PowerSwitch

I have recently heard of a number of cases in which electricity meters have been replaced, and the available supply capacity has been discreetly reduced at the same time.

The great majority of UK domestic supplies are single phase at 60 amps, 80 amps, or 100 amps. A very few are only 40 amps, and I have found a couple of 20 amp supplies.

When a new meter is fitted it seems to be a common practice to downrate 100 amp supplies to 80 amps and to reduce 80 amp supplies to 60 amps. This is sometimes said to be for safety reasons because the meter tails are claimed to be inadequate even when these were installed by the DNO.
Downrating seems to be only applied to the less technically knowledgeable customers and/or those with a limited demand.

A cynic might suspect that if the DNO can "get away" with reducing the supply capacity, then in years to come they might expect a very fat fee for an "upgrade" to that which had historically been provided.

60 amps now seems to be the default choice for new builds, rather than the previous default of 80 amps with gas available or 100 amps with no gas.

Could this be a case of "negawatts" in action: ensuring that there is less electricity used in future to safeguard the supply at a lower level of demand so that existing supply is adequate from existing sources?

kenneal wrote: ↑26 Nov 2020, 13:46 Could this be a case of "negawatts" in action: ensuring that there is less electricity used in future to safeguard the supply at a lower level of demand so that existing supply is adequate from existing sources?

This may well be the case but of course this can not be squared with the vision of a widespread
take up of home EV charging and replacement of gas central heating with heat pumps.

I suspect a cynical ploy to charge a large fee in the future for "upgrading the supply" to that which was previously existing.
If the customer appears technically informed or takes an interest in the work, then the existing supply capacity tends to be retained.
"little old ladies" tend to have the supply capacity reduced. The next owner of the property can then be charged for "network improvements"

A supply restricted to 60 amps is borderline for chargeing an EV as a domestic fast charger requires 30/32 amps.
A small supply also discourages use of electric showers and other instantaneous electric water heaters, these are in fact a sensible way of heating water for the smaller household.
A 40 amp electric shower and a 32 amp EV charger are obviously unwise on a 60 amp supply, and marginal on an 80 amp supply.

I wonder if it could be due to a lack of plans to upgrade the local networks and with the growth in new housing developments then the same power has to be split between more households. On a street by street basis what I said would not make a lot of sense but on a larger scale it would make sense for downgrades to be made to avoid upgrading the distribution networks at maybe the 11kV level.

I remember a while ago the M25 was 'upgraded' to four lanes from three by repainting the lines and making the lanes narrower. Similar it seems with parking spaces etc.

Last night I was doing a night shift at an aluminium smelter and there was a 32 Amp breaker getting hot as it was taking 31 Amps. We upgraded to 40 Amps. I don't think they have a supply problem though. They have 4 circuits of 330 kV lines coming in and use 950 Megawatts. Surprising how powerful the magnetic fields are near the DC busbars. They fling metal doors open and makes your screwdriver stick to steel cabinets and stand up.
This smelter had to cut power for one hour on two of three 'potlines' yesterday. There was a shortage of power in New South Wales in early evening.