Hi again, Dave

I've completed my house renovation but have kept my partial underfloor heating from a condensing gas boiler. The trouble with underfloor is it only works on the most modern builds with high insulation and air tightness. I have 18mm wood over concrete screed and have calculated 80w m^-2 output - which is about 30w short so I top up with a convector gas fire. I looked at running additional rads from the manifold but at 45c flow temperature the deltaT is less than half that of a conventional primary flow so the radiator would need to be over 2x bigger, not 20%. ( 45-21 room vs 75-21 ).
I have noted the effectiveness of primary window draught proofing ( especially on the old leaded lights ), secondary glazing, under suspended wooden floor celotex and caulking, sealing over downlighter holes with fibre loft caps ( and replacing the bulbs with Osram Decostar IRC 20/35w which give exactly the same lumen, temp and CRI output but use 40% less energy and project all their heat downwards ). All I need to do now is swap my wife for a low energy version :)
On the control side I have a full weather controlled modulating system. It lowers the rad temps as the demand lowers calculated as a function of outside, inside and target temp in the 4 zones. It learns the response time of the house and will start heating earlier if it's cold and never come on at all if there is a sudden warm spell.
I also chose a boiler that will run off propane if needed and remote pumped showers from oversized tanks in case of intermittent water supply.

I think we need to be careful to distinguish not only between individual and collective actions but the impacts of not doing so on both levels. If there are intermittent power cuts then me having genset/battery backup is a valid option but if power become chronically unreliable then even the most extensive off-grid system won't bring food to your table or stop others coming to take yours.
My experience in South Africa is that communities will stratify by wealth as security deteriorates as a function of employment and resources.
By all means set up for intermittent power outages, even keep a week or two of food and water on hand but realistically if circumstances go beyond that then nothing short of an armed enclave will give you total security.
Having a brightly lit, warm house with food on the table in a cold, dark neighbourhood of people with starving children is not a recipe for success.
There is no option but to be strategic about this and reduce demand. Whether that is ration by price or by smart meter, efficiency grants, programs and leglislation or otherwise across all resource types is a matter of debate.
Unless we abandon any pretence to democracy and revert to an almost feudal society with rent paying serfs maintaining a gated landlord class and avoiding the armed guards.
Like Russia, Brazil, China and South Africa then. Great :(