The considerable fluctuation of normal usage would make such a
comparison rather meaningless in the context of what Jodie is trying to
achieve.

Regards,
Emrys Davies.



"Richard Brooks" wrote in message
...
Jodie wrote:
Have a nice new electrical greenhouse heater. Its set to
automatically start and stop with temperature.
So as to calculate power use and hence cost of greenhouse heating
anyone know of a good inexpensive system of recording the duration
the heater was actually on?
Thanks

Could you not use a cheap paraffin heater for a few days (to keep the
cacti
happy in the meantime), measure each days power usage on your meter
for
normal usage, then plug your new electric heater in, monitor the power
each
day for the same period as without electric heating then take two
averages,
without electric heatng and with electric heating ?


Richard.