Adrian wrote:
In message , Theo
writes

https://openenergymonitor.org/
does it on a Pi, and will sell you the parts need to hook up to your meter
for not-very-much.


Looks interesting, but (so far as I can see) only works for electricity
metering, not gas.

Gas is tricky - it's hard to measure without interposing something in the
flow (or maybe Doppler ultrasound?). That means you're left trying to read
the exist meter optically - does it give a pulse or something a sensor could
be attached to? Apparently it's illegal to strap on sensors, but a
non-contact way to read it might be feasible - worst case a camera pointed
at the digits. It would likely need to be tailored to whatever meter you
have.

Given that I don't have a power socket next to the meter, and I've
already got several Pis running, would it be feasible to get the sensor
head, and use the wireless to talk to an existing Pi ? (the site
suggests it might be)

They have a module which is battery-powered and does the metering, and
talks by radio (433MHz I think) to a Pi.

Theo