Revision summary
Solar PV has no plant fuel, low operational water, and modular scale versus coal thermal. It cuts operating emissions and can generate near load on rooftops. It is variable: nights and clouds still need storage or conventional firm power. JNNSM, SECI parks, KUSUM, rooftop schemes, and RPOs are the main domestic initiatives. ISA is the international arm; 175 GW by 2022 was the target frame of that period.
Model answer
Copper italics in this answer — like this — are the key facts. Each one is unpacked in the Facts & figures rail.
Introduction
Solar electricity turns irradiance into current through photovoltaic cells or, less often in India, concentrated solar heat. Conventional generation here means mainly coal thermal, plus gas, large hydro, and nuclear. Solar’s benefits are fuel-free kilowatt-hours and modular scale. Its limits are night, clouds, land, and a grid that still needs firm power. Policy since the National Solar Mission has tried to buy down that gap.
Body
Benefits versus conventional generation
- No fuel cycle at the plant: no coal rakes, no imported gas price spike, no mine-to-ash chain. Operating emissions at the panel are effectively zero (manufacturing and land still have a footprint).
- Modular and quick: a megawatt of solar can be added in months; a pit-head thermal plant is years of clearances and boilers.
- Distributed option: rooftop and agricultural pumps can generate at the load, cutting some T&D loss that conventional central stations pay.
- Water: PV uses little operational water compared with thermal cooling towers — material in stressed basins.
- Energy security: sunlight is domestic; coal is largely domestic too, but solar diversifies away from a single dirty stock and from imported thermal coal in some plants.
- Health and climate: displacing coal reduces local air pollution and CO2 per kWh, which is the public-health case, not only a climate pledge.
Honest contrast — what conventional still does better
- Firm, dispatchable power: coal, hydro, and nuclear follow load; solar is variable. Without storage, gas, hydro, or demand response, the grid still leans on conventional capacity after sunset.
- Land and materials: utility solar needs acres and imported cells/modules in many years; thermal is compact at the plant but huge if mines and ash ponds are counted.
- Inertia and system stability: synchronous machines help the grid; inverters need ancillary-market design.
- So the benefit is real on energy and emissions; it is not a complete substitute on reliability unless storage and transmission are built.
Government initiatives
- Jawaharlal Nehru National Solar Mission (2010) under NAPCC: the original reverse-auction, RPPO, and park architecture.
- SECI tenders, solar parks, and interstate transmission support that crashed tariffs through competition.
- KUSUM: solarise pumps, grid-connected agro-feeders, and farmer as producer — the rural initiative.
- Rooftop solar schemes (residential incentives, later phase changes), CPSU programmes, and defence/railway solarisation.
- Renewable Purchase Obligations, waiver of ISTS charges for solar/wind in specified windows, and green energy corridors.
- International Solar Alliance (co-founded by India): diplomacy and standardisation, not a domestic kWh.
- At the 2020 horizon, India was pursuing a 175 GW renewable target by 2022 (100 GW solar in that package) and signalling a larger 450 GW non-fossil path — targets, not already-installed facts.
- Complementary: PLI for high-efficiency modules (announced around this industrial-policy wave) to cut import dependence — name it as industry policy, not as a 2010 Mission clause.
To make the benefit stick
- Pair solar with storage, flexible coal/hydro, and market reforms (ramping, ancillary services).
- Do not count diesel-backup rooftop as a clean win.
Flow diagram
flowchart TD SUN[Sunlight] --> PV[PV electricity] PV --> B[No fuel low water modular] COAL[Coal thermal] --> F[Firm power fuel ash] POL[JNNSM SECI KUSUM RPO] --> PV ST[Storage transmission] --> G[Grid-worthy solar]
Conclusion
Solar electricity beats conventional thermal on fuel, water, modularity, and operating emissions. It loses on night-time firmness unless storage and the grid catch up. Government initiatives run from the National Solar Mission and SECI parks through KUSUM, rooftop programmes, RPOs, and the International Solar Alliance. The benefit is a cleaner kWh; the system still needs conventional or stored power when the sun is down.
Quick related
Students also ask
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"Access to affordable, reliable, sustainable and modern energy is the sine qua non to achieve Sustainable Development Goals (SDGs)".Comment on the progress made in India in this regard. (150 Words, 10 Marks).
Next question on this syllabus topic (2018 · Q1). View answer →
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Can solar replace all coal plants today?
Not as firm 24-hour power without storage and transmission. It can displace many daytime thermal units.
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Is rooftop always better than a park?
Rooftop saves land and some losses. Parks win on tariff and speed. India needs both.
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