used in the calculation.
Affiliate Disclosure
SolarAudit is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.in. When you purchase a product through our links, we earn a small commission at no extra cost to you. This revenue helps us keep our calculator free and our data up-to-date.
Our editorial recommendations are never influenced by affiliate partnerships. We recommend products based solely on quality, durability, and value for Indian conditions. If a product doesn't meet our standards, it doesn't appear on our platform — regardless of commission rates.
Editorial Independence Policy
Our editorial content — guides, calculator methodology, product reviews, and policy analysis — is produced independently of any commercial relationship. The following rules govern our editorial process:
Corrections Policy
Solar policy, DISCOM tariffs, and subsidy rates change frequently. If you find an error in any figure on this site — a tariff rate that has been revised, a subsidy amount that has changed, or a factual inaccuracy in any guide — please report it at contact@solaraudit.vercel.app with a link to the official source. We review all correction requests within 48 hours and update the relevant page if the correction is verified. We believe public transparency about corrections is a mark of trustworthy publishing, not a weakness.
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