GHG Accounting & Carbon Boundary Mapping

1. Why accounting comes before strategy

Lessons 1 and 2 gave you a policy chain and a claim filter. Now you can put those skills to work on the foundation of credible carbon management: deciding what counts.

Accordingly, a carbon strategy becomes decision-ready only when it has a clear boundary. Boards, banks and EU buyers ask for numbers that survive audit. The GHG Protocol Corporate Accounting and Reporting Standard (WRI/WBCSD) remains the global vocabulary for corporate inventories. It separates organisational boundaries (which entities and assets count) from operational boundaries (which sources are Scope 1, 2 or 3). Companies shall account for and report Scope 1 and Scope 2 at minimum; Scope 3 completes the value-chain picture when material. Please watch the WRI GHG Protocol below.

The GHG Protocol source below provides the accompanying standards context.

Meanwhile, for Turkish manufacturers, the pressure arrives from two directions at once. Domestically, MRV and Climate Law raise the cost of weak installation data. Externally, CBAM and buyer questionnaires ask for product and installation stories — not a single comforting plant average. Accounting is how you stop those asks from becoming crises.

Think of the boundary as a contract with three audiences. The board needs a number that explains capital priorities. The verifier needs a number that matches an approved monitoring plan. The buyer needs a number that can travel into a product declaration. Those audiences share arithmetic, but not the same template. You should start by asking which decision and reporting route each data field must serve; this will help you spend the year improving measurement rather than repeatedly translating an inherited spreadsheet.

2. Organisational boundary

Two common consolidation approaches appear in the Corporate Standard:

• Equity share — include emissions according to ownership share.
• Operational control — include 100% of emissions from operations you control.

In practice, you should choose one approach and apply it consistently. You should document leased assets, joint ventures and subcontracted sites explicitly, because auditors and buyers are likely to ask. Otherwise, if a finishing or machining partner is missing from the product story, both your internal hotspot analysis and external CBAM-style response will be weaker. So, we can say that the boundary choice is not abstract philosophy—it is a written rule you can explain and defend. If two directors disagree, you should use the inventory memo to resolve the point before the questionnaire arrives.

Patchell (2018) shows why the organisational memo is useful rather than merely bureaucratic: Scope 3’s full value-chain ambition collides with transaction costs, power asymmetries and responsibility allocation. A clear statement of which entities sit inside your organisational boundary gives you a firm starting point for managing those constraints. Canal Vieira, Longo and Mura (2024) find that even European manufacturing “climate leaders” struggle with value-chain visibility; starting with a clean organisational rule is one practical step a mid-sized Turkish plant can take without waiting for perfect supplier portals.

3. Scope 1 — direct emissions

Scope 1 covers emissions from sources you own or control: stationary combustion (boilers, furnaces), mobile combustion (owned fleet), process emissions (for example calcination), and fugitives (refrigerants, SF₆). The workhorse calculation is activity data × emission factor (× oxidation factor where required) — the same logic Türkiye’s monitoring regulation uses for covered activities.

The following WRI explainer video shows how the Protocol defines and categorises emissions — you can use it when you classify fuel, electricity and subcontracted processes for your boundary.

Likewise, Türkiye’s installation-level monitoring practice treats this arithmetic as infrastructure: approved monitoring plan, activity data, factors, verification. That is why Climate Law penalties for late or missing verified reports bite — the number is meant to travel into an ETS pathway, not decorate an ESG appendix. For exporters, the same Scope 1 ledger often feeds both the legal installation file and the product declaration. You should treat fuel meters as dual-use assets: they answer the verifier and they answer the buyer.

A useful habit from Lesson 2 travels here: you should check whether a single “plant tCO₂e” is masking process emissions that sit in a different annex or physical unit. If calcination or process CO₂ is material for your sector, you should give it its own line and owner so you can explain it confidently to a buyer or verifier.

4. Scope 2 — purchased energy (two numbers)

Scope 2 is indirect emissions from purchased electricity, steam, heat and cooling. The Scope 2 Guidance requires dual reporting where market-based instruments are used:

• Location-based — grid-average factors for the region of consumption.
• Market-based — contractual instruments (for example guarantees of origin) that meet quality criteria.

Buyers may ask for both. Presenting the two figures together helps you avoid implying that a market-based instrument made the physical grid impact disappear. Miller et al. (2022) add a further caution: annual-average grid factors can bias inventories because carbon intensity varies by hour and season—in some U.S. settings by as much as ~35%, while monthly averages rarely fix the problem. For plants with flexible loads or strong “green power” claims, time-matched accounting can change the story. This does not mean every SME needs an hourly model in month one. It means you should understand whether your largest electricity loads coincide with cleaner or dirtier hours, and whether your certificate claim remains credible under that check.

That said, Diniz et al. (2021) sharpen the certificate caution from a different angle: Scope 2 verification is often slow, and traditional renewable-energy certificates can distort who appears to “consume” renewable electricity versus who buys certificates. Their design-science work on Brazil’s GHG Protocol Programme also notes that not every actor wants greater supply-chain transparency. For a Turkish exporter, the board translation is practical: a green certificate that cannot answer a buyer’s dual-reporting request is only one input—not a finished Scope 2 inventory.

5. Scope 3 — material value-chain emissions

Scope 3 includes fifteen categories — purchased goods, upstream and downstream transport, waste, business travel, use of sold products, and more. You will not measure all categories to equal precision in year one. You should focus on material categories: those that dominate the footprint or that a named buyer or regulator requests in writing.

Huang, Weber and Matthews (2009) showed why materiality is essential: on average more than 75% of an industry sector’s carbon footprint sits in Scope 3 sources. Their EIO-LCA categorisation for U.S. sectors also showed that a sector’s top-10 upstream suppliers often capture a large share of that upstream footprint—a practical hint for Turkish plants that cannot audit every tier-3 vendor in month one. You should start with the suppliers and processes that materially move the total. Sector context matters: commuting and air travel can be 7–30% of the analysed footprint for services, but typically under 1% for manufacturing, so adapt the template to your foundry, textile mill or components plant.

By contrast, textile, metals and casting SMEs know the pattern: subcontracted dyeing, machining or finishing can dominate product emissions while remaining invisible in a Scope 1–2-only inventory. You should draw the product story first; then map which Scope 3 categories capture it. A company-wide Scope 1–2 total that ignores that partner is not conservative — it is incomplete.

Materiality here is practical, not decorative. You should ask three questions: (1) which purchased processes sit on the critical path of the SKU the buyer named; (2) which categories would change a board decision if they moved by twenty percent; (3) which data you can improve in ninety days without waiting for a perfect life-cycle model. Those answers usually beat a fifteen-category spreadsheet that nobody owns.

Borchardt et al. (2025), reviewing sustainable supply-chain research on Scope 3, find the literature still concentrates on assessing and estimating more than on managing reductions across the chain—and that many firms’ ESG reports leave Scope 3 incomplete even when those emissions dominate (examples in the review include consumer and food brands where Scope 3 can exceed three-quarters of the total). Stakeholder engagement often reaches only one or two tiers. Estimation is a starting point, but it becomes management only when it changes supplier engagement, specifications or investment. Di Vaio et al. (2025), on shipping Scope 3 disclosure, similarly warn that reporting metrics and “accountable efficiency” are not the same object: disclosure can look complete while management remains thin.

6. Why Scope 3 is growing — Hertwich & Wood (2018)

Is Scope 3 a boutique reporting fashion, or a structural feature of industrial systems? Against this backdrop, Hertwich and Wood (2018) answer with an economy-wide input–output investigation of indirect CO₂ for IPCC sector groups between 1995 and 2015.

Their headline magnitudes:

• global Scope 1, 2 and 3 emissions grew by 47%, 78% and 84%, reaching 32, 10 and 45 Pg CO₂ respectively;
• the industry sector was most important for indirect emissions — Scope 2 of about 5 Pg and Scope 3 of about 32 Pg;
• for buildings, Scope 3 emissions of about 7 Pg were roughly twice direct emissions;
• energy supply and transport stood in contrast, with direct emissions still accounting for more than 70% of total emissions responsibility;
• most of the growth happened in developing countries (see Figure 2).

In line with this, for a Turkish exporter, the board translation is clear: if your buyer asks for product intensity while your spreadsheet only shows a plant average, your reporting structure has not yet caught up with the industrial structure described in the evidence.

Hertwich and Wood also remind policymakers — and plant managers who brief them — that counting Scope 2 and 3 is an accounting for emission-reduction opportunities, not a claim that the same tonne should be taxed twice in every ledger. Your Scope 3 is someone else’s Scope 1. Shared responsibility is the point: the finishing partner, the electricity supplier and the casting house all sit on the same mitigation map. Pretending otherwise produces tidy Scope 1 charts and messy buyer relationships.

7. Three lenses: Protocol, Türkiye MRV, CBAM

The table below summarises which frame typically fits which need — you should keep it beside Figure 3 when you brief a board that confuses the three asks.

Meanwhile, Türkiye has operated installation-level monitoring for Annex-1 style activities since the mid-2010s: approved monitoring plan, monitoring, accredited verification, annual report. Verified emission reports are the data backbone for the emerging national ETS; Climate Change Directorate verification assignments for hundreds of facilities underline that the numbers are treated as infrastructure, not theatre. Climate Law No. 7552 (2025) raises administrative stakes for late or missing verified reports.

Chamber and press reporting — including Ankara Chamber of Industry via Anadolu Agency — stress the trade side in plain language: firms that cannot supply verifiable emission information risk EU market access. Excellence at monitoring for a covered installation does not automatically satisfy a buyer’s Scope 3 questionnaire — or the reverse. Your boundary map should show both lenses.

Here we can bring in some evidence from the field. Below: the first item sits on the boundary between installation MRV, corporate disclosure and buyer-facing product data; the second is the Commission’s official CBAM guidance reference; and finally, the third shows how corporate GHG accounting and climate disclosures have evolved — so you can place your inventory beside what buyers and registries now expect.

A fourth caution travels with carbon trading MRV. Thornbush and Govind (2025) review MRV protocols used in carbon trading (including dryland/nature settings in the Global South). Their point for manufacturers is architectural: trading-project MRV, corporate Protocol inventories and legal installation MRV are related crafts with different templates. You should not paste a voluntary-project monitoring story into an ETS installation file — or into a CBAM product declaration — and call it done.

Accordingly, trade policy makes the product lens sharper still. Reeve and Aisbett (2022) argue that robust public emissions-accounting systems (national accounts and consistent embedded-emissions methods) are a foundation for border carbon adjustments, linked ETS and certification schemes — both for climate efficacy and for WTO-facing consistency. That is why buyer questionnaires feel like “regulation early”: embedded-emissions accounting is becoming infrastructure for trade instruments, not a CSR hobby.

8. The company-average trap and a 90-day plan

In practice, a single plant tCO₂e can hide batch variation, subcontracted processes and site differences. Export-facing manufacturers learn this the hard way when two SKUs share a building but not a process mix: one batch is mostly in-house melting; another routes through purchased machining and different logistics. A plant average then becomes a political number — useful for a press release, useless for a product declaration.

Huang et al. (2009) and Hertwich and Wood (2018) make the arithmetic case against averages that erase the chain: if most of the footprint sits upstream or in Scope 3, a company-wide Scope 1–2 average is not a conservative proxy — it is a different object. Miller et al. (2022) add that even Scope 2 “averages” can mislead when grid intensity varies by hour. The company-average trap is therefore not one error but three stacked: wrong organisational story, wrong Scope mix, wrong temporal resolution.

When you map hotspots:

1. You should list processes in the product’s bill of materials and logistics path.
2. You can mark which are in-house (likely Scope 1–2) versus purchased (Scope 3).
3. You should note where you have meter-quality activity data versus spend-based estimates.
4. You should choose one 90-day measurement priority — usually the largest uncertain hotspot.
5. You should name an owner and a buyer-facing deliverable (for example: product intensity for two SKUs with a documented finishing partner; see Figure 4).

Canal Vieira et al. (2024) show that even “climate leaders” often lack primary supplier data; you can use your 90-day plan to improve one primary data stream rather than implying that all fifteen categories are already mature. You should watch the CBAM explainer video below to connect that work to product-data expectations.

9. Bridge to Lesson 4 — markets need numbers you can defend

Meanwhile, Lesson 4 turns to carbon markets and offset integrity. Markets, offsetting rules and credit sales decks all assume you already know what your own emissions are. Without a boundary, an offset describes someone else’s project without clarifying your plant’s own footprint. With a boundary, you can ask the questions that matter: what is being reduced, relative to what baseline, and does any of it substitute for measured abatement or CBAM product data?

The same discipline helps you recognise Lesson 2’s myths in operational clothing. “Defaults are enough,” “a plant average is fine,” and “Scope 3 can wait” are not abstract errors—they are inventory choices. Hertwich and Wood show that indirect emissions grew faster than direct ones for two decades. Your ninety-day plan will not fix the global structure, but it can help your firm respond to that structure with better evidence.

Until then, you should keep the discipline: write the organisational choice; classify Scopes; separate Protocol, monitoring and product lenses; refuse the company-average trap. Numbers that survive those steps can travel to a board, a verifier and a buyer. Numbers that skip them will not.

References

Anadolu Agency. (2025). Reporting on industry CBAM data readiness (Ankara Chamber of Industry).

Ankara Chamber of Industry. (n.d.). CBAM firm guide.

Borchardt, M., et al. (2025). Are sustainable supply chains managing Scope 3 emissions? A systematic literature review. Sustainability, 17, 6066.

Canal Vieira, L., Longo, M., & Mura, M. (2024). Impact pathways: the hidden challenges of Scope 3 emissions measurement and management. International Journal of Operations & Production Management.

Di Vaio, A., Van Engelenhoven, E., Raimo, N., & Garofalo, A. (2025). Strategic carbon disclosure and accountable efficiency: reporting shipping industry Scope 3 emissions. Business Strategy and the Environment.

Diniz, E. H., et al. (2021). Greening inventories: Blockchain to improve the GHG Protocol Program in scope 2. Journal of Cleaner Production.

GHG Protocol. (n.d.). Corporate Accounting and Reporting Standard; Scope 2 Guidance; Corporate Value Chain (Scope 3) Standard. World Resources Institute / WBCSD. https://ghgprotocol.org

Hertwich, E. G., & Wood, R. (2018). The growing importance of scope 3 greenhouse gas emissions from industry. Environmental Research Letters, 13, 104013. https://doi.org/10.1088/1748-9326/aae19a

Huang, Y. A., Weber, C. L., & Matthews, H. S. (2009). Categorization of Scope 3 emissions for streamlined enterprise carbon footprinting. Environmental Science & Technology, 43(22), 8509–8515.

Directorate of Climate Change (Türkiye). (2025). Verification work assignment / monitoring cycle notices.

Miller, G. J., Novan, K., & Jenn, A. (2022). Hourly accounting of carbon emissions from electricity consumption. Environmental Research Letters, 17, 044073.

Patchell, J. (2018). Can the implications of the GHG Protocol’s Scope 3 standard be realized? Journal of Cleaner Production, 185, 941–958.

Reeve, A., & Aisbett, E. (2022). National accounting systems as a foundation for embedded emissions accounting in trade-related climate policies. Journal of Cleaner Production, 371, 133678.

Ministry of Trade (Türkiye). (n.d.). CBAM overview pages.

Thornbush, M., & Govind, A. (2025). Monitoring, reporting, and verification (MRV) protocols used in carbon trading applied to dryland nations in the Global South for climate change mitigation. Sustainability, 17, 11001.