Science & Technology
Energy Resources
Energy Resources — Quick Revision
One-page CGPSC quick revision for Energy Resources: energy technologies, storage, hydrogen and nuclear facts in tables for last-minute Prelims and Mains.
Conventional, renewable, storage, hydrogen and nuclear technology on one page. For explanations, go back to the chapter. For locations, states and plants, see Minerals and Energy Resources (Geography).
How to use this sheet
Scan it top to bottom in the week before Prelims. Bold entries are the facts examiners return to most often. Figures are dated; check current affairs for newer ones before Mains.
India’s Energy Numbers (as of July 2026 unless stated)
| Item | Figure |
|---|---|
| Total installed capacity | ~552 GW |
| Non-fossil share | ~300.5 GW, over 54%; crossed 50% in June 2025 |
| Solar / wind / hydro / bio | ~164.6 GW / ~58 GW / ~57 GW / ~11.8 GW |
| Nuclear | 24 reactors, 8,780 MW, 7 sites (NPCIL) |
| Pumped storage | 10 PSPs, ~7,425.6 MW operating (May 2026); Pinnapuram 1,680 MW largest |
| Crude import dependence | ~89% (2025-26) |
| 2030 target | 500 GW non-fossil (COP26); net zero 2070 |
| Nuclear target | 100 GW by 2047 |
Conventional Technology
| Fact | Detail |
|---|---|
| 1 unit | 1 kWh = 3.6 MJ |
| Capacity vs generation | Non-fossil leads capacity; coal leads generation |
| Thermal plant | Rankine cycle: boiler → turbine → generator → condenser |
| Critical point of water | ~374 °C, 22.1 MPa |
| Efficiency | Subcritical ~33–36%; supercritical ~38–40%; USC ~42%+ |
| CG supercritical | Sipat Stage-I 3 × 660 MW; Lara 2 × 800 MW |
| ESP / FGD | Fly ash / SO₂ → gypsum |
| Fly ash rule | MoEFCC, 31 Dec 2021: 100% utilisation; legacy ash by 2031 |
| Coal gasification | Syngas = CO + H₂; 100 MT by 2030; ₹8,500 cr (Jan 2024); ₹37,500 cr (13 May 2026) |
| Refinery | Lightest at top: LPG, petrol, naphtha, kerosene, diesel, lubricants, fuel oil, wax, bitumen |
| Octane / cetane | Petrol anti-knock / diesel ignition |
| BS-VI | 1 April 2020; 10 ppm sulphur |
| CNG / LNG / LPG | Compressed methane / methane at −162 °C (~600× smaller) / propane + butane |
| Odorant | Ethyl mercaptan |
| Hydro power | \( P = \rho g Q H \eta \) |
| Turbines | Pelton high head · Francis medium · Kaplan low |
| Small hydro | Up to 25 MW; large hydro counted as RE since March 2019 |
Renewable Technology
| Fact | Detail |
|---|---|
| Solar PV | Photovoltaic effect, p–n junction, silicon; gives DC → inverter |
| Single-junction limit | ~33% (Shockley–Queisser) |
| Cell types | Mono, poly, thin-film (CdTe, CIGS, a-Si), perovskite, bifacial |
| CSP | Mirrors → heat → steam turbine; heliostats; molten salt storage |
| Wind power | \( P = \tfrac{1}{2}\rho A v^3 \); double speed → 8× power |
| Betz limit | 16/27 ≈ 59.3% |
| Offshore wind | 30 GW by 2030 target; VGF ₹7,453 cr for 1 GW (June 2024) |
| Biogas | Anaerobic digestion; methane ~50–70% + CO₂ |
| CBG | Purified biogas (>90% methane); SATAT 2018; GOBARdhan 2018 |
| Biofuel generations | 1G food · 2G residue (Panipat 2G ethanol) · 3G algae · 4G engineered |
| Biodiesel | Transesterification; Jatropha, used cooking oil |
| Ethanol | E20 reached 2025 |
| Geothermal | Radioactive decay; binary cycle; Tattapani (Balrampur, CG); policy 15 Sep 2025; no commercial plant |
| Tidal / OTEC | High tidal range (Khambhat) / ~20 °C difference (Kavaratti LTTD) |
Storage and Hydrogen
| Fact | Detail |
|---|---|
| Duck curve | Midday dip, steep evening ramp |
| Pumped storage | Pump up when cheap, generate at peak; ~70–80% round trip |
| Li-ion | Graphite anode; NMC (EVs) or LFP (grid; no cobalt or nickel) |
| Sodium-ion / flow | Abundant sodium / liquid electrolytes in tanks (vanadium redox) |
| PLI ACC | May 2021; ₹18,100 cr; 50 GWh |
| BESS VGF | 2023 scheme; ₹5,400 cr for 30 GWh (June 2025) |
| Battery Waste Management Rules | 2022; EPR |
| Fuel cell | H₂ + O₂ → electricity + water; no combustion; PEM for vehicles |
| Electrolyser | Reverse of fuel cell: alkaline, PEM, solid oxide |
| Hydrogen colours | Grey (gas, SMR) · Blue (gas + CCS) · Brown (coal) · Turquoise (pyrolysis) · Pink (nuclear) · Green (RE electrolysis) |
| Green Hydrogen Mission | 4 Jan 2023; ₹19,744 cr; 5 MMT/yr by 2030; ~125 GW RE; SIGHT |
| Green hydrogen standard | ≤ 2 kg CO₂e per kg H₂ (Aug 2023); BEE accredits |
| Hydrogen hubs | Deendayal (Kandla), V.O. Chidambaranar (Tuticorin), Paradip (Sept 2025) |
| CG link | Katghora: first lithium block auctioned (June 2024) |
Nuclear
| Fact | Detail |
|---|---|
| Natural uranium | ~99.3% U-238, ~0.7% U-235 |
| Fission | ~200 MeV per U-235 fission; 2–3 neutrons; chain reaction; criticality k = 1 |
| Fusion | D + T → He + n + 17.6 MeV; tokamak; ITER at Cadarache, France; India member since 2005 |
| Fissile / fertile | U-235, Pu-239, U-233 / U-238, Th-232 |
| Moderator | Slows neutrons: heavy water, light water, graphite |
| Control rods | Absorb neutrons: boron, cadmium, hafnium |
| PHWR | Natural U + heavy water; India’s workhorse; 700 MW units (Kakrapar first) |
| BWR / VVER | Tarapur (1969, first) / Kudankulam (largest) |
| FBR | No moderator; liquid sodium coolant; MOX fuel |
| Fuel cycle | Jaduguda, Tummalapalle (UCIL) → NFC Hyderabad → reactor → reprocessing (Trombay, Tarapur, Kalpakkam) → vitrification |
| India’s cycle | Closed (reprocessing) |
| Three stages | PHWR (nat. U → Pu) → FBR (Pu, breeds Pu and U-233) → thorium + U-233 |
| FBTR / PFBR / KAMINI | 1985 / 500 MWe, BHAVINI, criticality 6 April 2026 / U-233 fuelled, 30 kW |
| Thorium | Monazite sands (Kerala, Odisha, AP, TN); ~11.93 MT monazite (AMD) |
| Institutions | AEC 1948; DAE 1954; BARC (name from 1967); AERB 1983; NPCIL 1987 |
| Nuclear Energy Mission | Budget 2025-26; ₹20,000 cr SMR R&D; 5 SMRs by 2033; 100 GW by 2047 |
| SMRs | BSR (220 MW PHWR, captive for steel and aluminium); BSMR-200; SMR-55 |
| SHANTI Act 2025 | Assent 20 Dec 2025; replaces AEA 1962 + CLNDA 2010; private entry; statutory AERB; operator liability |
| Accidents | Three Mile Island 1979; Chernobyl 1986 (RBMK); Fukushima 2011 |
Don’t Confuse
| This | vs | That |
|---|---|---|
| CNG, LNG: methane | vs | LPG: propane + butane |
| Octane: petrol | vs | Cetane: diesel |
| ESP: fly ash | vs | FGD: SO₂ |
| Solar PV: light → DC | vs | CSP: light → heat → turbine |
| Biogas: CH₄ + CO₂ (anaerobic) | vs | Producer gas / syngas: CO + H₂ |
| Tidal: tidal range | vs | OTEC: temperature difference |
| Fuel cell: makes electricity | vs | Electrolyser: makes hydrogen |
| Green H₂: RE electrolysis | vs | Blue H₂: gas + carbon capture |
| Moderator: slows neutrons | vs | Control rods: absorb neutrons |
| Fissile (U-235, Pu-239, U-233) | vs | Fertile (U-238, Th-232) |
| PHWR: natural U | vs | PWR/BWR: enriched U |
| Tarapur: first | vs | Kudankulam: largest |
| Capacity share | vs | Generation share |
Favourite MCQ trap
“Thorium can be used directly as reactor fuel.” Wrong. Thorium-232 is fertile: it must absorb a neutron and decay to U-233 before it can sustain fission. That conversion is why India needs stage 2 fast breeders before stage 3.
Second favourite trap
“Over half of India’s electricity now comes from non-fossil sources.” Wrong. Over half of installed capacity is non-fossil (July 2026), but coal still generates most of the electricity, because solar and wind have low capacity factors.
Advertisement