Splitting an Input over time

My immersion heater now heats water at night (Octopus Go cheap rate) and during the day (excess solar PV). If I want to record the kWh of both would it be best (or even possible) to do this within emonCMS, or would I be better off doing it within Node-RED and re-importing back in to EmonCMS? I can’t see a suitable Process within emonCMS to use.

I just need to have two Feeds, one between 00:00-04:30 and another 04:30-23:59.