DECISION GUIDES
Solar, Compared Honestly
Every solar decision comes down to an either/or. These 10 comparisons give the verdict first, then the criteria table, then a plain rule for which option fits your situation — with no product being sold at the end.
Monocrystalline vs Polycrystalline PanelsMonocrystallinevsPolycrystallineMonocrystalline wins decisively and the debate is effectively over in India. Mono panels deliver 20–22.5% efficiency against poly’s 15–17%, need roughly 25–30% less roof area for the same output, and now cost about the same per watt. Treat any quote built on polycrystalline as old stock being cleared, not a bargain.TOPCon vs Mono PERC PanelsTOPConvsMono PERCTOPCon is the better buy where available and price-competitive: 1–1.5% higher efficiency, slower degradation (≈0.40%/year vs 0.55%), better heat behaviour, and typically a 30-year performance warranty against PERC’s 25. Mono PERC remains a perfectly sound purchase — it is proven, widely stocked, and marginally cheaper.On-Grid vs Off-Grid vs Hybrid SolarOn-GridvsHybridOn-grid is the right choice for most Indian homes: cheapest per kW, eligible for PM Surya Ghar subsidy, and the fastest payback — but it gives no backup during a power cut. Choose hybrid only if outages genuinely disrupt your life; the battery bank typically adds 40–70% to system cost. Off-grid makes sense only where there is no reliable grid at all.CAPEX vs RESCO (OPEX) Solar ModelCAPEX (Own It)vsRESCO / OPEX (PPA)CAPEX delivers substantially higher lifetime savings — you own the asset and keep every unit after a 3–5 year payback — and is the right answer whenever capital is available, especially for tax-paying businesses that can claim accelerated depreciation. RESCO wins when capital is unavailable or the organisation genuinely cannot own and maintain an asset, trading roughly 40–60% of lifetime savings for zero investment and zero responsibility.Net Metering vs Gross MeteringNet MeteringvsGross MeteringNet metering is better for almost every self-consuming rooftop owner: your solar offsets units you would have bought at retail tariff, so each unit is worth ₹6–12. Gross metering sells all generation to the DISCOM at a fixed feed-in tariff — usually below retail — which only makes sense when you consume little of what you generate.Lithium (LiFePO₄) vs Lead-Acid BatteriesLithium (LiFePO₄)vsLead-Acid (Tubular)Lithium wins on lifetime cost for anything cycling daily: it delivers ~90% of its rated capacity against lead-acid’s ~50%, lasts 3–5× more cycles, and needs no maintenance. Lead-acid remains defensible only for rarely-used standby backup where the lower upfront price dominates the decision.String Inverter vs MicroinvertersString InvertervsMicroinvertersA string inverter is the right choice for most Indian rooftops: significantly cheaper per watt, simpler to service, and proven at every scale. Microinverters earn their premium on genuinely complex roofs — multiple orientations or unavoidable shading — where per-panel independence recovers more energy than the extra cost.GI Steel vs Aluminium Mounting StructuresHot-Dip Galvanised SteelvsAluminiumHot-dip galvanised steel is the cost-effective default for most Indian rooftops and ground mounts, provided the coating is genuinely 80+ microns per IS 4759. Aluminium costs more but wins decisively in coastal and high-humidity environments, and where structure weight is constrained by the roof.Bifacial vs Monofacial PanelsBifacialvsMonofacialBifacial panels are worth the premium only when mounting lets them work: elevated structures over light-coloured surfaces genuinely deliver 5–11% extra generation. Flush-mounted on a tin shed or a dark terrace, the rear face contributes almost nothing and the premium is wasted. The mounting decision, not the panel, determines the answer.Solar vs Diesel GeneratorSolarvsDiesel GeneratorSolar and diesel are not really competitors — solar produces cheap daytime energy at roughly ₹2.5–4 per unit, while diesel provides on-demand backup at ₹18–25 per unit. The correct answer for most Indian facilities is solar for energy cost and a DG (or battery) retained purely for outage backup, with solar steadily displacing DG running hours.