Renewable Energy & Green Technology

No Decision on Ethanol Blending Beyond E20 (The Hindu, 21-07-2026)

• Suresh Gopi, Minister of State in the Ministry of Petroleum & Natural Gas, told the Rajya Sabha on 20-07-2026 that no decision has been taken to raise the blending quantum with petrol beyond the present 20%, nor to blend ethanol with diesel for commercial use
• But the groundwork exists: in June 2026 the government exempted petrol blended with a higher quantum of ethanol — 22% to 30% — from the levy of central excise duties, to boost biofuel blending; and the Bureau of Indian Standards (BIS) has already notified the technical standards to be adhered to if such blends are rolled out commercially
• Read this against the E20 controversy above: the Ministry is holding the line at E20 while the fiscal and standards architecture for E22–E30 is quietly in place. The government's stated position is that any future decision "will be based on comprehensive scientific evaluation, vehicle compatibility studies, stakeholder consultations and the availability of adequate domestic production capacity"

India's Missing Pillar — Long-Duration Energy Storage (LDES) (The Hindu "Science", 21-07-2026 — Aedna Kurian & Ammu Susanna Jacob, CSTEP)

• The demand context: on 21 May 2026 India recorded its highest-ever peak demand of 270.8 GW during the day — about 90 GW higher than the same window in 2019. Demand peaks again at night (air-conditioning), when solar is unavailable — which is precisely the gap storage must fill
• What LDES is: technologies that store energy and discharge it as power or thermal energy over extended periods — from 8 hours to days, weeks or seasons. This distinguishes it from short-duration storage, which handles intra-day fluctuations
• The gap in India's plan: the 2026 Long-Term National Resource Adequacy Plan envisages 80 GW of battery energy storage and 94 GW of pumped hydroelectric energy storage (PHES) by FY2035-36 — but these translate to average discharge durations of only about 4 and 6 hours respectively. Enough for short-term fluctuations, not enough for prolonged adverse weather such as heatwaves
• The technology comparison (a ready-made Prelims table):

• Costs: per a Pacific Northwest National Laboratory (US DoE) study, PHES and CAES are the most cost-effective and commercially viable at present — $0.12/kWh and $0.10/kWh respectively. The LDES Council projects a significant decrease in LDES costs by 2030
• India's assets and pilots: per a 2026 Central Electricity Authority report, India's PHES potential is about 267 GW; India plans 100.8 GW of PHES by 2035-36, of which 11.6 GW is under construction. In early 2025 India commissioned a 160-MWh carbon-dioxide battery storage system at NTPC Kudgi, Karnataka (cycles CO2 between liquid and gas phases; operational life exceeding 25 years), followed by the country's first MWh-scale vanadium redox flow battery — a 3-MWh facility at NTPC, Greater Noida
• International policy models: the California Public Utilities Commission set an LDES procurement target of 2 GW, to be deployed between 2031 and 2037; the U.K. launched a financial framework guaranteeing LDES projects a minimum revenue even in poor market conditions — a cap-and-floor-style safety net to unlock investment
• Related (same edition): Bondada Engineering won an EPC package from NTPC Renewable Energy for a 100 MWh Vanadium Redox Flow Battery (VRFB) storage system at the Khavda Solar Park, Gujarat, with Delectrik Systems as technology partner — VRFB being pitched for its advantages over conventional lithium iron phosphate (LFP) systems

Mains

(Analysis, dimensions, significance, critique, policy angles — for 10/15 mark answers)

E20 — A Transition That Is an End-to-End Engineering Problem, Not a Fuel Swap (The Hindu, 20-07-2026)

• The core argument: an E20 transition is not simply about changing what goes into the tank. It is an end-to-end engineering exercise spanning refineries → logistics → storage terminals → fuel stations → vehicle manufacturers → service networks. The transition "succeeds only when every link in that chain is engineered and managed to the same standard" (Vinay Piparsania, MillenStrat Advisory; former Executive Director, Ford India). India upgraded the fuel faster than it upgraded the chain that delivers it
• Why E10 → E20 is more than doubling a number: ethanol's chemical characteristics (solvency, hygroscopicity) become more pronounced at 20%, making compatibility requirements qualitatively more demanding — not linearly so
• The attribution problem: ethanol itself may not be the culprit. Complaints plausibly stem from (a) pre-2023 vehicles never calibrated for E20, and (b) fuel-quality/contamination failures in storage and dispensing — which can independently cause injector fouling, poor drivability, pump failure and engine damage. Retail outlets report discarding hundreds of litres of water-contaminated E20 as unfit for sale
• The information-governance failure: the absence of published official data for months allowed speculation and competing claims to fill the vacuum — a textbook case of how transparency deficits erode public confidence in a sound policy. The fix flagged is coordinated communication across government, oil marketing companies, vehicle manufacturers and dealers, plus a visible commitment that genuine grievances will be investigated promptly, transparently and resolved fairly
• Distributional angle: the costs fall on owners of older vehicles — disproportionately lower-income households who cannot replace a pre-2023 car — while the benefits (energy security, farmer incomes) are diffuse and national. A just-transition question inside a green-energy policy
• Counter-balance (do not over-critique): EBP genuinely advances energy security (crude import substitution), farm incomes and emission reduction, and was delivered five years early — a rare instance of an Indian target being over-achieved. The critique is of sequencing and communication, not of the policy's direction
• Wider caution: ethanol production competes for water-intensive sugarcane and foodgrain (rice/maize) feedstock — a food-vs-fuel and water-footprint trade-off that must be weighed against the blending target (link to agriculture-food-management and land-water-resources)
• UPSC angle: Ethanol Blended Petrol Programme & energy security, biofuel policy (National Policy on Biofuels 2018, amended 2022), food-vs-fuel debate, just transition, consumer protection & regulatory transparency, technology transitions and supply-chain readiness

Long-Duration Storage: The Gap Between a Renewables Target and a Reliable Grid (The Hindu Science, 21-07-2026 — CSTEP)

• The core argument: India's clean-energy planning has optimised for capacity addition (GW of solar and wind) and, latterly, for short-duration storage to smooth the daily curve. What it has not planned for is multi-day reliability. The authors' warning is blunt: "without planning to include LDES, India's clean energy future could be forced to rest on favourable weather and market conditions" — i.e. the grid's firmness would be a matter of luck rather than design
• Why duration, not just capacity, is the right metric: 80 GW of batteries at a 4-hour average duration cannot cover a multi-day wind lull or a heatwave that simultaneously raises demand and suppresses solar output through panel de-rating and cloud cover. Reliability failures are tail events, and tail events are exactly what average-duration planning misses
• The economics have a built-in tension worth stating: the longer the period over which a technology discharges, the better its economics per unit of energy delivered — but storing more energy is itself more expensive. Consequently, for discharge durations beyond six hours, short-duration systems are unlikely to prove cost-effective, which is precisely where LDES must take over. This is the sentence to reproduce if asked why batteries alone will not do
• The four specific policy gaps identified:
• No place in the framework — LDES should be incorporated into the Ministry of Power's National Framework for Promoting Energy Storage Systems, with guidelines on deployment and grid integration. The National Electricity Plan projects capacities for battery ESS and PHES but provides no technology-specific assessments or deployment pathways for LDES
• No siting intelligence — future planning exercises should estimate LDES requirements and identify the technologies best suited to India's extreme weather and geographical conditions (PHES needs terrain and water; CAES needs salt caverns or depleted gas fields; thermal and hydrogen depend far less on site, so may suit locations where the others are impossible)
• Investment barriers — faster environmental and land clearances, transmission alignment, and clear regulatory classification are needed to unlock investment
• Incentive design — subsidies and viability-gap funding must be technology-agnostic (not pick a winner), should incentivise co-location with data centres, and as the market matures the focus must shift to long-term revenue contracts, tariff structures and procurement frameworks
• The capability gap nobody budgets for: the authors ask that dispatch centres post staff for skill enhancement and training to handle optimal dispatch, multi-day charge–discharge decisions, state-of-charge management across seasons, and coordination across storage assets. Multi-day storage is an operational and human-capital problem, not only a procurement one — a good example of institutional capacity as the binding constraint on a technology transition
• How to use this in an answer: it upgrades the standard "India needs storage for its 500 GW non-fossil target" line into a precise, three-level argument — (i) capacity is not energy, (ii) energy is not duration, (iii) duration is not dispatchability without operator skill and market design. Pairs naturally with the grid-congestion and AI/data-centre demand points already in this file
• UPSC angle: energy security and grid reliability, variable renewable integration, 500 GW non-fossil by 2030, PHES potential and siting, critical-mineral dependence of battery chemistries (a case for vanadium/CO2/thermal diversification), viability-gap funding, technology-neutral incentives, just and reliable energy transition