Digital power meter

Power consumption @home

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At my employer, an IT business, we are quite aware of energy consumption. Now, I wanted to know how much energy my home office, and other home appliances, do use. Here’s some of the results.

Beforehand, I need to note that electrical power is measured in watts [w], and electrical energy (or work) is measured in watt-seconds [ws] (or more often kilo watt-hours [kWh]). Thus, energy is the amount of power consumed for a certain period of time. That is, what you actually pay for, the amount of energy.

Currently, where I live, the price for one kWh is about 30 Swiss cents. For perspective, when drawing one watt continuously over the course of one year, this costs about 2 Swiss francs.

Home office

I use a quite simple setup with an older Lenovo ThinkPad X1 Yoga (1st gen) laptop (with Ubuntu Linux), and 2 externals monitors, connected via docking station.

home office setupMy home office setup.

This home office setup uses around 63 watts, continuously, when using the internet with a video or remote desktop stream. Interestingly having the screens with bright content, as opposed to dark content, makes a difference of a few watts. So an 8-hour day in the home office costs about 15 Swiss cents.

To connect to the internet, I use, a FRITZ!Box 6842 LTE mobile router. This router consumes around 4 watts, continuously. This is remarkably low.

Household devices

  • The freezer, at -18°C, uses 42 watts, on average. That’s about CHF 5.- per month.
  • My quite old USB charger, on standy (no device connected), actually uses 0 watts. I can keep it connected all the time to the socket outlet.
  • The cheap 10 meter LED strip uses about 17.4 watts, having fully red light. Interestingly, having a green or blue color only uses about 9.5 watts. When turned off (actually in standby with the remote contol unit), it uses virtually no energy.
  • During brewing, the coffee machine uses around 1400 watts, however, actually pouring a single coffee uses about 0.014 kWh. That’s a less than half a cent per coffee.