DavecUK
DavecUK we pretend to be a 230V country when in fact we are 240V w
Well, the pretence must run pretty deep, as the median voltage is currently 232v in the UK. If you’re beyond a power stations direct catchment outside of peak hours then you may even be below 230v, but if it’s 0850 on a weekday morning and you happen to live over the road form a gas powered station, you’re possibly getting 250v~.
I recently did some voltage/usage logging for a plastics factory and they had a swing of about 18v (I seem to remember). They are now forking out tens of thousands of pounds on voltage optimisers.
My PV grid monitor has had a variance of 11v today.
Some parts of the grid use capacitor banks to try and keep voltage more consistent.
A 5% voltage variance on a heating element is at worst, negligible, unless it’s a highly precise heater it’ll vary in terms of output based on the added resistance while under load.
But anyway, subscription services are, in my opinion rarely good value!