Coffee machine and kettle: how they work

In short: Kettle and coffee machine heat water with an electric heating element. The kettle switches off automatically after boiling; the coffee machine pushes the hot water through the ground coffee.

In more detail: A heating element converts electrical energy almost completely into heat.

In detail

• Kettle: A bimetallic switch or steam sensor cuts the power at about 100 degrees.
• Efficiency: Kettles are usually more efficient than hobs.
• Filter coffee machine: A heating element heats the water, which drips via a riser tube into the filter.
• Bean-to-cup machine: Grinder, brewing unit and pump with about 9 bar pressure for espresso.
• Capsule machine: Practical but more waste.
• Descaling: Limescale makes appliances inefficient; descale with citric or acetic acid (waerme-und-temperatur).
• Water temperature: Ideal for coffee is about 92 to 96 degrees.
• Saving energy: Heat only the amount of water needed.