tracking down high electricity usage

nxdmsandkaskdjaqd

victor2 said:

nxdmsandkaskdjaqd said:

victor2 said:

nxdmsandkaskdjaqd said:

I carried out a review of my idle power consumption overnight.  The lowest standby/idle power I have recorded on my IHD and Home automation is 53 Watts.

STANDBY - 11pm to 7am
Alarm	15
BT Router	10
Ipad on charge	6
Gates	6
Router Amplifier	5.6
Light kitchen	4.7
Ariel Amp	4.4
Light hall	3.5
Digibox	3.33
Internal Camera	2
Garrage Door	2
Picture Frame	1.85
Bedroom Radio	1.65
Wine Cooler	1
Outside Freezer	1
MP3	0.8
Nest	0.8
Phone	0.7
Inside Fridge Freezer	0.2
Mac Book Pro	0
Weather Station	0
Security Sensor
Mirror Downstairs bathroom
Mirror Main bathroom
Mirror Toilet

That is really not very representative, for example two freezers taking a total of 1.2W. When their compressors cut in, it will be much higher. Conversely, the iPad will not be drawing 6W constantly when charging, it will drop to close to zero.
A better way to look at "idle" power use is to take the average overnight kWh taken over several days.

The ipad is on charge all night, and does take 6 watts for most of the night.  The purpose of the exercise was to find the standby/idle watts of the house.  Hence when the compressors on the freezers are not running their standby/idle wattage is 1.3 watts.  Since doing the tests I have shut down a number of the items to reduce the power consumption.

In addition, my overnight power consumption, with freezers running, is 0.8 KWh in the winter and in the summer 1.1 KWh.

So the lowest column on your graph is between 3am and 4am, where your used just over 0.1kWh, which is equivalent to a constant load of 100W for the hour. Still a good tool for looking at your overall consumption though.

Fridges and freezers are not normally idle for the whole night, so a snapshot at any one moment is not really useful. 

Hardly a power monster, but if your iPad charger is drawing a steady 6W for most of the night, it might be time to look for a new iPad!

The lowest point is just the coincidence of when the freezers are on or not.  The ipad battery is 9.720 mAh so charing at 6w does take most of the night. 

nxdmsandkaskdjaqd

Following on from the above here is the ipad charge overnight.  Not a great image but show the point.

victor2

nxdmsandkaskdjaqd said:

Following on from the above here is the ipad charge overnight.  Not a great image but show the point.

Thanks for that. Made me look closer at an old iPad I have. It has a 7340mAh battery.

Charging from 19% to 100% took 3 hours. The charger started at 11W and gradually dropped to 2.2W as it reached 100%. Used 0.025kWh, so an average of 8W while charging but interestingly remained at 2.2W after it was fully charged (iPad was in standby, but it powers up anyway when you attach the charger).