I hope this will help you save some energy and also a few quid! All calculations are based on a unit price of 35 pence per kWh. If you know the power consumption of an appliance, then the following formula will let you calculate the approximate average hourly running cost.
unit price in pence divided by 1000 multiplied by the number of Watts equals approx cost per hour in pence
pkWh/1000xW = phr
EG for an appliance with a power rating of 200W and your unit rate is 33p per kWh. 33/1000 x 200 = 6.6p per hour
I have calculated the results below from my own appliances in real time. Some things like fridges, freezers, ovens, washing machines etc that cut in and out are difficult to calculate. But the plug in energy monitors are very good. I used a combination of plug in energy monitors and my workshop test equipment to monitor the power consumption.
Some interesting results were that USB phone chargers use no energy when left plugged and not used, well no measurable power. I will test in a different way when I have time, to check how low the power consumption is! I tested Apple, Amazon, Sony, Bose and cheap unbranded ones.
Another interesting result was our chest freezer. It needed defrosting, so I checked this before and after defrosting. There was no change in the power consumption!
The equipment I used for power monitoring.
