What are the chances of getting a Daily kWh Usage counter added that resets at midnight?
This is easy to do in Emoncms, just log the energy accumulator then use graph with ‘delta’ enabled or to view daily, weekly or monthly data: Calculating Daily kWh - Guide | OpenEnergyMonitor
You can also use an Emoncms app like MyElectric2 e.g
I think getting it backed into OpenEVSE would be much more ideal and then it could be displayed here.
I do think the ability to create a static data store of the accumulated values has benefit.
5 year’s worth of 10s data isn’t very valuable, but that data aggregated into daily & monthly totals, more so for long term trends.
I store weather data and used pywws for many years. The beauty of this was it generated summary totals and stats (max min etc). Sadly my weather station no longer works with this and I have yet to find a good alternative. If Emoncms could generate these summary values, it would be a great addition to the processing capabilities.
It has been mentioned elsewhere about timed processing. Something that could be set to run at specific times or frequency and generate a feed from that. It might not even get logged.
For instance, Energy used in last hour, triggered by a new value (just published to MQTT or dashboard) - I know this is to some extent done in the built-in apps, but not readily available to publish. Energy used yesterday, triggered at midnight. Max & Min temperature in last 24Hrs (updated every 15 min) or Previous day (triggered at midnight) and logged.
Lots of possibilities, that can be done by InfluxDB, but are reasonably complex to setup. A simpler, lightweight solution, just isn’t out there currently that I have found. I suspect, because of the architecture of Emoncms, implementation would be reasonably easy (if you know how!).
What would the use case be for it? Even with my plugin hybrid I very rarely charge more than once a day, so in essence doesn’t the session energy basically give what you want?
I agree, session energy is often more useful since charging session often span two days e.g charging from 8pm - 2pm
My solar system tells me how much I have generated and used each “day”… My house power meter tells me the same…
Our car is plugged in several times a day between errands so I’d like to have a precise “daily” kWh count so I can correlate it with my daily energy use/generation for the rest of the house. A session could cross midnight so isn’t really useful to me.
The session energy will be useful to people too so I’m not proposing getting rid of that… Just adding another metric.
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For me, as I said, 5 years of 10s data is a waste and not easily used. 5 years of daily data is much more useful!
On my dashboard, “How much energy did I use yesterday” (just like a CAD) would be a useful metric.
Maybe not too terribly complex. 
A continuous query makes it fairly easy to downsample data to a user defined interval
Paul Reed uses this one: (Ref: Grafana Dashboard Project - #5 by Paul)
cq_5m
CREATE CONTINUOUS QUERY cq_5m ON emondata
BEGIN SELECT mean(grid) AS grid, mean(solar) AS solar, mean(divert) AS divert, mean(usage) AS usage INTO emondata.one_year.downsampled_iot FROM emondata.one_day.iot GROUP BY time(5m), grid, solar, divert, usage
END
Which I adapted to suit my need and came up with:
cq1
CREATE CONTINUOUS QUERY cq1 ON energy
BEGIN
SELECT mean(*) INTO energy.autogen.AVPV FROM energy.autogen.GENW GROUP BY time(1m)
END
It downsamples 5 second data to 1 minute data.
Yields a graph that appears on-screen very fast
Eight months of data popped up on-screen in well under 0.5 seconds. Viz:
I still feel there is merit to showing a daily kWh usage here in the wifi portal…
@glyn.hudson @jeremypoulter what do you think the chances of getting a daily kWh counter added to the web interface?
There is an issue about when the total energy is updated, will probably have to do it after that so the WiFi module has a live total value, should be fairly easy to add them, but sorry, don’t know when that will be.
Hi @jeremypoulter I’d be very excited if you could get this added at some point. Thanks 