alt Hacker News> What's the average monthly leccy bill in Phoenix during the summer? $400?
The average high temperature in Phoenix in July is 106.5F (41.4C). If you are cooling to 70.0F (21.1C), that's a difference of 36.5F (20.3C).
The average January low in Berlin is 28.0F (-2.2C). If you are heating to 65.0F (18.3C), that's a difference of 37.0F (20.5C).
I feel like many people living in climates that don't require air conditioning have this view that it's fantastically inefficient and wasteful. Depending on how you are heating (e.g. if you are using a gas boiler), cooling can be significantly more efficient per degree of difference. Especially if you don't have to dehumidify the air, as in Phoenix.
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100%. And can be wonderfully done by efficient heatpumps that cover the warmer months too. Also nice correlation between hot and sunny areas which means solar can get you to net zero pretty quick. (Says man looking at his solar panels right now covered with snow.)
you cannot win this argument with the average person who lives in a chilly European country. it just does not compute.
there are whole important cultural lifeways related to opening and closing windows at proper times for efficient cooling and ventilation. these work really well — in Europe — and are treasured traditions.
getting people to accept AC is sort of like trying to convince the average American to go grocery shopping on a bicycle. some may accept the idea but only the most European influenced already.
This is such an interesting perspective that I've never thought about. Thanks!
Recently it was -7C where I lived. Even without heating, my indoor temp didn't go below 15C. In regions where cold temperatures are common, isolation and heat retaining materials are very common. Is preventing heat gain as simple as preventing heat loss?
a greenhouse can heat a space by enough to be comfortable for free, but not cool it. Windows and sunlight matter.
You’re ignoring one critical difference between these two scenarios. Humans, and all human related activities, produce heat as a waste product. It’s much easier, and consumes less additional energy, to heat an occupied space, than to cool it. Thanks to the fact that your average human produces 80W of heat just to stay alive.
So every human in your cold space is 80W fewer watts of energy you need to produce to heat the space. But in a hot space, it’s an extra 80W that needs to be removed.
Add to that all of the appliances in a home. It’s not unusual for a home to be drawing 100W of electricity just keep stuff powered on in standby, and that’s another 100W of “free” heating. All of this is before we get to big ticket items, like hobs, ovens, water heaters etc.
So cooling a living space is always more costly than heating a living space. Simply because all the waste energy created by people living in the space reduces the total heating requirement of the space, but equally increases the cooling requirement of that same space.
All of this is ignoring the fact that it’s easy to create a tiny personal heated environment around an individual (it’s called a woolly jumper). But practically impossible to create a cool individual environment around a person. So in cold spaces you don’t have to heat everything up to same temperature for the space to be perfectly liveable, but when cooling a space, you have to cool everything, regardless of if it’ll impact the comfort of the occupants.