On 15/11/2020 12:35, Roger Mills wrote:
Prompted by the Smart Meter 2 thread, it occurred to me to wonder
whether there was any way in which I could monitor my electricity
consumption in half-hour intervals in order to evaluate whether one of
these fancy tariffs would be good or bad.

[Before I had a water meter fitted by my water company, I fitted my own
meter and ran it for a year or so to see whether I would be better or
worse off with a meter.]

You can buy energy monitors which either use a clamp sensor round one of
the meter tails or count flashes on new-type meters. But they only
appear to give instantaneous readings and daily totals.

Does anyone know of anything more granular - preferable with the ability
to capture the data and insert it into a spreadsheet? Sounds maybe like
a Raspberry Pi application?

If I were to have a smart meter fitted (which I've hitherto resisted!)
but to stay on a fixed tariff, could this be made to provide me with the
required data?

If you have a fairly modern electricity meter with the flashing led on
the front, each flash corresponds to 1Wh consumed. Just count them for
each time period and job done. The meter does all the volts and current
conversion and cos phi phase angle correction for you.