How many CBAM certificates would 10,000 tonnes of steel rails need in 2027?
In the Commission's own example, 3,690. Rails from an integrated blast furnace works carry 1.539 t CO2 direct and 0.028 t indirect per tonne, so 15,670 t CO2. Free allocation for 2027, 0.95 x 1.00 x 1.261 = 1.198 t per tonne, removes 11,980 t, leaving 3,690 before any carbon price paid abroad.
Where 1.539 comes from
- A mass balance of every carbon input and output gives the works' direct emissions: 7,866,044 t CO2.
- Waste gas burnt to make electricity is deducted: 478,959 t, leaving 7,387,085 t.
- Divided over 4,800,000 t of sheets, bars and rails, that is 1.539 t CO2 per tonne.
- One combined process covers sinter, iron, steel and rolling, allowed because none of those precursors is sold.
Why a steel product has indirect emissions
Electricity does not count for steel, but it does for sintered ore. The sinter plant's 241,111 MWh gives 132,797 t CO2, and that carries into the rails as 0.028 t per tonne.
Where 1.261 comes from
- Sinter benchmark 0.086; pig iron 1.089 plus 1.400 t of sinter per tonne gives 1.209.
- Crude steel 0.188 plus 0.800 t of pig iron per tonne gives 1.156.
- Rails 0.057 plus 1.042 t of crude steel per tonne gives 1.261.
- Without actual data, the declarant would use the default benchmark of 1.383 instead.
The guidance's calculation for 10,000 t of rails imported in 2027
- Direct: 10,000 x 1.539 = 15,390 t CO2
- Indirect: 10,000 x 0.028 = 280 t CO2
- Total: 15,670 t CO2
- Free allocation: 0.95 x 1.00 x 1.261 = 1.198 t per tonne, so 10,000 x 1.198 = 11,980 t
- Certificates: 15,670 minus 11,980 = 3,690
The Commission's example values. 0.95 is the CBAM factor for 2027 and 1.00 the correction factor assumed in the guidance. A carbon price actually paid in the country of production can be deducted further.
What Senseible does here
Senseible's CBAM cost calculator applies the free allocation phase-out year by year from 2026 to 2034, so you can see how the cost of a rail order moves over time.
Last reviewed 2026-11-01.