Depends where you are in the world.
Like you, I'm in the UK, more specifically in England, and that's what I'm talking about.
Not sure what the UK rules are, but I know that to get a mortgage, the dwelling needs to have a water supply and a kitchen and bathroom in-situ.
I can well believe that, and it makes some sense, but it's got nothing to do with 'what is required'. I was recently talking to a mortgage broker that some lenders are very reluctant to give mortgages on houses with Artex! What mortgage lenders are concerned about is the 'sellability' (and value) of a property if they have to repossess it, and the absence of what most people would regard as 'essential utilities' would therefore be expected to put them off in a big way.
I'm sure that there must be some of our 'very green' friends living in (un-mortgaged) dwellings in the middle of nowhere without any formal utility supplies (gas, electricity, water, sewage etc.) at all, and I don't think that that, per se, necessarily means that they are in violation of any rules, laws or regulations (provided they have the necessary 'permissions', like Planning consent).
If you are a tenant in California, all appliances provided under the tenancy must work, including heating and cooling appliances, like a furnace, A/C and fridges/ freezers.
For all I know, the same could well be true of rented accommodation in the UK - it certainly wouldn't be unreasonable. However, that is again different from the question of whether it is allowable, per se, to have a house without an electricity supply, or without lighting circuits.
I know it's not the UK, but my other half has some elderly relatives in rural Ireland (Eire) who have no electricity or piped gas (and maybe not piped water - since I know they have a well) - and so are reliant for everything on solid fuel, cans of oil and bottled gas.
Kind Regards, John