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--- efficiency_now:building_service:heat_dissipation [2022/10/25 15:13] – yaling.hsiao@passiv.de
+++ efficiency_now:building_service:heat_dissipation [2022/10/26 16:12] (current) – wfeist
@@ Line 1: / Line 1: @@
 ====== Heat dissipation from electrical devices ======
-Electrical energy which is supplied to a device (whether a washing machine, desk lamp, mobile phone charger or television) is not lost but is instead converted by the device into another form of energy. In the case of a light bulb this is in (small) part actually light; otherwise it is almost exclusively heat. Only sometimes is this heat actually "used" (e.g. in the case of a water heater). Other than that, it is almost always only an unnecessary heat flow; in the summer it is a heat loss which may need to be removed by cooling, in winter it is uncontrolled and expensive (30 cents/kWh) additional heating.
+Electrical energy which is supplied to a device (whether a washing machine, desk lamp, mobile phone charger or television) is not lost but is instead converted by the device into another form of energy. In the case of a light bulb this is in (small) part actually light; otherwise it is almost exclusively heat. Only sometimes is this heat actually "used" (e.g. in the case of a water heater). Other than that, it is almost always only an unnecessary heat flow; in the summer it is a heat loss which may need to be removed by cooling, in winter it is uncontrolled and expensive (15-30 cents/kWh if not subsidized) additional heating.
 Devices that produce a lot of heat (and exactly that is not their main purpose) are basically just inefficient.
 First of all it is necessary to identify such energy consumers. There are three ways to do that:
   * Checking electricity consumption: inexpensive devices are available for measuring electricity consumption; they do not always have to be purchased: they can also be loaned from many energy consultants and some local electricity providers. More exact information on how such a measurement can be carried out is provided in this section.
-  * Feeling with the hand: devices that become quite hot on large surfaces are electricity guzzlers and it is worth checking their electricity consumption. However, also devices that are warm to the touch draw quite a few watts of energy and when these are continuously in operation (5 W are around 44 kWh in a year or electricity costs of more than 13 €) they incur costs and cause unnecessary environmental damage.
+  * Feeling with the hand: devices that become quite hot on large surfaces are electricity guzzlers and it is worth checking their electricity consumption. However, also devices that are warm to the touch draw quite a few watts of energy and when these are continuously in operation (5 W are around 44 kWh in a year or electricity costs of quite some $$) they incur costs and cause unnecessary environmental damage.
   * It is a lot of fun to search for heat leakage using an infrared thermographic camera: scanning of the room takes less than a minute and it is often surprising what one can 'detect' in this way.