CEA Factor vs IEA Factor — Which Grid Emission Factor for Indian Scope 2?

The 30-second answer

For Indian regulatory reporting (BRSR / BRSR Core / SAE 3410 assurance): use CEA. The current value (V21.0, November 2025) is 0.7117 tCO₂/MWh all-India weighted average for FY 2024-25. Use the regional factor (Northern / Western / Southern / Eastern / North-Eastern) for each site where you have multi-region operations.

For international reporting (CSRD / IFRS S2 / CDP): CEA is also fine — it qualifies as a national location-based factor under the GHG Protocol Scope 2 Guidance. Use IEA only when you specifically need cross-country methodological consistency with non-Indian peer entities also using IEA.

For CBAM embedded-emissions calculations: use installation-specific actual factors where available; CEA factors are acceptable inputs subject to EC-accredited verifier review.

The side-by-side

Dimension	CEA (Central Electricity Authority, Government of India)	IEA (International Energy Agency, OECD)
Latest published value	0.7117 tCO₂/MWh all-India, FY 2024-25 (V21.0, Nov 2025)	~695 g CO₂/kWh, 2025 (Emissions Factors 2025 database, mid-2025)
Reporting cycle	Annual; published Nov-Dec; FY April-March	Annual; published mid-year; calendar years
Geographic granularity	All-India + 5 regions (Northern, Western, Southern, Eastern, North-Eastern)	Country-level only (no India regional split)
Factor variants	Operating margin, build margin, combined margin (for CDM-style projects); weighted average (for inventory)	Single national average
Underlying data	Indian power station generation data, station-by-station	IEA energy balances + IPCC default factors
Boundary	Generation at busbar; excludes inter-grid imports	National consumption-based; some loss adjustments
Regulator status (India)	Official Government of India source	International reference; no Indian regulatory standing
Used by	SEBI BRSR / BRSR Core, ICAI SAE 3410 assurance, MoEFCC CCTS, CDM Indian projects	International benchmarking; CDP; some CSRD/IFRS filings for cross-country consistency
Cost	Free; published in CEA User Guide PDF	Free for top-line figures; subscription for full Emissions Factors database
Forecast horizon	Historical only (FY 2024-25 latest in V21.0)	Includes IEA scenarios (Electricity 2026 forecasts 585 g/kWh by 2030)

Why the two values land close but not identical

The 711.7 g/kWh (CEA) vs ~695 g/kWh (IEA) gap of roughly 2-3% reflects three structural choices:

1. Boundary. CEA’s weighted-average is busbar-level generation. IEA’s national figure is derived from consumption-side energy balances with some adjustment for grid losses and net imports/exports. India is a net electricity importer at the margin in some FYs (mainly from Bhutan hydroelectric); CEA explicitly excludes that, IEA implicitly includes it.

2. Methodology. CEA aggregates actual generation data from Indian power stations — coal, gas, oil, nuclear, hydro, renewables, captive. IEA processes country fuel-consumption statistics through IPCC default factors. Two slightly different methods applied to the same underlying physical system, expected to land close but not identical.

3. Reporting year. CEA V21.0 covers FY 2024-25 (April 2024 to March 2025); IEA Emissions Factors 2025 database covers calendar year 2024. Six months of temporal misalignment can produce ~1-2% drift in a year where renewable capacity is being added rapidly.

The values are converging year-over-year as both methodologies refine and as Indian electricity emissions are tracked more granularly. For most reporting purposes, the gap is within the uncertainty range of the underlying Scope 2 calculation and does not materially affect the final emissions number.

When to use each — the decision framework

Use CEA if any of these apply:

• Reporting under SEBI BRSR or BRSR Core (mandatory for the Indian regulatory deliverable)
• Assurance engagement under SAE 3000 (Revised) + SAE 3410 — partner CA firm will expect CEA-source calculations
• Reporting under MoEFCC’s Carbon Credit Trading Scheme (CCTS)
• Multi-region Indian operations where you need the regional grid factor for each site
• Indian voluntary carbon credit projects (CDM-style methodologies use CEA operating/build/combined margins)

Use IEA if any of these apply:

• Cross-country benchmarking where peer entities use IEA for methodological consistency
• Parent group’s consolidated emissions inventory architecture is built on IEA factors and the Indian subsidiary contributes a small share
• Forward-looking scenario analysis where you need a forecasted India electricity intensity (CEA does not publish forward factors; IEA Electricity 2026 publishes 2030 forecasts)
• Specific reporting frameworks that mandate IEA (rare; most international frameworks accept either)

Use installation-specific actual factors if:

• Reporting under CBAM (the EC verifier methodology favours installation-specific over national-average where available)
• Market-based Scope 2 where you claim renewable energy purchases via PPA, REC, or green tariff — the supplier-specific contract factor is required, not CEA or IEA
• Investor due diligence where the buyer wants site-level granularity

The dual-reporting case (location-based + market-based)

For an Indian entity that purchases corporate PPAs, RECs, or signs green-tariff contracts to claim renewable energy attribution, the GHG Protocol Scope 2 Guidance requires dual reporting:

1. Location-based using CEA (for Indian regulatory) or IEA (for international consistency) — represents the grid average the entity would have drawn if no contract existed.
2. Market-based using the supplier-specific or contract-specific factor — represents the actual emissions attributable to the entity’s electricity consumption after accounting for green attributes purchased.

For BRSR Core assurance, the location-based number is the primary disclosure; the market-based number is a supplementary disclosure that some listed entities include in their BRSR Section C narrative. The assurance practitioner verifies both calculations under SAE 3410 if both are claimed.

What BatchWise does on Scope 2 calculation

BatchWise is a coordination platform. We do not sign assurance reports — every signed deliverable comes from an ICAI-empanelled partner CA firm under their own DSC. For Scope 2 calculations specifically, the workflow is:

1. Inventory data collection. Site-level electricity consumption (kWh) by grid region for each Indian operation; PPA / REC contract terms for any market-based claims.
2. Factor application. CEA regional grid factor applied per site (location-based); supplier-specific contract factor applied for market-based.
3. Aggregation and disclosure. Consolidation across sites; disclosure in BRSR Section C narrative + BRSR Core attribute on GHG Emission Intensity per Revenue.
4. Assurance. Partner CA firm reviews the Scope 2 calculation as part of the broader BRSR Core engagement under SAE 3000 (Revised) + SAE 3410.

For the fixed-price BRSR Core Assurance engagement (₹75,000, 72-hour SLA), Scope 2 calculation is included in the scope. For multi-site or complex configurations, scope is reviewed during the consult intake.

Common confusions

“CEA publishes multiple values — which one do I use?” For Scope 2 inventory reporting, use the weighted-average factor (which includes renewables + captive + non-fossil) at the regional level for each site. The operating-margin / build-margin / combined-margin variants are for CDM-style project additionality calculations, not corporate inventory.

“My audit firm uses IEA — is that a problem?” Not strictly. Both CEA and IEA are accepted as national location-based factors. But for the Indian BRSR Core regulatory deliverable, CEA is the convention; if your firm uses IEA, expect a reconciliation requirement at the assurance stage.

“I’m a small entity, do I need to track grid region?” If you have operations in only one grid region (say all sites in the Western grid), use the Western regional factor and skip the all-India weighted average. The regional factor is more accurate. For multi-region operations, track each site separately.

“CEA V21.0 covers FY 2024-25 — what do I use for FY 2025-26 reporting?” CEA’s V21.0 is the latest published; for FY 2025-26 inventory reporting, V21.0 is the current best available source. CEA V22.0 (covering FY 2025-26) is expected in Nov-Dec 2026. Some assurance practitioners prefer using the most-recently-published factor at the time of report signing; others prefer the factor for the reporting period. Confirm with your partner CA firm.