# Is induction hardening lower carbon than furnace hardening?

Canonical: https://senseible.earth/answers/induction-hardening-vs-furnace-hardening-co2

Often, for parts that need only a hard surface. Induction heats a thin surface layer with electricity in seconds, while a gas furnace heats the whole part and the furnace. The answer depends on your grid factor (0.710 kg CO2 per kWh) and the gas saved, so compare per part.

## Why induction can win

- Only the surface that needs hardening is heated.
- No furnace to keep hot between batches.
- Short cycle, so little standing loss.

## Where furnaces still fit

- Through-hardening whole parts.
- Case carburising, which needs time at temperature in a controlled atmosphere.

## Compare per part

Induction: kWh per part (from a sub-meter) multiplied by 0.710. Furnace: gas per batch multiplied by 2.05 kg CO2 per scm, divided by parts per batch, plus any endothermic gas used.

## 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.

- [Heat treatment emissions](https://senseible.earth/answers/heat-treatment-emissions-per-tonne)
- [Induction billet heater](https://senseible.earth/answers/induction-billet-heater-vs-oil-fired-forging-furnace)
- [Crankshaft footprint](https://senseible.earth/answers/crankshaft-carbon-footprint-per-piece)

Sources: [2006 IPCC Guidelines, Volume 2 Energy](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html), [CEA CO2 Baseline Database for the Indian Power Sector](https://cea.nic.in/cdm-co2-baseline-database/?lang=en), [GHG Protocol Corporate Standard](https://ghgprotocol.org/corporate-standard)

Last reviewed 2026-10-22.