Chart aggregation per 15minutes

I use the charts to display lots of things eg my energy consumption. I now have hourly/monthly/yearly views, but I would like to have a view for every 15minutes. Why? Because in Belgium they will start with a new way of calcaluting our bills by checking if we exceed a number of kWh during 15 minutes. Offcourse I can create some rule for this, and I will probably do so, for displaying it in other widget, but it’s nice to see this in a chart.

Much will depend on the persistence you are using. rrd4j will not work well for this as things get aggregated and averaged quickly. If you use Influx and Grafana, you should be able to definne the graph to show in 15 min max values.
I do think a rule makes sense to create a separate time series.I also don’t what the right interval boundaries are. Is it at h, h+15 … or is the starting point defined differently?
I still have a rotating meter, but will be confronted with the same issue one of these days ( I hope as late as possible). That combined with a solar panels, an EV and a heathpump makes this critical for me to keep my bill reasonable.

I created a small powershell script to calculate the peak power from the export of Fluvius (15min totals) and when I take the highest value of each month and multiply it by 4, I get exactly the same results as the website of Fluvius displays. So I can conclude they intervals are h, h+15, h+30, h+45.
I have the data of my digital meter in both rrd4j & influx, I only write the values every 5 minutes to influx, but the values are more or less correct. Maybe I need to change this to every minute or every change (I pull the values every 10sec for viewing live concumption).

I just discovered that the digital meter is already returning the peak consumption, so actually no own calculation is needed… code 1.6.0

As far as I know rrd4j persists every minute. How do you provide the consumption every minute if you read the values every 10s?

I only have a different setup for writing to influxdb. rrd4j is setup as default. I only use the 10s values for displaying my live elektricity usage, pv production, battery (dis)charge.