Let’s take the example for electricity. What is a kWh? Well one kWh is the Energy consumed by an appliance of 1 kW “One kilo Watt” or 1.000 W (one thousand Watt) when is used during 1 hour. Or an appliance of 500 W used during 2 hours. Yes, it is power multiplied by time you use an appliance.
So, when it comes to save on energy, there are two things to watch: first reduce the power of the appliance, less Watts, results in less Energy (Watt hours) consumed. How? Well in the case of light bulbs for example, you could replace an older incandescent light of eg. 100 W by a 10 W LED light that will provide you as much light! You save a ten fold. This works for lighting but also for your older house hold appliances as TV’s, Fridges, etc.
Another important parameter is the time an appliance is used. Like for lights, make use of timers, presence detectors, ambient light sensors to turn lights on only when needed, i.e. someone is in the room and light is needed. Here you have an impact on the quantity of energy used, the “hours” factor.
In order to manage your energy consumption, you’ll need tools. The tool must be able to show you the power of each of your appliances and at the same time, register per appliance, how much time you use it per day, week, month and per year. It will show you the kW x hours or kWh consumed per appliance!
Smappee is one that shows you the consumption per appliance on the Appliance DNA!
The DNA of my Expresso shows I make an average of 6x expresso’s per day, the machine takes 1138 W of power during 28 seconds per shot for a total of 3 minutes and 6 seconds per day. The making of 6 expresso’s consumes 58 Wh or 0,058 kWh per day. At a cost of 0,22 EUR per kWh: 0,01 EUR per day. The Year tab shows similar information: I drink 1365 expresso’s per year and this consumes 15 kWh and cost me 3,69 EUR.