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Methodology

How Open Assets calculates plant-level emissions using the Asset-based Planning Approach.

What is APA?

APA (Asset-based Planning Approach) is David Kampmann's methodology from his 2024 paper for calculating company-level emissions projections based on physical asset data.

Instead of relying on corporate targets or intensity benchmarks, APA models emissions from the bottom up using actual plant-level data: which plants exist, what technology they use, where they are located, and how much they produce.

Core Calculation

Plant Emissions = Allocated Production × Emission Factor

= (Plant Capacity / Total Company Capacity) × Company Production × EF(country, technology, year)

Company Emissions = Sum of all plant emissions under that ownership

The utilisation rate distributes reported production across plants proportionally to their capacity share.

Steel APA Implementation

Data Source: GEM GIST December 2025

Three standalone Excel files from the Global Energy Monitor's Global Iron and Steel Tracker, covering 800+ plant-status entries:

  • Plant-level data — plant_id, country, parent, owner, status, start_year
  • Iron unit data — BF and DRI unit capacities (technology, capacity_ttpa)
  • Steel unit data — BOF and EAF unit capacities (technology, capacity_ttpa)

26 Companies Tracked

The original 14 companies from Kampmann's paper plus 12 expanded companies, resulting in 229 company-year APA pairs covering 2014–2024.

Emission Factors

Based on Koolen & Vidovic (2022) JRC129297 — country-specific emission factors for the steel industry and its trading partners.

BF-BOF (Scope 1 + Upstream)

Country-specific, time-varying with 0.5%/year compound improvement from 2020 reference:

EF(country, year) = EF_base(country) × (1 - 0.005)^(year - 2020)
Region Base EF (2020) 2014 EF 2024 EF
EU 1.770 1.824 1.735
China 1.760 1.814 1.725
India 3.720 3.834 3.646
Japan 2.050 2.113 2.009
United States 1.940 1.999 1.902
Brazil 2.190 2.257 2.147
South Korea 2.000 2.061 1.960
Russia 2.790 2.875 2.735
Global (fallback) 2.314 2.385 2.268

Rationale: Worldsteel Sustainability Indicators show global BF-BOF intensity is largely flat over 2014-2024 (<5% total change). IEA assumes 0.3-0.7% annual improvement. We use 0.5% as a middle estimate.

EAF (Scope 1 only) — Static

EAF scope 1 emissions are very small (0.02-0.12 tCO2/t) and kept constant across all years.

DRI — Static (technology-specific)

Coal-based DRI: 3.10 tCO2/t (India, China, South Africa). Gas-based DRI: 1.05 tCO2/t (all others). Hydrogen DRI: 0.04 tCO2/t (future technology).

Production Data Hierarchy

Five sources, prioritised (lower number = higher priority):

Priority Source Coverage
0 Kampmann BAU (reported) 14 companies, 2020-2023
1 Annual report extraction Varies by company
2 Curated reports CSV 26 companies, 2014-2024
3 Kampmann ALD data 14 companies, 2020-2023
4 GEM plant production Variable (50% coverage floor)

Year-Specific Plant Filtering

Plants are filtered per year based on GEM status and start_year, meaning the plant set changes over time. New plants come online and the technology mix shifts — this is the first-order effect on weighted emission factors.

Status Rule
Operating / Pre-retirement Include if start_year ≤ year
Construction Include if start_year ≤ year (came online)
Retired / Mothballed Include for all historical years
Announced / Cancelled Always exclude

What APA Is Not

NOT TPI intensity benchmarks (those are sector-wide, not asset-level)
NOT corporate target tracking (that’s NZT — useful for comparison only)
NOT satellite emissions estimates (that’s ClimateTrace — useful for validation)
NOT scenario pathway alignment (that’s the PCP/SDA/ACA analysis that uses APA as input)

APA is purely: Assets → Emission Factors → Baseline Emissions, driven by physical plant data and reported production.