# Electric heating

Heating with electricity: resistance heaters, induction, electric arc furnaces and microwaves.

Source page: https://www.materialinsights.org/energy/e_electric_heat/

Conversion and use · Conversion devices · No. 105

- Conversion and use
 Conversion and use · Conversion devices · Foundation · Energy

A kettle turns all its electricity into heat, yet a heat pump water heater does the same job on less than half.

Chart: Illustration: Electric heating

##### Where it comes from

Chart: Map of where it comes from

Electricity becomes heat in four ways: pushed through a resistance, induced as swirling currents in metal, struck as an arc, or beamed into food as 2,450 MHz microwaves.

##### Three things to know

1. No resistance heater can beat 100% efficiency, but a heat pump water heater moves outside heat and uses less than half the electricity.
2. Modern arc furnaces need 400 to 500 kWh per tonne of steel, not far above the roughly 370 kWh needed just to melt scrap.
3. A home microwave gets 50% or less of its electricity into the food, though cooking uses only about 71 kWh a year.

##### The journey

1. 1 **Grid power**Alternating current at 50 or 60 Hz
2. 2 **Power shaping**Transformer, inverter or magnetron conditions the current
3. 3 **Heat made**Resistance, eddy currents, arcs or microwaves
4. 4 **Into target**Water, pans, food or a scrap charge
5. 5 **End use**Geysers, hobs, ovens and steel melt shops

##### Go deeper pick a tab to open it in full

## Other sections

- [Overview](https://www.materialinsights.org/energy/e_electric_heat/overview/index.md)
- [Correlation](https://www.materialinsights.org/energy/e_electric_heat/correlation/index.md)
- [Science and limits](https://www.materialinsights.org/energy/e_electric_heat/science/index.md)
- [Value chain](https://www.materialinsights.org/energy/e_electric_heat/valuechain/index.md)
- [Unit economics](https://www.materialinsights.org/energy/e_electric_heat/economics/index.md)
- [Engineering methods](https://www.materialinsights.org/energy/e_electric_heat/methods/index.md)
- [Equipment and suppliers](https://www.materialinsights.org/energy/e_electric_heat/equipment/index.md)
- [Relationships](https://www.materialinsights.org/energy/e_electric_heat/links/index.md)