If only life were so clear cut.
Sadly the reality isn't that poor = low use and rich = high use. The more you're at home, the more likely you are to have big energy bills. The more people that are at home, the more likely you are to have big energy bills.
Also, tiered pricing would have to be mandatory to work. If it's optional, why would a household with high energy use join the tariff?
Dress it up whatever way you like, the concept is still the same. I get that there's a romantic notion of ensuring people who are wasteful subsidise those who are frugal. There's probably a mental image in there of some middle-aged couple chilling in a hot tub. But the reality is that said couple would simply turn the tub off, or install their own generation and/or a battery. The bulk of those who would be paying more are families, pensioners, the disabled. All so that someone who lives alone and works long hours (but not from home) can have a nice subsidy on their bill.
Sorry, but the idea is trash.
The very poor are on pre-pay meters, where units cost more (no direct debit discount and higher overheads). They tend to be very, very careful on their usage because they can't afford not to be. The reality is while there are outliers, poor people will use less electricity than rich people who don't monitor their usage, as there is no need for them to worry. Poor people, pensioners and the disabled will also tend to live in smaller properties, which need less units to heat, and as such, will use less units.
The more people in the house, the more units are used, agreed and what is your point? The higher users should pay more, or cut their usage to reduce demand and the wholesale price.
So make it mandatory and anyone that is on a variable standard tariff gets moved on to the tiered tariff.
If they turn the hotub off, or install their own generation and/or a battery, the usage would be reduced and as such would reduce demand and the wholesale price. Don't see the problem.
Why shouldn't someone who lives alone and works long hours have a subsidy on their bill if they don't use a lot of units?
The reality is very much, poor people use less units, rich people use more.