I subscribe to Octopus Go - a tariff that gives me 4 hours (00:30 - 04:30) of very inexpensive electricity (at the moment 7.5p/kWh). And of course I wanted to get this into my emoncms dashboard/graphs with as little effort as possible.
Basically what I wanted to do is to split data from my main feed to the house into 2 distinct feeds, one for consumption during low price time, and one during high cost time (I already have a feed for the sum of these - the standard main feed monitoring which I would like to keep).
There are lots of methods to do this already - in theory, but all of them are either too complex for me, or does not work).
As an example the TimeOfUse apps will not work for me as they seem to map the data wrongly and give me negative values for total consumption. I’m too lazy to debug these.
But it turns out that Emoncms already have the tools I need built into the combination of “Schedule” and “Input process list” to give me this
(and I hope the image made it through to the topic here - never tried this before)
You should here see the 2 feeds with “cheap tariff” as green colour and “normal tariff” as blue.
Btw. all car charging goes into the “cheap tariff” at night, together with consumption for our hot water tank. I have also split out the car charging data as a separate sub feed in emoncms, but that is for another topic.
Under “Schedule” I have one entry
for “Octopus_low_rate” for the time interval “00:30-04:30”
And the rest happens under “Inputs” - please ignore some of the suboptimal stuff in there - this has evolved organically, not through proper design.
So in other words very simple as soon as I understood the concepts behind inputs and schedules.
Feel free to tear apart and use - or ignore my rambling description.
I publish all the data to MQTT - and use it for simple displays around the house to make us aware of the energy usage in real time.