How much CO2 does a tonne of steel emit?

Answer

BF-BOF (integrated): ≈1.8–2.2 t CO2/t. Scrap-based EAF: ≈0.4 t/t direct (grid-dependent for indirect). The gap is the route, not operator skill — which is why scrap availability is strategic.

From our guide: Decarbonizing Steel — full context, charts and sources there.

Calculate your carbon bill →Read the full guide

People also ask

Why does ammonia emit so much CO2?

What is the cheapest way for a steel mill to cut emissions today?

What intensity KPI does steel report?

What efficiency saving can a steel site book in its report?

What does it cost per tonne of CO2 abated?

How this page is built: heat-loss figures follow ASTM C680 / ISO 12241 (the method behind our public calculators); facility emissions from Climate TRACE & EU ETS verified data across 30,000+ industrial sites; the 2026–2034 schedule is Regulation (EU) 2023/956, not a forecast. Published by Inzonex — manufacturer of modular removable insulation (UK Patent GB2508992.1). Spotted an error? Tell us — we correct on evidence.

Inzonex removable modular insulation on industrial equipment

Cut the tonnes at the source

Hot industrial equipment? Cut the heat loss.

Boilers, kilns, heat exchangers, valves and steam lines lose energy continuously. Inzonex makes patented (UK GB2508992.1) removable modular insulation — snap-fastened covers engineered per temperature tier, not generic off-the-shelf jackets:

Up to 90% less heat loss from insulated surfaces
Surface temperature ≤45 °C — touch-safe for workers (EN ISO 13732-1)
6× faster maintenance access than fixed cut-and-weld lagging — unclips and refits in minutes, no destruction
Inspectable — comes off to check for corrosion under insulation, then refits like-new (generic jackets often don't survive removal)
Typical payback under 2 years (some 9–11 months)

See Inzonex process-equipment insulation →Run the savings study

Source: Inzonex Carbon Hub — inzonex.co.uk/carbon · prices dated as shown on each figure · schedule per Regulation (EU) 2023/956 · indicative analytics, not compliance advice.