Page 1 of 1
Difference between "Energy Usage" and "Power Usage"
Posted: Friday 06 April 2018 11:57
by Marque1968
Sorry for being such a noob, but I don't see what the difference is between Energy Usage and Power Usage.
This is my current stat:
I only switch on the store lights twice a week. This is shown with the yellow "Power Usage" line. All looks fine to me. These are the times the CoolCam Neo plug is switched on.
But what I don't get is the blue bars that show "Energy Usage". It is not level at all hours, so it does measure something. It just baffles me what it can be.
What is "Energy usage" and how can it show such usage when the plug is off? Does it measure the whole house? I don't think so as today I have a higher Power Usage, then I have Energy Usage.
(PS: for the bug-lovers: After exporting this PNG, the labels are duplicated, and they will duplicate each time you select export)
Re: Difference between "Energy Usage" and "Power Usage"
Posted: Friday 06 April 2018 18:45
by McMelloW
Re: Difference between "Energy Usage" and "Power Usage"
Posted: Friday 06 April 2018 19:09
by jake
Even while you know the difference, it doesn't explain the electricity usage. The graph doesn't tell the switch points, so it is remotely possible that the are many short power spikes that are not shown in the 5 minute intervals.
In general this does look very weird and I am not able to explain the periods where there is no power, but plenty of energy registered.
Re: Difference between "Energy Usage" and "Power Usage"
Posted: Friday 06 April 2018 20:03
by McMelloW
In my case a P1 smart meter and a usb cable connection and receives every 10 sec the meter readings in Domoticz
Re: Difference between "Energy Usage" and "Power Usage"
Posted: Saturday 07 April 2018 21:34
by jake
McMelloW wrote:In my case a P1 smart meter and a usb cable connection and receives every 10 sec the meter readings in Domoticz
Yes, I have the same. I also have some power plugs that register power and energy, but I have never seen the content of a graph like that one in this topic.
Re: Difference between
Posted: Saturday 07 April 2018 22:53
by McMelloW
jake wrote: ↑Saturday 07 April 2018 21:34
McMelloW wrote:In my case a P1 smart meter and a usb cable connection and receives every 10 sec the meter readings in Domoticz
Yes, I have the same. I also have some power plugs that register power and energy, but I have never seen the content of a graph like that one in this topic.
Did not look very carefully to the graph. It is very odd. Looks like the power usage stopped measuring/calculating for a period of time
Re: Difference between "Energy Usage" and "Power Usage"
Posted: Monday 09 April 2018 9:25
by JamesSullivan
It’s common for people to use the words “energy” and “power” interchangeably. Energy is the total amount of work done, and power is how fast you can do it. In other words, power is energy per unit of time. Power is watts. Energy is watt-hours.
Re: Difference between "Energy Usage" and "Power Usage"
Posted: Monday 30 April 2018 15:42
by nixalsschrott
Well, nevertheless it should look more like mine picture attached.
I have realized some problems with correct measurements in certain beta version.
Try to use latest beta, for me there it works.

- Watt vs kW
- CA3AD85F-0B0A-4387-BFE4-7A788CAB3EDB.jpeg (117.77 KiB) Viewed 2339 times
Re: Difference between "Energy Usage" and "Power Usage"
Posted: Monday 30 April 2018 22:05
by Nautilus
I don't know whether it could be related but one of my Fibaro wall plugs suddenly stopped reporting power usage. Funny enough (and similarly to this) it still kept reporting energy usage. After a few restarts it seems to work ok again. Now that I think about it, I've had a few weird issues with my z-wave devices with a recent beta...