White paper 06 · Chapter 11
Evidence gaps: what is not yet known, and how it will be resolved
Every number for the RC-1 works in this paper is an estimate made before front-end engineering, before supply contracts and before a single heat. That is unavoidable at this stage, and it is why each figure carries a status and a range. This chapter lists the gaps that matter most for the conclusions, explains why each matters and states how and when it will be closed. None of them overturns the central finding, that an electric-arc works on Cameroon’s grid would sit far below route averages, but several could move the illustrative intensity by a tenth of a tonne or more.
In this chapter (5)
11.1 Gaps that could move the footprint
The largest uncertainties concern the inputs that the works buys rather than the processes it runs: the carbon content of imported iron units, the share of scrap it can secure and the emission factor of the electricity it draws. The tornado analysis in Chapter 4 ranks them; the table below sets out how each will be resolved.
Table 11.1 Evidence gaps affecting the carbon footprint
| # | Gap | Why it matters | How it will be resolved | When |
|---|---|---|---|---|
| 1 | Carbon intensity of the DRI/HBI actually bought (0.5 to 0.9 t/t assumed) | Largest single block of the footprint; ±0.07 t per tonne of product | Supplier-specific, verified data for every cargo; purchasing specification with an intensity ceiling | Phase 1 procurement |
| 2 | Achievable scrap share, domestic and imported | ±0.09 t per tonne for each 10 points of charge | Scrap market survey in Cameroon and the region; import supply contracts; quality tests | Before Phase 1 investment decision |
| 3 | Grid emission factor for 2025 onwards; the harmonised combined-margin factor used by lenders; seasonal variation | ±0.1 t per tonne for each 100 g/kWh | Published Ember data; the IFI harmonised dataset; hourly or monthly utility data; terms of the supply contract | Ongoing; at contract signature |
| 4 | Furnace direct emissions, minor fuels and switchgear SF6, and furnace energy use (0.10 t/t and 450 kWh/t planning values; up to about 490 kWh/t with 30% DRI) | Largest uncertainty in direct emissions; the minor sources decide on which side of the EP4 threshold Phase 1 falls | Technology supplier’s guaranteed consumptions at front-end engineering; measured carbon balance after commissioning | Front-end engineering; first year of operation |
| 5 | Other purchased inputs (ferroalloys, lime, electrodes, refractories) and freight | Needed for a complete product footprint and EPD | Life-cycle inventory at front-end engineering; supplier data | Before first EPD |
| 6 | Construction emissions and land-use change on the site | Not yet quantified | Vegetation and carbon-stock survey in the environmental and social impact assessment; construction plan | Impact assessment |
Source: Cameroon Steel; sensitivities from the WP06 model (Chapter 4).
11.2 Gaps that affect carbon border exposure and certification
Table 11.2 Evidence gaps affecting market and certification outcomes
| # | Gap | Why it matters | How it will be resolved | When |
|---|---|---|---|---|
| 7 | CBAM benchmark values for long products and their route classification for RC-1’s charge | Sets the free-allocation adjustment for EU-bound tonnes | Review of the annexes to the CBAM implementing regulations; legal advice | Before any EU sale |
| 8 | CBAM default values that would apply to Cameroonian products | Determines the cost of unverified data for buyers | Review of the default-value annex by CN code | Before any EU sale |
| 9 | Numeric thresholds of the Steel Climate Standard and LESS classes; design of the EU low-carbon steel label | Certification targets and buyer requirements | Monitoring of standard-setters’ publications | Ongoing |
| 10 | Existence of an electricity attribute-certificate registry in Cameroon | Credibility of any market-based Scope 2 claim | Engagement with the regulator and the utility | Before a market-based claim |
Source: Cameroon Steel.
11.3 Gaps that affect the green-iron option
Table 11.3 Evidence gaps for the reserve direct-reduction module
| # | Gap | Why it matters | How it will be resolved | When |
|---|---|---|---|---|
| 11 | Whether Cameroonian ore can be upgraded economically to DR-grade concentrate and pellets | Decides whether a domestic module would use local or imported feed | Metallurgical testwork, concentrate and pelletising study with the sister mining company | Studies from 2027 |
| 12 | Gas reserves and supply terms for a direct-reduction module | A module needs about 9 to 10 PJ a year per Mt of DRI | Reserve audit; negotiation with gas producers | Before any module decision |
| 13 | Cost and firmness of low-carbon electricity for hydrogen | Hydrogen-based iron needs power at about US$35 to US$40/MWh to compete on published estimates | Power supply studies; new hydro or firming options | Long term |
| 14 | Port bulk handling for pellets and HBI | Required for imports of pellets or exports of HBI | Engagement with the port and the mineral terminal | With the module decision |
Source: Cameroon Steel; requirements from Chapter 6.
11.4 Gaps that affect adaptation design
Table 11.4 Evidence gaps for climate adaptation
| # | Gap | Why it matters | How it will be resolved | When |
|---|---|---|---|---|
| 15 | Short-duration rainfall intensities (intensity-duration-frequency curves) for Kribi | Sizing of roof drainage, channels and retention | National meteorological service data; site station from the start of construction | Design |
| 16 | Site heat-stress statistics (wet-bulb globe temperature) | Heat-stress plan; equipment ratings | Site measurements; reanalysis calibrated to the station | Design and first year |
| 17 | Lightning flash density | Lightning protection design | Satellite lightning climatology; site records | Design |
| 18 | Kribi-specific sea-level projections | Design of any coastal infrastructure | IPCC AR6 regional projections tool | Before any coastal works |
| 19 | Slag leaching behaviour and local acceptance for road use | Outlet for about 45,000 t a year in Phase 1 | Standard leaching and stability tests; road-authority approval | Before commissioning |
| 20 | Access to a licensed EAF dust recycler and export permits | Avoiding a hazardous-waste liability | Recycler contract; Basel Convention procedure | Before commissioning |
Source: Cameroon Steel.
11.5 How the gaps will be closed and reported
The gaps fall into three groups. The first, supplier, contract and study data (gaps 1, 2, 4, 5, 7, 8, 11, 12, 13 and 20), closes as the project moves through front-end engineering, procurement and the ore and gas studies; each new data point will replace a planning value in the RC-1 reference configuration, with its source and date. The second, site and environmental data (gaps 6, 15, 16, 17 and 19), closes through the environmental and social impact assessment and the site weather station. The third, external developments (gaps 3, 9, 10, 14 and 18), closes as institutions, the port and the grid publish or build; Cameroon Steel will update its figures when they do. Each of the twenty gaps sits in exactly one group.
The annexes that follow set out the method and assumptions in full (Annex A), define the technical terms used (Annex B), list every source (Annex C) and print the values behind every figure (Annex D).
Cite this chapter
Cameroon Steel (2026). Lower-carbon steel from Cameroon: it could reach a third of the world’s carbon intensity. White paper 06, chapter 11: Evidence gaps: what is not yet known, and how it will be resolved. CS-WP-06. https://www.cameroon-steel.com/en/library/lower-carbon-steel/evidence-gaps/
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