# Does oxy-fuel firing lower a furnace's carbon footprint?

Canonical: https://senseible.earth/answers/oxy-fuel-firing-furnace-co2

It cuts fuel, because burners no longer heat the nitrogen in air. But making oxygen takes electricity. Your Scope 1 falls; your Scope 2 rises if you run an oxygen plant, or Scope 3 rises if you buy liquid oxygen. Count both before calling it a saving.

## What changes

- Fuel per tonne melted falls (Scope 1).
- Oxygen plant electricity is added (Scope 2), or bought oxygen (Scope 3, Category 1).
- Flue gas volume drops, which helps any heat recovery or capture later.

## How to compare

1. Fuel saved per tonne multiplied by its factor.
2. Minus oxygen used per tonne multiplied by the electricity per tonne of oxygen and 0.710 kg CO2 per kWh, or the supplier's figure for bought oxygen.
3. The difference is the net change.

## What Senseible does here

Senseible reads fuel invoices and electricity bills and applies IPCC 2006 factors and the CEA grid factor (0.710 kg CO2 per kWh), so you can compare Scope 1 and 2 before and after a change from the documents themselves.

- [Industrial gases in Scope 3](https://senseible.earth/answers/industrial-gases-oxygen-nitrogen-scope-3)
- [Glass container furnace](https://senseible.earth/answers/glass-container-furnace-emissions-per-tonne)
- [Recuperator air preheat](https://senseible.earth/answers/recuperator-combustion-air-preheat-fuel-saving)

Sources: [2006 IPCC Guidelines, Volume 2 Energy](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html), [GHG Protocol Corporate Standard](https://ghgprotocol.org/corporate-standard), [GHG Protocol Scope 3 Standard](https://ghgprotocol.org/corporate-value-chain-scope-3-standard)

Last reviewed 2026-10-22.