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Ask HN: How much gas we could save in EU if we reduce our heating temp by 3°?
151 points by ciccionamente on Feb 26, 2022 | hide | past | favorite | 240 comments
This question is related to the potential SWIFT block that might happen any time soon.

It sounds maybe naive but I was thinking that if we almost all turn down our heating system by ~3° Celsius (compared to our current settings) we could potentially save gas consumption that can be better used for other purposes. What do you think?

23% ish.

It's not naive. Going to "pure" building science (I studied this in uni) the formula for the building heat loss is Q=U.A.dT where dT is the temperature difference between indoors and the outdoors.

If you assume that outdoors is 5°C on average in year, and indoors is 21°C, dT is 16. reducing the indoor temp to 18°C puts the dT at 13.

Since everything else stays the same, you'd expect a 23% decrease in heat loss (Q). And that much less energy need to be replenished.

In the real world buildings are more complicated than that. Also you may risk giving more people diseases and reduce cognitive abilities when things get cold. So perhaps also tell the public to dress warmer and drink more hot fluids.

In my opinion, it is naive.

First of all, the average yearly temperature means nothing for indoor heating. Suppose this average is 20°C: it could be half of the year at 5°C and half at 35°. It's even more complex, for instance if cold days and hot days alternate they have very little impact. The heating is mostly needed when the temperature stays low several days in a row.

Then, there are external sources of heat, like sun or human heat. They can increase the indoor temperature for a few degrees. I worked for years in an office, facing South, with no heating even when it was freezing outside, and it was okay.

Finally, the formula does not imply what you said. In plain words, it means the energy (heat) is proportional to the mass and the temperature difference. The factor depends on the material. So it does mean that increasing the temperature of 13° instead of 16° uses about 23% less energy. But it does not mean that this much energy is needed to keep this temperature inside a building. Suppose that, with an external temperature of 7° (the average for my city for February) an insulated building at 20° would lose 5° a day. Then dT=5 in the formula above. Whereas the same building at 17° would lose 3° per day, so dT=3, a 40% decrease in the energy needed.

In my opinion, there are too many factors to give a simple answer. It know it's possible to estimate this for a single building, given a proper model of the weather and sun exposure, but it is hard to generalize from an individual response.

your comment about average yearly temperatures is of course correct, but in this case it biases in favour of GP:

* It's colder than average today, to reducing the setpoint has more effect vs an annual average. If sun takes part of the heating, then the ratio of dT to gas saved is even bigger.

* The formula actually does work that way, maybe you're thinking of a different formula? i.e. Q (flow of heat) is a function of some heat transfer coefficient (U), area (A) and the temperature difference (dT) between inside and outside. So the (simple) correlation between dT and gas consumption to maintain a temperature is linear. This will be influenced by e.g. wind (increases U, therefore gas consumption) and other factors of course.

Anyway, it's winter. If there is any time where you can reasonably reduce your gas consumption by lowering the thermostat, it's today. In fact, I'll try this now and see if it works. Maybe time to start a movement.

(Also note that residential heating and office account for roughly a third of gas consumption in e.g. the Netherlands. Reducing that by 20% is still 7% reduction in total, and potentially a 17.5% reduction in Russian gas given the current gas mix)

In the US, heating energy loads are calculated on degree-days.

This captures the expected dT on days when heating is required and ignores days when heating is not used. In the summer for example...

...except in the US cooling is also common so it actually captures both heating and cooling and involves multiple energy sources in many locations...which brings up that degree-days are highly variable at the local level -- consider the difference between Norway and Greece in the EU.

degree-day https://www.eia.gov/energyexplained/units-and-calculators/de...

Same in Europe, at least in Denmark. Source: my dad is a civil engineer who has been doing renewables since the oil crisis in the 1970’es.

US figures are available which can tell you both heating-degree-days and cooling-degree-days.

What technology are we missing to be able to ship heat from warm houses to cool houses?

> Also you may risk giving more people diseases

This is an old wife's tale. Especially at 18C. No one is going to be getting diseases.

I think when you're calling bullshit, in order for it not to become a he-said, she-said situation, you should provide any sort of source.

If you sit still at 18°C, working on a computer, you'll get very cold before the ~3h of work in the morning is over if you don't also adjust your clothing. I don't find it such a leap to assume this body temperature change reduces your immune system, but then I don't really know. I'd be interested in the answer, but at this point OP's argument makes more sense to me than yours and neither is backed up with links so...

> if you don't also adjust your clothing

That's the thing though. If you live in an area where heating is required in the winter, you definitely have the necessary clothing to get through a period of 18 °C in your home.

You could take the terrible example we live by here in New Zealand. We pretend it doesn’t get cold, have poorly insulated and rather damp houses and just suffer through it. An inside temperature of 18 in midwinter sounds lovely. We also lack good wardrobes, but that might just be me.

NZ housing stock is truly atrocious. I knew it was bad but didn't appreciate how bad until living in the UK and going through winters sometimes without even needing to use heating (granted in apartments in that situation). Double glazing being near universal compared to pathetic aluminium frames are a major difference and leaky buildings top it off.

Looked at emigrating to NZ shortly after the kids were born - so many friends had.

I was shocked by the housing situation, prices were going crazy sure, that’s to be expected, but the actual quality of the housing was also terrible, and there wasn’t any cultural awareness of how bad they were

Didn’t move in the end, mainly because we wouldn’t have the money for the kids to see grandparents. Still not sure it was the right decision.

I considered NZ as well but the weather looks pretty terrible in NZ (maybe slightly better than the UK), windy and rainy.

House prices weren't too bad but quality wise they weren't great. I can't say they were much worse from London tbh (but it may be more related to how everything is expensive in London, outside of London house quality is way better).

Also taxes are pretty bad.

I'm completely appalled at how they're dealing with COVID so I'm glad I kept away from NZ and AU

Not sure about the weather comparison with the UK - its a lot wetter but the weather is more tropical (ie we get the rain in massive downpours, not drizzle).

House prices are very very high relative to wages and the quality is deeply average. Comparing house prices to London is not very logical, as the wages are nowhere near the same.

Dealing with covid - compare the death rate to pretty much anywhere. That was the point and what we wanted.

Any moves to tighten up building regulation are derided as red tape, nanny state etc. It’s amazing how much we undermine ourselves.

I grew up, and spent most of my life in Canada. I moved to Australia in my 30's. I have to say, I have never had a more uncomfortable winter than my first year here. I was cold all the time. Down to my bones cold. I hated it.

I eventually found a house that had decent insulation, and since then I've never let it get cold in my place. I've got solar, and I keep the heat cranked.

Even with more layers 18°C is low enough to impact joint movement which makes it difficult, even in healthy young people, to type on a keyboard. Similar to how summer heat without A/C interferes with concentration. Brave personal sacrifices to save the planet.

Indeed. There's no way I can work at 18°C. Four layers of shirts plus wrist warmers won't be enough to keep my fingers flexible on the keyboard if I sit still and code.

Edit: and I know this because I start the workday at 17°C in winter months. I live in an old building with poor-ish window insulation so I turn off heating in most rooms for the night, and in the bedroom for the day to conserve energy.

Code on a laptop and mine verium on it too (or whatever, 'compile') + an incandescent bulb aimed at your head is a decent amount of mitigation for it being 17-18C.

During the cold snap where it was below -15C during the night in the southern US last year I did exactly what i specified, and i didn't bother using my central heat. I haven't used central heat at all for 2 years. I do have mini split air systems, but at -15C they spend more time defrosting than heating, so the mitigation was to use lots of blankets in the bedrooms and turn the minisplits to heat at about 6AM to take the chill out for the morning routines, but shut them off at 10PM. There's no sense in wasting heat defrosting on "less efficient" heat pumps.

for perspective it's about 19C(66.2F) and i'm wearing shorts and a short sleeve shirt, indoors. One other thing that may not be true everywhere is i run de-humidifiers nearly year round, so that does dump about 800-1000W in the air when they're actively removing moisture, so your mileage may vary.

Thanks for the tips, but not very applicable in my situation. I never use the laptop keyboard, but rather an external ergonomic keyboard.

Building is from 1910s with central heating that I can control for my apartment, so doesn't affect my electric bill directly. Any form of electric heating would likely be more expensive.

Finally, I start wearing shorts and t-shirts at around 25°C, and my favourite indoor temp in summer is 27°C so I guess you're just better adapted for cooler weather.

> During the cold snap where it was below -15C during the night [...] and i didn't bother using my central heat. I haven't used central heat at all for 2 years. [...] i'm wearing shorts and a short sleeve shirt, indoors

Yeah something doesn't add up here. Unless that lamp has a crazy wattage and you look down at this "mining" laptop on your lap for 8 hours a day (no desk, all heat going to legs, wrists, and hands), I don't really see this being realistic.

75W halogen, but my laptop can dissipate 170W. As long as you don't have fans blowing air around/over you, it's fine. your basal metabolic rate can be captured with clothing and especially caps, like a thin fabric cap and then a wool beanie/cap over that. Plus ~200ish watts of heat where you need it, head and hands.

I do have to use more heating if the temperature stays below 4C or so for more than 24 hours. That is, my indoor ambient temp was 11-12C on the night it was -15C outside - had it remained that cold for longer than a night i would have had to raise the indoor temp with electric heat, as mentioned, the split-air was woefully inadequate. I was just trying to avoid the central electric heat since it smells bad the first few times you use it in a season and it always wakes everyone up.

all this being said, people are different and my wife and son would have been miserable in the exact same situation. I was speaking directly to "fingers get too cold to type" with the laptop thing.

Lol, we use 3W LEDs for lighting... And not gonna change that with the electricity prices of today. And my M1 never gets hot and has no fans...

That's fine, however, if you're using heat at all in your home, having a "mining laptop" and a few incandescent lights around to take the chill off is not going to increase your electricity bill, unless you're using gas for heat. I forget the ranking of efficiency, heat pumps are more efficient than resistive heating (to a point well below -15 for more expensive units); however i forget where gas fits in that spectrum.

having a couple hundred watts of heat per person will lower your overall heating bill, all else being equal.

Of course I use gas for heat, most people do here. Electricity is way too expensive to heat with it, even for a programmer.

I had never heard of the term wrist warmer! Just image-searched it, that looks great. I've tried fingerless gloves before (some family members have those for sailing) but those make it hard to type and I dropped that attempt. Will be seeing if I can buy some of those, or maybe repurpose some old gloves. Thanks for that :)

> I start the workday at 17°C in winter months. I live in an old building with poor-ish window insulation

That might also be your problem rather than the temperature. If there is any amount of air movement, like even just air being refreshed so to say, that takes away any lingering heat and replaces it with new, cold air. Of course, everyone's internal thermostat also works differently so I'm not saying this must be it but... something to consider.

> That might also be your problem rather than the temperature.

Yes, very possible. The windows have basic insulation but there is a small draft for sure. I'm renting so I'm not going to do any window renovations though.

Healthy young person here: joints are not a problem at 17°C, though I do pack myself in comfortably thick and warm clothing so a lot of that will make it into my (uncovered) hands. For me 17 is the limit, but definitely not yet problematic.

I do notice in the morning if I forget to turn on the heater (we're on the ground floor but sandwiched between neighbors who seem to keep it toastier) and the room is ~15°C. It takes an hour before I get cold after coming out of bed, but then, yup, typing is one of the things I notice after that time.

My living room is 18C when I wake up and I still have to tell my kids to get dressed and not veer around in boxer shorts before I start the heating.

The bedrooms are colder BTW.

> I think when you're calling bullshit, in order for it not to become a he-said, she-said situation, you should provide any sort of source.

You have it backwards. I'm saying there's no difference. The person making the claim there is a difference is the one who needs evidence.

I get a runny nose if I get cold. Same for my children. From an energy perspective, this make sense. If the body is expending more energy trying to get warm or not get cold, it may not have the necessary energy to fight off germs.

Also, the immune system works better hot, aka fever. Cooling the body can be expected to suppress the immune system.

Before you dismiss proverbs (old wives’ tales), consider that they could persist because they’re true.

> I get a runny nose if I get cold.

I was curious, so I looked it up, and according to [1] and [2], that's a natural reaction to help the nose turn cold, dry air into warm, moist air.

"When cold air enters the nose, it stimulates the sensory nerves within the nasal cavity to activate a process via a cholinergic reflex or pathway. It causes the vessels in the nasal cavity to expand and become engorged, leading to congestion and mucus secretion which produces a runny nose. It’s a compensatory mechanism that’s trying to maintain ideal conditions inside the nose by adding humidity and warmth while filtering the air."

1: https://medicine.uq.edu.au/article/2017/10/why-does-your-nos...

2: https://wexnermedical.osu.edu/blog/is-the-cold-weather-causi...

I would like to see a source on that, but the human body is orders of magnitude more complex than to reason about things like “it has to expend more energy” and “fever is good”. You could pretty much derive every effect from every input with these low level “conclusions”.

We have evidence-based medicine exactly because even when it would seem logical, biology puts a curve on that and the opposite of the intended effect happens.

Dress up.

Good study of excess winter deaths in Europe:


>most countries suffer from 5% to 30% excess winter mortality

>The strong, positive relation with environmental temperature and strong negative relation with thermal efficiency indicate that housing standards in southern and western Europe play strong parts in such seasonality

This isn't supporting evidence. It says nothing about the impact of lower temperatures on your immune system. It's a correlation with total mortality which could be caused by many other unrelated things.

You can't use the average.

Example: Let's say for half year the average temperature is 11°C and for half year it's 31°C. That gives an average temp of 21°C and a δT of 0, even though you would still need to heat for half a year.

i assume the 5C average is the average for the heating season, not for the whole year.

Then you have the day-night cycle

Don't forget hot water bottles. Excellent recent post from Low Tech Magazine on this:


tl;dr is that heating people rather than spaces is a great idea with much more mileage than we give it credit for.


It's widely accepted that ebikes are some of the most energy efficient personal transport possible, because they're moving so little vehicle mass relative to passenger payload. Just 250 watts can give you rapid enough point to point mobility for trips up to 10 miles or so.

In the same way, heating and insulating people is vastly more efficient than heating air and brick walls. 100w of active electric heating together with a couple of layers of clothing is plenty to keep most people pretty comfortable at an ambient temperature of 14-15c.

I'll try using one as a wrist rest. In a cold room I can dress warm, but can't type with gloves on. The Jayne Mansfield hot water bottle would warm me up in more ways than one!

Electric blankets are great too. The model I have only consumes 60W.

> Also you may risk giving more people diseases and reduce cognitive abilities when things get cold.

Could you explain this part? This is exactly opposite of what I've seen my entire life.

Yes, many people argue that they function better in the cold. That very well may be true. People's metabolism and feelings are very different.

That's taking about what's generally accepted. The body of literature in this field defines a "comfort zone" that spans around and above 20°C. it's been studied that with better comfort there is better attention. Also being cold appears to weaken the immune system.

Mine and everyone I know's immune system is strengthened, not weakened, by cold.

It "appears" to weaken by giving it a run to its knees, but actually making it stronger while doing that.

If you expose yourself to more cold, you start never getting ill.

Older people have much weaker immune systems that aren’t strengthened when it gets cold. HK lacks central heating, and a bunch of older people died when they had a cold snap that took them down to 5C. If you think your immune system is helped by being cold all the time, southern China during the winter is the place for you! It’s amazing how constantly being continuously exposed to non freezing but still cold room temperatures can really mess up your immune system.

This is incredibly naive. The only non-naive thing is that it is proportional to ΔT, which is simple Physics. I don’t know why you need to quote building science here.

For non naive calculation, one would expect using real world data to estimate the actual weighted average.

I mean it is ok to have a naive guesstimate, or to sound better, a Fermi estimate. But for order of magnitude guesstimate, just use 1 sig fig to convey you really don’t have that much confidence.

Also I think while providing a ratio is technically answering the question, but people probably expect the absolute scale, in terms of $ or may be a ratio comparing to annual spending (given a country.)

I think in short this is not a simple question and we should not pretend it to have simple answer.

More precisely you say that we would save 23% of our heating expenses. But not all of our heating is from gas, and gas is not exclusively used for heating. So this is only a first step towards answering the original question.

Occupied gas heating. Many residences and almost all offices maintain lower setpoint when unoccupied.

It doesn't help as much in a cold snap though, which is peak gas demand. If it's -25C outside, each degree C is only ~2% change in delta T.

I'm all about dialing back the thermostat, but I've also noticed a huge comfort difference between 18C and 19C. Quality of life starts to nosedive for a few percent more saving; it's better to fix up your house.

As I understand it europe has significant gas storage capabilities. The cold snap creates a demand that can't be average out for things like last mile pipelines, but those aren't the limitation. Storage should allow for averaging gas usage over (I think) the whole winter to decide whether or not there is a problem.

I seem to recall running the HVAC system also doing some work to keep the humidity in the building low, and that being factored into building design - that sound right or ring any bells?

Shouldn’t be a factor in winter.

Even if this formula works, this would be 23% of heating consumption when buildings are occupied, not 23% of all heating consumption, and definitely not 23% of all gas usage.

You should start by checking if the flow temperature is set correctly

Many EU gas boilers are set too high, such that the boilers don't operate in condensing mode. You could save 6-8% gas by doing this: https://www.theheatinghub.co.uk/articles/turn-down-the-boile...

Octopus Energy has some further tips: https://octopus.energy/blog/winter-workout-gas-saving-tips/

Don't forget to try hugging your pets too!

3C is a lot if you're talking Celsius--but I do this at night (set thermostat to 60F-61F) as cold temps under layers of blanket is actually beneficial to sleeping.

Older houses sometimes still can benefit from insulation improvements.

So go in this order:

1. effective insulation

2. conscientious and smart use of energy and avoidance of very inefficient heating systems. avoid heating large areas when they don't really need to be at very warm temperatures. (careful though to avoid damp cold range of temperatures where wood rot and permanent damage to homes will happen). Avoid unburnt natural gas, eg in badly maintained or cheap cooktops. The ideal household kitchen has ~ 4 gas burners, and one or two induction burners flush with the counter, eg https://www.amazon.com/Countertop-Portable-Induction-170-Min... This minimizes unlit gas for those very short heating needs in the kitchen.

3. think about upgrading to very efficient systems. These most promising could be (depending on your area and scale of heating needs):

-- electric-heat cogeneration

-- heat pumps that use the large volume of ground underneath the basement as geothermal heat-mass reservoir. Heat the ground mass during the summer to provide AC, and squirrel away the cold thermal mass during late fall and late winter+spring.

1.5: wherever possible, heat people and not rooms. The BedJet is one easy example of this, but there are others.

thanks. that is a great idea. Sweet that this can be run for cooling too. (I sleep horribly in the summer because it often doesn't cool down enough and I feel bad about running the AC for too much time.)

Who leaves their heating on at night?

When saying things like this, it is better to contextualize by giving some information about where you live. Some people live in areas where temperatures go as low as -20~30 C and not leaving the heating on can damage the house infrastructure. In other areas, where the temperatures only go down to -2~3C, you can get away with never turning the heating on.

Who doesn't? Near zero temperatures outside mean that it gets cold awfully quickly and with sub-zero temperatures there is lot of risks with pipes and so on.

Sure but you just set the heating to 12C or something. There's no need to leave it fully on at 20C.

If you have floor heating + heat pump, then the manufacturer recommendation is to keep it running 24/7 from October to April. That's for the climate where I live, elsewhere this period may be shorter.

Why though? Is it to not have disappointed customers because it takes 4 hours to heat up and it's harder to explain to people how to set a timer to turn on at 3am, or because keeping a higher temperature delta between indoors and outdoors is actually more efficient with this system?

I don't know all the details and reasons, because I don't have enough knowledge about heat pumps. But the explanation given was that takes many hours for the whole system to 'warm up' and start working within optimal range. Turning it on and off frequently would actually make it perform worse, wasting more energy than if it's running all the time.

I'd wager it's to prevent damage if the stuff inside the pipes freezes/expands.

Floor heating won't go from heating temperatures (30°C? I don't know exactly) to freezing across 8 hours of sleep, even if it's -25°C outside.

The advice also doesn't have to be "turn it off", just "turn it down to 5°C" which would be safe indefinitely. There has to be another reason why the advice is to keep heating 24/7.

The controls available aren't in the sense of thermostats - for example, you can't ask it to keep temperature at 21 degrees during the day and 18 degrees during the night. Instead, it has something called 'heating profiles'. There are summer (passive cooling, essentially) and winter profile (heating). And for the winter profile you can set the level of heating: from -5 to +5 degrees compared to what it considers optimal. I have mine always set to -5, because even at that setting it's warm enough. Note that 'degrees' in this instance is not the air temperature in the rooms, but I believe the water temperature in the pipes.

In other words, it will automatically adjust depending on the time of day, temperature outside, etc. It is possible to influence how it works, via 'administrator' settings meant for the repair guys, but I haven't touched those.

Well that just sounds like a badly designed heating system then.

I have radiant floor heating, and setting the thermostat to my target temperature 3 hours before wake-up is fine.

But note that the OP has not just radiant floors, but also a heat pump (which isn’t using gas, so we’re far afield from the overall question, but setting that aside).

Heat pump systems are generally sized so that compressor’s sweet spot is pretty close to your expected normal/max output.

To be honest, this is more about the lifespan of the compressor than it is energy efficiency, but there is also a small loss of efficiency if you get the system into a state where it’s turning on/off frequently.

So it seems plausible and sensible that a radiant-heat pump system would recommend circulating 24/7 in the winter rather than cycling on/off a lot.

I don't know. It's not what I was used to before in my previous homes (thermostats in different rooms, specific temperature settings, etc.), but you know what? It keeps me warm and is cheapest heating I've ever had to pay for, by far.

My house has district heating, feeding into floor.. turning heat up/down takes effect many hours later.

House is also well insulated, with heat recycling ventilation. Objective is to keep a consistent temperature.

Every places I lived at in Germany the heating system is turned off at night for the entire building. Same in Switzerland. I always assumed that was the norm?

Not off. Throttled down.

Thanks for correcting, I just checked and you seem to be right

Many buildings hear use electricity for heating, electricity is cheaper at night. We have heaters that heat some kind of ceramic material and keeps releasing the heat during all the day.

Who doesn't? I keep my house at 23C. The cost is negligible. I don't want to wake up to pee and be shivering in the bathroom.

I do (suburbs of Seattle), otherwise my house would not stay above 17C overnight, especially with the last few nights we had.

Is there some reason why that's an issue if you're in bed? I live in the UK and well we don't put the heating on at night ever. Doesn't matter if it's a snowstorm or below freezing outside. Heating comes on first thing in the morning, but overnight you'd be pretty much fine in bed.

Yeah, you don't want to set the thermostat too low to protect the outdoor faucets (not all of them are freeze-proof, especially in the places where temps below freezing are uncommon). I also don't want to wait for 2hrs in the morning for the house to reach comfortable temperature, and would like to be able to go to the bathroom in the night w/o it being too cold.

Edit: is it more common to use forced-air heating where you live? Are buildings brick/concrete? Heating vía radiators w/ warm water and concrete buildings tend to have more inertia in my experience, the temp will not drop down that much overnight, but that's not the case in my current home.

Yeah, and that's the reason Irland and the UK is full of moldy shitholes.

Everytime I watched the housing offerings in Dublin I wondered how any sane being would spend upwards 1M£ for a small, moldy goat pen while parking their Porsche infront.

Isn't mold more to do with not airing out the house to let moisture out?

I've been keeping my house at 55F/13C this winter, not for money reasons, but because of climate change. Last winter I got used to 60F/15.5C, which now feels super warm and unnecessary.

So here's my advice for people:

1. Start today! Don't wait to see what happens in Ukraine. Lower your temperature by 1 degree right now. Just do it. 1 little degree isn't a big deal. Let your body acclimate to that. It'll happen on its own - our bodies constantly adjust to different temperatures throughout the year. Know that a temperature barely lower than you're used to won't give you hypothermia. It's not a threat to you. It's just a slightly different temperature so embrace it. Welcome the change, mentally choosing it. Once you're comfortable, lower the temperature again. Rinse and repeat. If you do this, you'll look back and be shocked at how you once thought a homeostasis temperature was necessary (or even desirable).

2. Eventually you'll feel the need for extra heating. The most efficient ways are directly heating the body through appropriate clothing and direct heat sources. For clothing, if you're cold, just add more. For direct heat, use a hot water bottle. You can also get an electric bed mattress pad. A heated mattress pad is amazing.

3. Warm food and drink: in summer, drink cold things. In winter, drink warm things. Eat warm foods like porridge (oatmeal/grits/cream of wheat/etc.), soup/stew, etc. When drinking, hold the hot mug in your hand. When eating, hold the hot bowl in your hand.

3. Water conservation - a lot of the water we use has been heated, for showers, washing hands, etc. Efficient showerheads and faucet aerators are CHEAP! Some of them have their usage etched into the side, if not, you can measure its flow rate with a measuring cup and a stopwatch. Once you know how much it uses, look into upgrades. When showering, turn the water on, get wet. Turn off the water. Soap your whole body, then wash the soap off. Now you're almost done with ~45 seconds of water use. It's easier in summer, but I'm now doing this in winter also.

Those are the basics and you'll get better with time. Eventually you'll be able to see heat like Dr. Manhattan sees atoms. You'll just see it everywhere, how it moves in and out of the system, and how you can harness and hold on to it, using it multiple times before it's gone.

55F is uncomfortably cold for many people. My heat goes down to 55F at night when I am bundled in bed.

My experience is that leak sealing based on results of blower air test brings nice heating use reduction while fixing the cold/drafty areas. After that take off window trim molding and spray foam both inside and out. Then apply extra insulation AFTER sealing. Maybe then another blower door test. If you start by replacing windows it will be expensive and less effective.

I hardly used any extra heating at all this winter, neither central heating nor spot heating. I've been having cold showers every morning, and allowing myself to shiver, and I feel great. If it gets uncomfortably cold I just put on more clothes. Sometime I use an electric blanket at night, which uses a fraction of the energy of an electric heater or central heating. The shivering helps to burn fat, and stimulate the production of healthy brown fat which has been implicated in many beneficial health outcomes such as better insulin response, bone density, and longevity: https://en.wikipedia.org/wiki/Brown_adipose_tissue

A bit of context on where you are would help.

Here in the upper Midwest in the US, not having your heat running during the coldest winter days (-40 wind chills) means your plumbing would freeze and pipes burst in a day or two, less if it is an older house.

I'm in the south east of the UK, but the point I'm making applies almost anywhere in the Western world; it's perfectly possible, and even healthier, to get by at a much lower indoor temperature than most people are accustomed to.

No, your point doesn't apply to anywhere in "the Western world". It depends on local weather, if there is wind or not, the amount of humidity, what kind of isolation your house has, but one of the most important is how many hours of daylight there are during the winter where you live.

We used to have a guy in my country who was telling us to wear a warmer coat during the winter to compensate for the complete lack of heat. He's no longer with as after 25 December 1989, but people still regret him.

OK, there are many places where extra clothing isn't enough, but I think most people are accustomed to an indoor temperature far higher than is necessary or healthy. It feels comfortable, but then so does morphine. Whether it's -40 or +5 degrees centrigrade outside if the temperature inside is kept at 21, reducing it to 10 will have the same effect on the people (and water pipes) living inside. Elderly & ill people need higher temperatures than the rest of us though.

My hands get cold at 18,5 C, I tried to set it lower but I'm really not comfortable. I used fingerless gloves to work with the keyboard and this helped me to go a bit lower, maybe 17,5 but it's not ideal. When I'm moving it can be colder and when I'm in bed or sofa I use a blanket or anything so it can also be lower, but for using the PC I really need 18,5 C.

If we're reducing room heat to the point that it generally harms productivity, that doesn't seem like a net gain in the system. At that point it seems far more useful to consider things like better insulation and building design standards that it does what the thermostat is set to.

Either that or like you.. I'm going to need a heated desk, keyboard and mouse.

> Lower your temperature by 1 degree right now

Not wishing to open a(nother) can of HN-worms, but what happens if you share your home with members of the opposite sex?

My wife and my daughter are the two members of the household who complain about feeling cold. In the winter they each want a hot water bottle to take to bed.

My sons and I just don't seem to mind .. and all the bedrooms are at the same temperature!

If they aren't to be convinced of the cause then there's no choice right? Then your bedroom will just be colder than theirs, and shared spaces could meet in the middle (sofa can have blankets; at dinner there is hot food; at lunch you might need to heat the eating room a bit more).

And it depends on how extreme you want to go: 13°C is laudable but I'm trying to do the same and 16-17°C is the limit before I need to put on a real winter coat and actually impair comfort/mobility while working on my computer. And that's with headwear and everything (which I take off for customer video calls, to come across a bit more professionally...). If you'd want to go 13°C then I guess shared spaces might be more towards the comfort side of the spectrum.

> If they aren't to be convinced of the cause then there's no choice right? Then your bedroom will just be colder than theirs [..]

Not wishing to be completely silly, but you've obviously not met my wife and daughter. You are correct in one sense, there is no choice: the [whole] house will be warm.

At a slightly less silly level: I'm not sure we win the climate debate by picking fights within our immediate families.

Yeah, if it's a contentious issue then it's not really a win. For me it's easier with just one other person who works in another (toasty) room.

> but what happens if you share your home with members of the opposite sex?

No reason to bring sex into it. My girlfriend complains that our home is too warm meanwhile I sit under a blanket with a hot water bottle.


New study reveals the evolutionary reason why women feel colder than men https://phys.org/news/2021-10-reveals-evolutionary-women-col...

Buy them nice sweaters :-)

Be on the lookout for moisture and mold. I tried to isolate my basement from being heated last winter, and my reward was that everything stored there got moldy. You need to maintain a temperature warm enough to reduce relative humidity, or run a dehumidifier.

That’s pretty incredible - I could never get used to 55F indoors other than when I’m sleeping.

been spending last summer in high altitude. firing up the gas heater was really expensive and fire not always practical. During days I got used to wearing functional clothing to keep me dry, a wooly hat, a warm soup for lunch. It was weird initially but got used to it fast. I even liked it after a while since I learned to really appreciate the act of making the place warm for 3-4 hours every evening, take a shot shower, cook etc ... Not something I previously considered I'd derive pleasure from as I'd always taken this for granted.

What is high altitude for you?

not that high 2200m-2600m. But temperature wise it was tough ... woke up to snow on regular basis in August. the surrounding peaks were all +4000m / glaciers. weather could be 4 seasons in a single day.

It's 12C/54F in my apartment right now, and while I'm very much in favor of people lowering their temps as much as they can, I wouldn't expect most people to put up with it. This is around the temperature that my knuckles get stiff.

That's nuts, we're at 70F most of the time and like 65F when sleeping.

I think it's quite silly to turn off nuclear power plants, rely on Russian gas, and sit in the cold when we could simply not do that.

Out of interest, how many nuclear power plants were turned off in Europe (net of replacements) since Russia invaded Ukraine?

For context[0], in 2013 (the year before Russia seized Crimea), Germany generated about 100 TWh of electricity from nuclear energy, and last year it was about 70 TWh. In that time, renewables have nearly doubled, from about 150 TWh to 240 TWh.

Of course, annualised figures don't account for the fact that there is less solar potential (and more heating demand) in the winter, but if the cost of importing non-Russian gas is cheaper than the cost of replacing ageing nuclear power stations or extending their design life, then the only concern is how much you are slowing down the race to net zero.

[0] https://www.cleanenergywire.org/sites/default/files/styles/g...

There is no not Russian gas. Germany hasn’t got the capacity to import enough liquified gas using ships. It’s going to take years to build enough terminals and it’s unlikely to ever be cheaper than buying Russian gas (I don’t think it’s in Russia’s interest to hike their prices too much (longterm) since that would make it easier to replace them).

Not true. Norway currently supplies around 25% of the EUs gas supply, with quite a lot going through a terminal in Germany.

Norway supplies gas to Germany by pipeline, see the map [1].

Germany doesn't have an LNG import terminal:

"The current large-scale LNG receiving countries in Europe are Belgium (one terminal), France (four terminals), Greece (one terminal), Italy (three terminals), Lithuania (one terminal), Malta (one terminal), the Netherlands (one terminal), Poland (one terminal), Portugal (one terminal), Spain (seven terminals – six operational), Turkey (four terminals) and the UK (three terminals). Collectively, their overall LNG capacity is 237 billion cubic metres (of gas) (bcm), which is sufficient to cover approximately 40% of Europe’s gas demand. Russia also has an LNG regasification terminal which is supplied entirely by Russian gas." [2]

[1] https://www.norskpetroleum.no/en/production-and-exports/the-...

[2] https://www.natlawreview.com/article/lng-europe-2021-current...

> In 2019, almost two thirds of the extra-EU's crude oil imports came from Russia (27 %), Iraq (9 %), Nigeria and Saudi Arabia (both 8 %) and Kazakhstan and Norway (both 7 %). A similar analysis shows that almost three quarters of the EU's imports of natural gas came from Russia (41 %), Norway (16 %), Algeria (8 %) and Qatar (5 %), while over three quarters of solid fuel (mostly coal) imports originated from Russia (47 %), the United States (18 %) and Australia (14 %).


Excellent, looks like we can stop importing coal from them as well, a double win.

As a data point, Italy turned off all its 4 (four) nuclear power plants following to a referendum in the late 80s, after Chernobyl.

> 4 (four)

I mostly see this type of writing in formal settings like contracts, or in cheques I think it's also done (but I've never seen a cheque so not sure). Now I have a chance to ask! Why do you write the same number twice? I always assumed it was to make reading easier with large numbers (not having to count groups of zeroes) or prevent writing errors (in formal contracts), but this is not a large number and HN has an edit system.

To make sure nobody thinks it's a typo.

Not OP, but I'd write it like that for rhetorical effect. It becomes even more dramatic if written as "4 (four!)".

The point is why not be more energy independent with domestic nuclear rather than increasing dependence on gas from Russia (or anyone else)?

How do I drive my gas boiler with nuclear power?

You don't have too

If nuclear is still working, demand for gas will be much lower hence lowering the dependency on Russia

(and while Russia is the biggest source, there's alternatives, and more will come up due to the conflict)

If my calculations are correct, only ~21% of gas used in europe is used for electricity, so halving the dependency. If combined power and heat plants can't be shut down (because they can't be replaced that based and still need to produce heat), this results in 12.6% of gas used only in electricity only power plants. The latter isn't really that useful.

Source for all numbers: https://ec.europa.eu/eurostat/cache/sankey/energy/sankey.htm...

16.03e6 TJ gas total

2.03e6 TJ used for electricity only

2.30e6 TJ used for electricity & heat, 60% of resulting (usable) energy is electricity

-> 1.37TJ

-> 3.40TJ of gas used for electricity, around 21%

As far as I know France uses mostly electrical heating and most of that is powered by nuclear.

Had other industrial nations acted like France in the 70s our problems, health wise, climate change wise and geopolitical would be about 1000x better.

France uses a lot more electrical heating than neighbouring countries, but gas (35%) and oil (10%) combined are more than their electrical heating (41%). Shutting of a large part of gas supplies would still be a problem. https://www.statista.com/statistics/1086485/types-heater-hou...

Two things:

- Less uranium is being produced than being consumed.

- The Russian sphere of influence is responsible for most uranium exports by far.


- Raise tsunami or hire incredibly incompetent operators to create nuclear reactor incident

- Wait for reactor containment vessel to crack open

- Collect hydrogen produced from hydrolysis and send it down the gas pipes

I think the sarcasm was unnecessary

It's not about the sarcasm, it's about the engineering challenge.

With the gas you save from not needing to use it to run your fridge and other appliances.

you get it replaced with an electric heat pump tied in to ground heat-mass.

I've not researched this - only read reports on the MSM - that installing an electric heat pump in the UK is thousands of pounds.

If that's true then it's completely unrealistic for heat pumps to become mainstream anytime soon.

We need to find alternative sources of natural gas, fast. Fracking may be a good choice at this point in time.

I really hope there will be a wave of innovation in this area. The heat pump offerings are really slim pickings in the US as well.

My idea is that augmenting with heat pumps is the most sensible step for most people. Such a system might provide a portion of the heat, and could be used for smaller heat zones (eg, some downstairs living room and/or bedroom) rather than the whole building.

My thought is that the advantage for augmenting is that it makes the geothermal setup much more affordable. You'll not end up needing to go super deep, or to install sophisticated insulation barriers.

That way, your geothermal setup can be pretty primitive.

The UK government is just about to subsidize it by thousands of pounds:

"Households in England and Wales to be offered new £5,000 Government grant from April 2022 to help replace gas boilers with heat pumps."

Which is a long term win, as they won't need to import as much fossil fuels, and it helps meet climate targets. Any impact on Putin is merely a bonus.

And what are the odds this will be done before next winter?

What are the odds that enough nuclear plants for this will be opened before next winter. Maybe if 0% of imported gas was used for electricity generation non Russian sources would be sufficient for heating (just guessing)

No. Russia supplies around 47% of imported gas, around 41% of total gas. Shutting down only electricity power plants reduces gas usage by 12%. Not using it for electricity reduces it ~21% (going to be hard, because of combined electricity & heat plants). (see https://news.ycombinator.com/item?id=30480589, all numbers for EU)

You'd have to purchase an electric one

You need a source of slow neutrons...

You are asking the wrong question. While you could save fuel that way, far more can be saved by insulation and turing temperatures to where you feel comfortable, and the with better insulation you don't have to suffer message is a winner with people who in abstract agree with saving fuel until it hurts them.

The real question then is how can you insulate every place in your country better.

The above is a complex question. There is the supply chain of insulation, contractors to do the work, and how to pay for it all. Still it is worth looking at.

I think the OP is asking in the context of losing access to or intentionally not buying Russian gas.

So the question should be framed in the context of the timeframe being days not months. If you want to significantly reduce energy consumption instantly, turning the thermostat down is incredibly effective while you work on longer timescale things like insulation and alternate heating sources.

I was thinking exactly this.

How efficient are inverter ACs for heating if it's >0 outside ? Anyone has cost comparison that would ballpark it ?

There is a great (German) database with heat pump performance. You can switch to English on the right top: https://www.waermepumpen-verbrauchsdatenbank.de/index.php?bu...

There's quite some monthly data on Air/Water systems (extracting heat from outside air, into a central heating system). I suppose good Air/Air systems could be similar. Indeed above >0, or at least >5C it would be beneficial (even more so if you also have PV installed)

Depends, some do a lot better than others, but in general until it is below freezing by a bit heat pumps are overall more efficient.

The question is about what can be done immediately. Insulating existing buildings is a long term project; in fact it is something that the UK has been failing to do over the last several decades. But reducing average household temperatures can be done overnight and in fact we have done it in the UK before in the energy crises of the 1970's when people were urged to turn the heating down to 68°F (20°C) and commercial operations were reduced to three days of operation per week.

"a bit of all" can be done immediately. A bit improved isolation, solar panels, wind farms, more working from home (to reduce travel), it all adds up.

Insulation is irrelevant to the question given the context of Russia stopping gas deliveries to Europe due to SWIFT sanctions. There simply isn't time to insulate enough houses to make a difference. It would take years.

Why give up? Individuals can act locally to make their situation more resilient.

Where did I suggest giving up?

One person who upgrades their insulation can make the equivalent difference of several turning the heat down, and when they tell their friends what their new bills are inspire more to upgrade

My point is that that is irrelevant to the issue of gas shortages in Europe due to the Ukraine situation. I'm not saying that insulation is a bad thing long term.

It was (probably) originally my question [1] in another discussion. I turned my heating down yesterday, and will fiddle with it more on Sunday evening to make sure it fits my at-home/out pattern -- it needs adjusting since I've recently stopped working from home.

We should look at insulation (for example, last year there were big protests in Britain pushing for this[2]), but it will take months or years to complete changes. Turning down the heating can be done in seconds.

[1] https://news.ycombinator.com/item?id=30479093

[2] https://www.theguardian.com/environment/insulate-britain

Save even more by working remotely from Lisbon through the winter! I haven't used a single heat source besides my electric blanket (approx. 500 Watt-hour/day) all year. And my house has poor insulation and bad sun exposure to boot. I spent the whole afternoon at the beach last Wednesday, it was so warm outside.

The only risk is you might not want to go back home for spring.

Where do you live if it's not winter? Do you rent out your place?

Still Lisbon :) This is a poorly-hidden advertisement for my home town. That said I know plenty of people renting their flats in London, Amsterdam etc for a few months while they soak up the sun here.

Very condescending advice. Refrain from giving more in the future.

I'm sure you're a hoot at parties but I'll spell it out for you if I have to: It's a tongue-in-cheek suggestion on a lazy saturday.

how's tech in Lisbon right now?

I'm not really involved in Lisbon's tech environment but from what I can see around me it's still a lot more lucrative to live in Lisbon but do your work for a market abroad. Top .5% salaries here wouldn't buy half an intern in San Francisco. As far as community goes... You'll meet people to have a drink with but that's mostly it.

In Australia, the state of Victoria in particular, most houses are not heated outside of the 'lounge room' which is not itself generally heated overnight. In the winter months it routinely gets down to or below 0C. Energy is expensive and many houses are not sealed properly.

As such, Australians tend to wear more clothing indoors during the winter months, including hats and sometimes even gloves. Electric blankets and hot water bottles tend to be used in bedrooms. Doors between rooms are kept closed, and only rooms that have people in them are heated, and only while people are in them.

So yes, if people in the EU were willing to accept living like this in the winter, they could save a lot of energy. Similarly, in the summer, most Australian houses only cool a single room, and even at that set the AC to around 27 degrees. If people in the EU lived like Australians, they could most likely survive without Russian gas.

This honestly sounds like a dreadful way to live.

It reaches 0C inside?

It seems unlikely to get that cold indoors (unless the windows are left open?!) when the record low for Melbourne is only -3°C.


people were dying in Texas last year because their houses went down to 3-4C indoors.

Better insulation alone would solve this problem and then some. I live in London which is not particularly cold, but I haven't turned on my heating in years now. My building is about 15 years old and insulated to more recent standards. There are plenty of other people who live in older houses that unfortunately are not energy efficient at all, so they have to regularly use the heating.

There's a joke in Sweden about English housing, and it goes like this:

"Hey, do you know why the English run their water pipes on the outside of their houses?"


"It's so that they can get to them easier when they freeze!"

And then everyone laughs.

...and then years later you visit England, find out that it's actually true, and then you cry.

It's pretty eye-opening how terrible the insulation standards are outside the Nordics. It's one of those things we take for absolutely granted, and then you realize that absolutely no-one else really does this.

This video made the rounds a couple of years ago:


Everyone from the Nordics commenting on it went "aawwww, how cute!", everyone else went "OMG THE HEATING BILL!!??!??!"

No, look at how the snow is piled up against the windows without melting. Those are quadruple-paned insulated panoramic windows. They do not leak heat.

with insulated houses like this the heat from humans is a problem when having family over.

The Nordics have crazy high standards for insulation. We've reached the point where increasing the standards no longer makes sense.

Spot on.. also many Nordic cities also have district heating, which can utilize surplus heat from power production.

Right, my Stockholm apartment was built in the 90's, so it's not exactly super-modern, but it still has triple-glaze windows, very well-insulated outer walls, and is connected to Stockholm's district heating system, which generates heat by burning trash. The whole building uses a trickle of heat, and my tiled bathroom is still nice and warm, and I can get scalding hot water from the taps if I want it.

There are literally zero drawbacks to the way it's constructed and heated, no compromise needed, so this HN Ask is so weird to me, and it's clear that me and OP live in completely different worlds.

Connecting district heating is not a good investment anymore (unless it's a building with 20+ flats and you want to save space in the apartments)

Triple glazed windows, 25+cm insulation, heat pump + heat recuperation, solar panels and you have a passive home. No need for gas which is a fire hazard.

Hmm, heat pumps are certainly attractive..

But if you're building a new house, wouldn't you roll in district heating if readily available.

Agreed, patching district heating into an old house might be hard/expensive.

Depends on the costs. In my location is too expensive for a single house (it cost more that a heap pump with aircon and recuperation)

There is also risk for the future. What if there is some corruption and private entity would take over trying to squeeze money from the people cause it's a monopoly?

District heating is heavily regulated here..

I think owned by the consumers.

Indeed local regulation for the lot of land I'm on stipulates that district heating must be the primary heat source.

This gives it some economies of scale, I'm guessing...

But I do wonder if geothermal power will come along to make district heating cheap and renewable.

https://dro.pm/b.mp4/preview for those not wanting to use facebook (link valid for 18 hours)

Get an electrically heated jacket / blanket. Use 20W of power (per person) instead of >2000W of power heating the whole house. Two order of magnitude reduction in heating costs and you can quit gas entirely.

To be honest I think this is the only way people in the UK are going to survive this year with energy costs literally doubling. Half the population can barely afford energy as it is.

This actually great advice. There's always been the idea that we should heat people, not places. With improvements to battery technology I'm going to have to investigate heated clothing. Any recommendations?

To complete the economic picture, it would also be helpful to know how much gas Europe imports from Russia every year, and how much more expensive it would be to buy that same amount of gas from other suppliers.

For example, if other sources of gas are twice as expensive, then Europe might want to import half as much from alternative suppliers as it does from Russia currently. If, on the other hand, other sources are only 10% more expensive, then reducing consumption by about 10% would produce an economically neutral result. (The only difference would be that people would have X amount less thermal energy, and would be Y degrees colder on average as a result).

There's also the problem of logistics. We have one (technically two) full pipelines for gas to Russia; even if we want to switch and buy all our gas elsewhere, it will be really hard to actually get it here.

There are LNG terminals in Italy, France, Belgium, Netherlands and LNG import have increased to balanced the natural gas supplied from Russia. The article below shows that at the beginning of 2022 the European gas import from Russia were 39 % down against beginning of 2021.


We have more than that, 12 according to Wikipedia: https://en.wikipedia.org/wiki/Russia_in_the_European_energy_...

3c doesn't sound like much, but reducing from 20c to 17c would be the different between comfortable and miserable.

At 21°C I can work normally at home (21.5°C to 25°C means absolute comfort to me), sitting behind a desk. At 20°C I am uncomfortable. Extra clothing doesn't help: anything beyond the thick jumper and fluffy slippers annoys me just as much as the lower temperature. I usually have to stop and take a hot shower in the middle of the day to get back to some semblance of comfort (not really conserving energy there then). At 19°C and lower I am miserable. Something to do with being tall and slim I guess. In summer heat my range of comfortable temperatures lies a few degrees higher too, so that evens out.

19°C is fine if I'm remodelling, hoovering, doing the dishes, or anything else that involves not sitting behind a desk, and I don't mind being out in freezing cold as long as I'm moving and have very, very good gloves on, but working behind a desk with my brain requires my body to be comfortable, relaxed, and not annoyed by stiff fingers hitting the wrong keys.

When the gas prices went up a few months ago I decided to turn off the heating in my apartment completely and see how far I could get. In the beginning it was about 16-17C which felt unpleasant, but by the time the indoor temp dropped to 12-13C a few weeks later, my metabolism had adjusted and it felt quite comfortable.

Great! My body doesn't adjust to that. It's only a minor hindrance in the grand scheme of things, but it sometimes does annoy me (and others whose comfort zone starts at a slightly higher temperature than the majority) when people think the problem is purely one of lack of acclimatization or grit.

I can adjust to higher temperatures just fine, but not sitting still (even with regular active breaks) at anything below 21°C. Our company used to rent office space when we were a startup in a place that didn't turn on the heating until temperatures outside dropped below a certain threshold. Sometimes this meant 19°C or 20°C for weeks: I don't get used to it; it just stops me being productive (and nice).

> when people think the problem is purely one of lack of acclimatization or grit.

In most situations, I feel like people talking extensively about grit assume the difficulty level is the same for everyone. And they tend to be antagonistic towards people who try to explain why some things are more difficult and instead double down on pushing grit.

I'm much the same. Coworkers and roommates tell me to add layers and drink tea, but layers and hot tea make no difference if it's consistently 20ºC or below. My brain just does not work for anything more demanding than deleting junk mail. Thank goodness for space heaters.

> At 20°C I am uncomfortable. Extra clothing doesn't help [...] I usually have to stop and take a hot shower in the middle of the day to get back to some semblance of comfort

I wonder how many people feel that way. I've never heard of anyone having to take a hot shower to keep warm in a 20°C room no matter the clothing. I wonder if it's just a taboo, something that simply doesn't come up, or if this happens to one in a thousand.

As for tall and slim, I'm also Dutch so I imagine I'd have heard of this more than zero times before if that were the main cause.

"Miserable" is a bit too much no? An extra layer of light clothing or getting up a doing a few steps will more than compensate for that.

I personally thing that "huge" sacrifice is feasible specially when the comfortableness is directly related to democratic countries being invaded on what is just the first step of something even much more sinister.

'"Miserable" is a bit too much no?'


No. 17°C is ridiculously cold. Do you suggest wearing gloves as well? Room temp in the winter is 23-25°C.

17 degrees might _feel_ cold, but it's definitely not cold at a level that's problematic to the human body. If it's a choice between wearing your coat inside or Russia taking over Ukraine, I think we should seriously opt for the former.

No. 25c is ridiculously hot. Do you suggest I drape a wet rag over my forehead as well? Room temp above 20c borders on criminal.

Yeah, this is the right place to fight about who has better tolerance for either extremes of heat without recognizing that people grow up in and adapt to very different climates.

That was my point.

My apologies. Point taken

My apartment gets to 17C all the time, I live in SF and never use heating. I do wear a sweater or hoodie during the day and use a thick comforter at night, but it's not bad (the cold air temp actually is really good for my sleep). You do need to make sure not to drink large amounts of cold liquid at once though.

I could see someone living their whole life in a tropical climate not being able to tolerate these temps, but in almost all of Europe this is a normal outdoor temperature. In the parts of Europe that actually get cold enough to need active heating, it's nothing. You would get used to it pretty quickly.

As a Canuck, who lives where June is 17C, and doesn't wear anything but a tshirt and pants, and often shorts at 17C, this gloves comment amuses me.

Gloves get worn at maybe -5C, -10C. Maybe.

As a Canadian myself, 17°C would be very cold for an indoor space. The standard recommendations (for offices at least) are much higher than that.

> Canadian Standards Association (CSA) and ASHRAE standards are used for thermal comfort and ventilation in indoor offices [....] These standards are a good resource to use when considering the thermal conditions in indoor office space.

> According to CSA standards Z1004-12 – Work place Ergonomics – the comfort level at work is determined by temperature, humidity, wind and work-rest cycle. The optimal temperature range for office comfort should be 23 to 26 °C with 50% relative humidity in summers and 20 to 23.5°C at 50% relative humidity in winter.


No Scotsman be you!

(Also, at best "cool', not 'very cold'. Let's have proper scaling here.)

17 is a bit on the chilly side indoors, but 23-25 in the winter (sweater season) sounds like a sweaty, awful, and, even before current events, expensive time.

21 is cozy, 20 is absolutely fine, 19 during the day is where we’re at now because toddler (who seems to be adapting better than me). We’ve been 18 at night for years - a big ol’ down comforter from my in-laws makes that ideal.

17 is perfectly ok. Just wear thermal underwear and a sweater.

Can confirm. My wife doesn't mind it at 17c ... I need it at least to be 20c, preferably 21/22c.

We're talking to our lawyers.

Back when we used to have offices rather than WFH, we eventually had employees sit in different rooms by their preferred room temperature rather than any practical function. There was so much silly behavior over the matter that was resolved by this (like people insisting on wearing coats and blankets in a 20C room because it was "freezing").

That's really amusing. Did it have any positive effect (aside from solving the AC control war). Wondering if it improved cross pollination of ideas between teams.

Not really. The company was reasonably small at the time (about 10 people) and most work done in the cloud anyway, so resolving the temperature dispute was the biggest win.

Many people fail to asses heat leakage. Often houses are badly sealed - think of a balloon - blow it like a flat tire, and spray it with soapy water and look for bubbles. Older houses are full of leaks, especially around foundation, corners of walls, windows and attic. These are often long linear seams that were never well sealed. If you take them as areas and sum them up. many old houses have a 1-3 square foot hole(equivalent) that vents upwards. Out at the top goes all the air you paid to heat and in at the bottom comes cold air, add $$ to heat. There are people with FLIR cameras. A pack of ideas here. https://www.google.com/search?q=FLIR+heat+leak&rlz=1C1CHBF_e...

Sadly there are a lot of scammers out there, but the cost has dropped a lot, so many people/groups could buy one, or rent one of the costly ones for a week and test all your houses. Works best on a cold night where the heat loss shows up well and the sun does not hinder reading. There are also apps for android and ios phone that let you record data. There are also FLIR plugins etc via Aliexpress etc.


At some of the larger (LA, SF etc) swapmeets there are importers who sell them, so you can look-see in advance

A mildly wider change would be to look up all the things that your local equivalent of the energy saving trust recommends:


They usually recommend turning down the thermostat in rooms you aren't using, and setting a timer to fit your schedule but there's a bunch of low hanging fruit that will make your home cosier, save you money, help save the planet and annoy fossil fuel oligarchs, all without any cost to yourself except using this media coverage to spur you into action.

One that they might not list, but which is interestingly geeky and so might appeal to HN, is short term rental of infra red camera to find where homes are leaking heat (best done during cold weather).

IMVHO you can't get other answer than: try it an measure...

Energy consumption does not depend ONLY by the target temp but ALSO by the external temp, or the Δt between them, the level of insulation of your house, how airtight (and eventually with what kind of VMC you have) etc even approximated answers can't be much meaningful.

What I can testify having switched from a "classic" (low insulation, no good vent etc) home to a new "class A" (french BBC to be more precise) one is that insulation, ventilation, good passive heating (windows on south, well exposed to the low winter Sun, but covered for the high summer Sun) does work enormously well. Or, the "Green New Deal" do have some tangible basis, unfortunately it's not much practical in most of the EU, at least in cities and in general in dense area, to rebuild anything accordingly, especially in a short term.

If you want to save money and have a better life, my real suggestion is: flee the city, looking for a home you can afford, one in a reasonably served place and do your best to telework. You like it or not that's the direction we heading, so the better you can get in this direction the batter you'll get paid off in the future... Other "emergency gimmick" do not really work, if they it's too little for too much effort, or they are simple raw cuts like "to save money do not go on holidays" witch might work in some short term terms, but are not much sustainable in the long run...

I heat my home at 17.5c and it's quite comfortable, even for programming, if you have good clothes.

Indeed, clothing is key here. And you need to start off warm: most people probably know the situation of warm socks and shoes not helping for already-cold feet.

- Before having to pay my own energy bill and, honestly, actually being aware at all that this is a choice, I would sit in a t-shirt and just heat up my bedroom to (presumably, I didn't measure back then) 23°C.

- With a cardigan* over the t-shirt, 21°C is just fine as well.

- Add one thin layer of long underpants and put up the hood of your cardigan and 19°C is fine as well.

- Second cardigan (I have a big comfy one that nicely fits over others) makes 17°C be on the low side but still warm enough.

- To go 16°C or lower, I need to add clothing that starts to impair mobility, like a jacket/coat meant for outside. Arms are fine; but fingers, legs, and feet get cold within two hours. This is a bit too extreme for me.

To-dos / failed things:

- I need to look into thicker pants meant to keep heat in rather than just look stylish (jeans) or act as underwear.

- For hands, I've tried fingerless gloves for typing reasons but I couldn't get used to it (it kept impairing my typing) and I ditched that idea again.

- A radiant heat source like infrared lamp is also a thing I'm considering, but I'd have to position it somehow to heat my hands and the one my girlfriend got has a very bright red color (and I'd want to check what the effect of that level/strength IR is on my eyes).

- A heated mouse helps (over longer periods of time it's noticeable, even at just 2.5W USB) but only for one hand, so it's not really a solution. Heated keyboard seems harder to make and has a lot of surface where heat gets lost.

- Intermittent movement, like 5 minutes of treadmill every hour is something I'm considering. Might also help towards exercise in general, since my current exercise scheme is nonexistent, but I wonder if that would add up to be enough or if it needs to be 30 minutes of continuous movement before it's in the realm of reasonably enough to stay healthy.

* Not a native speaker: I had not heard the word cardigan before. As wikipedia says on the sweater page: nomenclature can be quite confusing. What I mean is something thicker than a blouse but thinner than an outdoors jacket, with sleeves (long enough to cover your wrists), a zipper that can be closed, and often but not necessarily a hood. Hope I got the right word.

Any incandescent bulb aimed at your head will help you feel warmer, even a 60-75W. I tested this with a 75W halogen to make sure it wasn't necessary to use higher wattage.

Also in lieu of heated keyboard and mouse, a laptop that is doing something energy intensive will put out 100-200W; some through the keyboard, but also to the nearby areas of the desk. I know it's not ideal for how a lot of people work, but i've gotten used to it. I also use a trackball instead of a mouse so i can just put the trackball near the laptop exhaust and keep it warm too.

According to ADEME, you can save around 7% energy per °C

I don't want CTS and IIUC cold hands are bad. I can bundle up my body but my fingers have to be out for working which means cold is NG

One thing I have found is of course heat rises. I put a fan on the floor pointed at 45 degrees toward the ceiling and suddenly my place is warm with the same heating settings. I've done this at the last 4 places I've lived and the difference is striking. One place even used those high wall mounted air-conditioning + heater that blow the air out but it wasn't enough without the extra fan for circulation.

If you want to save energy, insulate or move somewhere warmer

I live in the south of France (in an apartment) and use no heating or air conditioning all year long (as well as no hot water, no fridge/freezer), no need for me, it saves money, and pretty good for the planet

How do you live without a fridge?

Where do you put all your cheese? :)

The French seem to have a somewhat different view of cheese than we (Americans) do - it’s a living thing, and why would you put a living thing in the fridge?

Related: eggs are stored and sold at room temperature in Germany. The first time I saw that kind of display, I thought some grocery manager had lost their mind. No, perfectly normal, and safe enough. Watch the refrigerate by dates on the carton.

In the US eggs are washed prior to being packaged for sale, so they must be refrigerated. Elsewhere (and in the US with yard eggs/local eggs) i guess you wash before use? I wash yard eggs because they were on the ground.

I rinse the ones that I see stuff on, but otherwise don’t worry about it.

But I still refrigerate them immediately after getting them home even if I think I’m going to use them quickly, because some habits are impossible to break.

I put them in the fridge because then I know where to always find them :)

Get it fresh from the market, consume immediately?

yea, and one side of the apartement is exposed North, so I can put vegetables/fruits there

But yes if I want some fish, I'll buy and consume right after

Usually the warmest regions in France still get minus temperature during winter, I call bullshit on this.

It's pretty serious, currently it's 6-12°C (outside) and that's the coldest of the year. I got used to the (relative) cold, inside or outside

People have difference tolerance and comfort levels, some genetic and some health related. We all know people who walk around in a t-shirt in 0 degree C weather, and others who chill easily. Still others who start to feel unwell in temperatures above 30 C, while others thrive.

Any one-size-fits-all policy that makes a quarter or whatever of the population uncomfortable, is a non-starter.

Theoretically we wouldn't save much. Given a home with good insulation it shouldn't take much more energy a few more degrees. Obviously it depends on the outside temperature.

Since the OP fixed their post to include units, 3ºC seems like a lot depending on where one's starting off.

E.g. we keep our house at ~15ºC. So 12ºC / 54ºF would be really pushing it.

Surely you realize this was posed to people who actually heat their homes? :)

Agree if you keep your house at 15C, but some people keep their houses as warm as 24C!

Wow, don't you find 15C a bit cold?

We have the AC set 21 because of the wife. I think it should be 19 or even off. It's been 10-15 degrees for a while during the day.

Apart from the reductions in energy bills & carbon emissions, there would also be a general improvement in health. Central heating has been implicated in the diabetes epidemic that plagues Western socieities: https://www.diabetes.co.uk/news/2017/apr/cooler-temperatures...

We have stopped heating by gas for the time being and switched to infrared heating in one place of the apartment.

How happy are you with the infrared heating? I've been thinking about getting some as well

We otherwise have floor heating and which is much nicer, but infrared is for the time being ok.

I'm already at 13ºC at home and my cats hate me. I won't turn off the heating.

It arrivinh spring soon, so it's a problem until next Sept-October 2022

Also remember not to ever use AC. That is also big savings on energy.

you can save a lot of gas by wearing proper clothing. e.g. don't dress summer style in the winter... without loss of comfort it is possible to live in below 16°C

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