Carbon Accounting
The discipline that powers every ESG report. Master the GHG Protocol, all 15 Scope 3 categories, financed emissions via PCAF, and SBTi target-setting — with the exact answers UAE interviewers expect.
- GHG Protocol — the foundational standard
- Scope 1 — direct emissions
- Scope 2 — purchased energy (location vs market)
- Scope 3 — all 15 categories
- Emission factors hierarchy
- Organisational boundaries
- Base year recalculation policy
- PCAF — financed emissions
- SBTi — Science Based Targets
- Walkthrough: building a real GHG inventory
GHG Protocol — the foundational standard
The GHG Protocol is the global standard-setter (WBCSD + WRI). It's the methodology that ISSB IFRS S2 mandates, that PCAF references, and that every credible carbon inventory uses.
The suite of standards
| Standard | Year | What it covers |
|---|---|---|
| Corporate Accounting & Reporting Standard (Corporate Standard) | 2004 + 2015 amendment | Base for org-level inventories. Defines Scope 1, 2, 3. |
| Scope 2 Guidance | 2015 | Introduced dual reporting — location-based + market-based. |
| Corporate Value Chain (Scope 3) Standard | 2011 | 15 categories of indirect value chain emissions. |
| Product Life Cycle Standard | 2011 | Cradle-to-grave product carbon footprint. |
| Mitigation Goal Standard | 2014 | How to set + track corporate climate goals. |
| Project Protocol | 2005 | Project-level emissions reductions (carbon credits). |
Land Sector & Removals Guidance (LSRG) finalised March 2024. Scope 2 + Scope 3 + Corporate Standard updates expected late 2025/early 2026. Stay current — interviewers test this.
Scope 1 — Direct emissions
Definition: Direct emissions from sources owned or controlled by the company.
Four sub-categories
- Stationary combustion — boilers, furnaces, gen-sets, kilns
- Mobile combustion — fleet vehicles, ships, planes (if owned)
- Process emissions — chemicals, cement clinker calcination, refrigerant production
- Fugitive emissions — HFC refrigerant leaks from chillers, SF6 from electrical switchgear, methane from oil & gas operations (compressors, pipelines, venting)
Sector-specific examples
🛢️ Oil & Gas (ADNOC)
Flaring, venting, fugitive methane from compressors/pipelines, process CO2 from gas processing (acid gas removal at Habshan).
🏢 Real Estate (Aldar, Emaar)
Gas-fired boilers, diesel gen-sets, refrigerant top-ups in chillers, fleet emissions for facilities/security.
🏦 Financial Services (FAB, ENBD)
Office HVAC refrigerant leaks, company fleet, back-up gen-sets. Usually small absolute Scope 1 vs Scope 3 financed.
Scope 2 — Indirect emissions from purchased energy
Definition: Indirect emissions from purchased electricity, steam, heating and cooling.
For UAE: largely grid electricity (DEWA, EWEC, FEWA, SEWA) and district cooling (Empower, Tabreed, Emicool — major Scope 2 stream in UAE real estate).
This is THE most-asked carbon accounting question in UAE interviews. Get it wrong and you're out.
Dual reporting (mandatory since 2015 Scope 2 Guidance)
| Method | What it uses | Example for UAE |
|---|---|---|
| Location-based | Average grid emission factor for the geography where consumption occurs | UAE 2024 grid factor ≈ 0.42 tCO2e/MWh (declining as Barakah + solar scale) |
| Market-based | Emission factors from contractual instruments — PPAs, RECs/I-RECs, green tariffs, supplier-specific factors | UAE: I-RECs (since 2017, retired via Evident registry) + DEWA Shams Dubai green tariff + solar park PPAs |
Both must be reported under GHG Protocol Scope 2 Guidance (2015) — "dual reporting" is mandatory for any company making market-based claims.
RECs/I-RECs only reduce market-based Scope 2, never location-based. They must meet the 8 Scope 2 Quality Criteria:
- Conveys energy attribute information (with claim language)
- Is the only instrument carrying the attribute
- Is tracked + redeemed only once (no double counting)
- As close as possible to consumption period (vintage)
- Sourced from same market boundary as electricity consumed
- Generated from production after a defined date
- Not exceeding the consumption it offsets
- Used + claimed only by the consumer
Scope 3 — All 15 Categories
Definition: All other indirect emissions in the value chain. The biggest, hardest, and most material category for most companies.
Upstream (Categories 1–8)
| # | Category | Notes |
|---|---|---|
| 1 | Purchased goods & services | Often largest for FS/retail. Embodied carbon of cement, steel, cloud services. |
| 2 | Capital goods | Fixed assets — building construction, machinery purchases. |
| 3 | Fuel- and energy-related activities | Well-to-tank + grid T&D losses (NOT in S1/S2). |
| 4 | Upstream transportation & distribution | Logistics for inputs. |
| 5 | Waste generated in operations | Landfill, recycling, treatment. |
| 6 | Business travel | Flights, hotels, rental cars (commercial). |
| 7 | Employee commuting | Daily commute + WFH energy use. |
| 8 | Upstream leased assets | Where company is lessee and not in S1/S2. |
Downstream (Categories 9–15)
| # | Category | Notes |
|---|---|---|
| 9 | Downstream transportation & distribution | Logistics post-sale. |
| 10 | Processing of sold products | If your product is processed further. |
| 11 | Use of sold products | Largest for O&G, autos, fossil fuel utilities. ADNOC's Scope 3 dwarfs S1+S2 by 8–10×. |
| 12 | End-of-life treatment | Disposal of sold products. |
| 13 | Downstream leased assets | Where company is lessor. |
| 14 | Franchises | Where franchisor is reporting company. |
| 15 | Investments — financed emissions | Banks, asset managers, insurers — see PCAF below. |
"For an oil & gas company, what's the biggest Scope 3 category?"
→ Category 11 (Use of Sold Products) — typically 80–90% of total footprint. ADNOC's Scope 3 is ~8–10× their Scope 1+2.
"For a bank?" → Category 15 (Investments / financed emissions) — 90%+ of total. Use PCAF methodology.
Materiality screening
GHG Protocol requires identifying which categories are material — typically by:
- Spend — high-spend categories likely high-emission
- Emission intensity — high-intensity sectors regardless of spend
- Influence — categories where you can drive reduction
- Stakeholder concern — what investors/customers expect to see
Emission factors — sources & hierarchy
Recognised sources to name in interviews:
🇬🇧 DEFRA (UK BEIS)
Annual updates each June. Gold-standard for fuel/transport/waste/water/material factors. Most widely used in UAE consultancy work.
🇺🇸 EPA
eGRID for power, GHG Inventory factors for fuels. US-centric but methodologically rigorous.
🌍 IEA
Country-level grid emission factors (paid). The default for international Scope 2 location-based. IEA "Emissions Factors" published annually.
🌡️ IPCC Guidelines
2006 + 2019 refinement. Scientific basis for emission factors and GWPs. Used in national inventories.
🏛️ IFI Harmonised Framework
Used by World Bank, ADB, EBRD for project finance GHG accounting. You'll see this on infrastructure / sustainable finance roles.
🇦🇪 MOCCAE (UAE-specific)
Country-specific factors (water, electricity by emirate) in the UAE National GHG Inventory. Use when reporting to MOCCAE National Registry.
GWP convention — get this right
- CH4 fossil = 27.9
- CH4 non-fossil = 27.0
- N2O = 273
- SF6 = 25,200
AR6 superseded AR5 (CH4 = 28). AR4 (CH4 = 25) is years out of date. Old reports may still use AR4 — flag this if reviewing legacy inventories.
Organisational boundaries
GHG Protocol gives 3 consolidation choices:
| Approach | Definition | When to use |
|---|---|---|
| Equity share | Account for emissions per % of equity owned | Investment portfolios, financial reporting alignment |
| Operational control | Account for 100% emissions of operations where you have authority to introduce/implement operating policies | Most common — default for industrial groups |
| Financial control | Account for 100% emissions where you have ability to direct financial/operating policies for economic benefit | Holdings/investment vehicles |
Joint ventures are the classic test case. ADNOC Gas vs ADNOC Group reporting differs by boundary choice. Choice must be disclosed and applied consistently across all categories and years.
Base year recalculation policy
GHG Protocol requires a base year (typically a fixed historical year — 2019, 2020, or first inventory year). This is the single most-asked technical question in carbon accounting interviews.
When to recalculate
- Structural changes (M&A, divestitures, outsourcing/insourcing) — material if exceed your significance threshold (commonly 5%)
- Changes in calculation methodology
- Updated emission factors or GWP updates (e.g. AR5 → AR6)
- Discovery of significant errors
When NOT to recalculate
- Organic growth/decline — production going up or down within existing operations is NOT a structural change
"What's your base year recalculation policy?"
"We recalculate the base year inventory for structural changes exceeding our 5% significance threshold, methodology changes, and discovered errors above 5% of total inventory. We do not recalculate for organic growth or production changes within existing operations. The policy is documented in our methodology note and applied consistently — the most recent recalculation was for the AR5 → AR6 GWP update which raised our methane figures by ~3%."
PCAF — Partnership for Carbon Accounting Financials
What it is: Industry-led initiative (founded 2015 in Netherlands, now global). Develops the Global GHG Accounting & Reporting Standard for the Financial Industry — the methodology the GHG Protocol Scope 3 Category 15 explicitly references.
Part A — Financed Emissions (7 asset classes)
- Listed equity & corporate bonds
- Business loans & unlisted equity
- Project finance
- Commercial real estate
- Mortgages
- Motor vehicle loans
- Sovereign debt (added 2022)
Part B — Facilitated Emissions
Capital markets activities — bonds/equity issuance. 33% attribution factor (vs 100% for financed). Released 2023.
Part C — Insurance-Associated Emissions
Re/Insurance. Released 2022.
Data quality scores 1–5
- Score 1: Verified actual data
- Score 2: Audited data
- Score 3: Reported but unverified
- Score 4: Sector-average emission factor + revenue
- Score 5: Sector-average proxy (least reliable)
Why it matters in UAE
FAB, Emirates NBD, ADCB, ENBD Asset Management, Mubadala, ADQ — all signatories. CBUAE Climate Risk Principles reference PCAF for financed emissions disclosure (mandatory for banks 2024+).
SBTi — Science Based Targets initiative
What it is: Joint initiative of CDP, UN Global Compact, WRI, WWF. Validates corporate emission targets against the Paris Agreement (1.5°C). Now operating under independent SBTi Services Limited (UK).
Target types
- Near-term (5–10 years) — Scope 1 + 2 absolute reduction; Scope 3 if >40% of total. 42% absolute reduction by 2030 from base year is the 1.5°C-aligned default (~4.2% per year).
- Long-term (Net Zero by 2050) — under the Corporate Net-Zero Standard (v1.2 March 2024; v2.0 in development).
- FLAG (Forest, Land & Agriculture) — sector-specific guidance for land-intensive sectors; mandatory if FLAG >20% of revenue.
Net-Zero Standard requirements
- Both near-term + long-term targets required
- ≥90% absolute emissions reduction by 2050 (Scope 1+2+3)
- Carbon removals only for residual ≤10%
- No use of avoided-emission offsets to count toward target
SBTi paused new oil & gas validations in 2022 pending a fossil-fuel sector standard. ADNOC, TAQA, etc. cannot currently get SBTi-validated targets. If the interviewer says "ADNOC has an SBTi target", they're wrong.
Walkthrough: Building a GHG inventory for a Dubai real-estate developer
This is the most-asked open-ended question. Memorise the 6-step structure.
- Set the organisational boundary — for a developer with JVs across emirates, default to operational control and document it. Disclose in methodology.
- Set the base year — typically the most recent year with complete data. Write a recalculation policy with a 5% significance threshold.
- Define operational boundaries per category:
- Scope 1: gas boilers, gen-sets, refrigerant top-ups
- Scope 2: landlord-controlled electricity + district cooling (Empower/Tabreed)
- Scope 3 material categories: Cat 1 (cement, steel embodied carbon), Cat 2 (capital goods), Cat 11 (energy use of tenants in sold/leased buildings), Cat 13 (downstream leased assets if lessor)
- Collect activity data — utility bills, fuel invoices, refrigerant logs, BoQ for embodied carbon.
- Apply emission factors:
- DEFRA for fuels and refrigerants
- IEA or MOCCAE for UAE grid
- District cooling provider-specific factors (Empower, Tabreed publish these)
- EPDs or ICE database for materials
- Compile, document assumptions, calculate AR6 GWPs, get third-party limited assurance, disclose against GRI 305, ISSB IFRS S2, and the SCA Sustainability Report.
Boundary → Base year → Operational boundaries → Activity data → Emission factors → Compile + assure + disclose.
That's the universal template. Drop in sector-specific examples (O&G has Cat 11 use of sold products dominant; banks have Cat 15 financed emissions dominant; real estate has Cat 1 embodied + Cat 13 downstream leased assets).
Practice Q&A
"Both are required under the GHG Protocol Scope 2 Guidance — 'dual reporting'. Location-based uses the grid average emission factor where the consumption occurs — for the UAE that's around 0.42 tCO2e per MWh, declining as Barakah and the Mohammed bin Rashid Solar Park scale.
Market-based uses contractual instruments — supplier-specific factors, PPAs, I-RECs in our region, or green tariffs like DEWA's Shams. The market-based number is what shifts when you procure renewables.
Importantly, for any market-based claim the instrument must meet the eight Scope 2 Quality Criteria — vintage matched to consumption year, retired only once, within the same market boundary. RECs do not reduce the location-based number."
"Category 15 is investments — what banks, asset managers and insurers usually call financed emissions. The GHG Protocol defers methodology to PCAF, the Partnership for Carbon Accounting Financials.
PCAF Part A covers financed emissions across seven asset classes — listed equity, corporate bonds, business loans, project finance, commercial real estate, mortgages, motor vehicle loans, plus sovereign debt added in 2022.
The attribution principle is the financed entity's emissions multiplied by your share of their financing — outstanding loan over enterprise value including cash for listed companies.
PCAF also has a 1–5 data quality hierarchy from verified actual data to sector-average proxies. Part B added facilitated emissions for capital markets activities at a 33% attribution factor, and Part C covers insurance-associated emissions."
"We recalculate the base year inventory for structural changes — M&A, divestitures, outsourcing — exceeding our 5% significance threshold. Also for methodology changes, updated emission factors, GWP updates like AR5 to AR6, and discovered errors above the threshold.
We do not recalculate for organic growth or production changes within existing operations. The policy is documented in our methodology note and applied consistently. For example, the AR5 to AR6 GWP migration triggered a recalculation that raised methane figures roughly 3% across the inventory."
"You commit to SBTi within 24 months of submitting a target for validation. The minimum bar is a 1.5°C-aligned near-term target — typically 42% absolute reduction in Scope 1+2 by 2030 from a base year no earlier than 2018, which is roughly a 4.2% annual linear reduction.
Scope 3 must be included if it exceeds 40% of total emissions. For long-term net zero, you use the Corporate Net-Zero Standard which requires a near-term plus a long-term target hitting at least 90% absolute reduction by 2050, with the residual 10% addressed by carbon removals — not avoided-emission offsets.
For land-intensive sectors above 20% revenue from FLAG activities, FLAG-specific targets are mandatory. One important nuance for the UAE — SBTi has paused validations for upstream oil & gas pending a fossil-fuel sector standard, so ADNOC and similar producers can't currently get an SBTi-validated target."