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Comment by WithinReason | Hacker News Reader

Sure, but will the unintended consequences be worse than not importing 8% of UK energy from North Africa? Because that will have consequences too.

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It’s a bandaid solution for the UK to maintain growth sans environmental consequences.

Maybe that’s okay if North Africans own the means of production and transmission giving them the ability to turn those consequences into opportunities elsewhere.

How about cutting down UK energy consumption by 20-30%?

How could that be done?

Lots of comments on hackernews/reddit appears to be the go-to method thus far.

Insulating houses and offices (windows, roofs, walls).

Imposing more stringent insulation and energy requirements on new builds.

The UK housing stock is very badly insulated.

Yes, insulate as well. But a person living in a single glazed warehouse conversion with no insulation but next to a tube stop and a food shop will use quite a bit less energy overall than a person who lives in a passive house but has to drive 10miles to work. Restoring walkable town centres and discouraging car use in towns and cities that worked fine before cars would save more energy and would be quicker and less disruptive than trying to insulate every old victorian house. Insulating old houses is technically hard to do right and different houses need different solutions. If it’s done badly it will cause health problems from black mould and structural problems from condensation causing timber joists and rafters to rot where they pass through the insulation into the masonry walls.

Sure I agree liveable city neighbourhoods are also a good goal, one the UK gets right a lot of the time (certainly more so than the US for example).

Re bad insulation, don’t do that then, a gov scheme with regulated contractors could ensure that but it is much better to use less energy heating old leaky homes.

PS Insulating 19C housing can be done well, here is a good example: https://historicengland.org.uk/research/heritage-counts/2019...

Insulation cut my mother's home energy costs by 60% this winter. And her home wasn't as poorly insulated as UK homes seems to be according to what I read (and in general, it was a bit above the average French home).

Granted, heating is around 15% of the total equivalent Co2 we use, but reducing that by 60% would prevent 8 to 9% of produced energy to be used. Also would cut costs for a lot of the poorest.

If insulating UK cost around the same price (or even more, because the windfall will be in UK taxpayer pockets), I think it should be done first.

UK home owner here. House is sticks and bricks, built 1920ish but heavily modernised. Insulated to modern building regs, including extra steels and structure to account for snow loading on the roof. When it snows here (very infrequent) our house is the only one that it sticks to. Also acoustically insulated between floors. Ground floor (first floor elsewhere) - we hung safety barrier netting between the joists and ran 125mm of loft insulation between the joists to insulate from below but still allows some air movement and avoid condensation.

Underfloor heating ... electrical underfloor heating - across the entire house. Now our theory was that if we got our 'leccy from renewables, we were pretty "green". We do have gas but that is only used for cooking (hobs only - not the oven) and hot water.

When say our kitchen floor decides to switch on, that's 4KW. Each room has its own circuit and we switch off the unused ones. After a power cut the blasted things revert to defaults and switch themselves back on, I have to cut them off at the consumer unit to be sure. I am three years into experimenting with Zwave zone controllers but they cost a fair bit and I need to be absolutely sure about safety before I deploy all 10 zones. I'll probably install a separate cut off switch per zone with a few temperature probes as well as the controllers with their own sensors but that is a while off for now. Home Assistant with Node-Red runs this lot and more. Safe power control does need some care ...

Electricity here is roughly three times more expensive and rising than it was before a bunch of homicidal Russians decided to fuck up their neighbours. My bills are quite heavy and it doesn't help that I run quite a lot of IT stuff here! I'm very lucky that I can afford all this but not everyone can.

I don't think that UK housing, in general, is any worse than the rest of Europe with respect to insulation. I lived in West Germany for some time back in the day and I studied Civil Engineering so I think I have a fair handle on the issues involved. We have just as many horrors in our housing stock as everyone else.

Interesting, I'm in a house of a similar age/construction but not very well insulated apart from the loft. Have you written up any more information at all; costs too? Assuming you have a cavity wall, did you insulate that?

I'm a bit wary about filling the external wall with polystyrene balls or whatever. I need to determine whether there are enough brick ties installed and that they are working. Brick ties are basically bits of heavy wire that should be laid in the mortar that hold the two rows of bricks together.

The idea of filling the cavities of a fairly old brick built building with some form of insulation is sound but does need care. In the UK (and elsewhere too) we generally go for "sticks and bricks" construction. The external "box" is often a double skin of brickwork. My house is roughly six meters by 12 meters (20' x 40') in plan. Each storey is about 2.5m high - that's why you see wood in 2.4m lengths (allow for bits above and below).

So let's look at the structural components: Take a wall 12m long x 5m high. The wall is constructed of two skins of brickwork. Brickwork is very good in compression but not so good in response to a lateral force. If wind is allowed to whistle inside our brickwork it will basically raise the pressure inside the gap between the two skins of brick. If you pump something into the gap that will also exert a lateral force. To stop your walls collapsing outwards, you should have brick ties installed and they should be in reasonable condition and the mortar should be gripping them effectively.

You can go for external or internal insulation instead. External means cladding of some sort and internal means you will lose some internal floor space.

The biggest gain of all is insulating the loft - heat rises. You should aim for a good 250mm of "wooley" or equivalent.

In general I'd suggest looking for draughts and plugging them. Do be careful that ventilation is still maintained.

Increased heating efficiency (heat pumps, insulation, solar water heaters, etc)

More public transport (including less cars AND EV cars)

Less frantic production, transportation, storage, and consumption of useless throwaway crap

and several other things besides...

Why not try to do both?

That is completely impossible. The UK uses 5x as much energy as it currently generates in electricity, mostly for heating and transport.

I'm not saying that laying cable from Africa to the UK is the best solution, only that the UK needs a solution if it is to go net zero.

Why not both? Even if the UK does that, we still need far more green energy to stop putting carbon in the atmosphere.

UK per capita energy consumption has been declining for a while. This is pretty typical in the developed world, largely driven by efficiency gains.

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