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Comment by alex_duf | Hacker News Reader

That's a crazy amount of power, for reference here in France I run my whole house on a 9kW service (9kVA to be precise). That's with a heatpump and everything electric, including an electric car, and running the heating at more than 20°C during the winter. I might move it to three phases and 12kVA when we get a proper car charger installed, but with our solar panels and smart charging I think I might be able to save myself the trouble.

How are houses in the US made to be this inefficient? That's about one quarter of your installation if I'm doing the math correctly, (110V in the US right?)

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Pool, hot tub, and uses air conditioning in Las Vegas...

Look, for better or for worse, Las Vegas is a testament to man's dominance of nature, and that takes a lot of electricity. It's not really about the efficiency.

Or as King of the Hill (TV Show) says of Phoenix: "This city should not exist. It is a monument to man's arrogance."

It's Las Vegas. Has a pool and hot tub and, of course, air conditioners. You folks in Europe don't have air conditioners and mostly don't need them (except when you do you do and you suffer). This is not really representative of most of the U.S., but it is representative of a lot of the U.S. Basically everywhere in the South we have central air conditioning, though it's not that common to have hot tubs.

The previous poster actually has an air conditioner. You Americans don't usually understand that heat pump is for heating AND cooling.

I expect it's partly efficiency too. He already said he has inefficient AC. As I understand it dryers that just vent to the atmosphere are still common in America which is insane.

I think power is cheap enough in America that you don't care about wasting it.

The house is probably gigantic.

Houses in the US tend to be pretty large to begin with[1]. In newer cities that have a lot of land to expand into (entire new subdivisions in the suburbs), the average house is around 2500 feet^2 (~230 m^2).

But houses in the US also tend to only have one AC unit for the entire house. So if a house has three AC units, it is probably even larger than average. It could be 3000-4000 ft^2 (~275-375 m^2).

And naturally it takes a lot of energy to heat and cool all that space.

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[1] https://www.propertyshark.com/Real-Estate-Reports/2016/09/08...

This is incredibly regional: in the south east ya, I guess you have lots of space and a not so great climate to deal with.

Houses on the west coast might just have heat pumps, maybe...and not even a central AC unit (instead, you get a separate heat pump unit for each room you want to heat/cool, our 2016 house has two units, but the first floor lacks any AC at all and only has small conductive heaters). Our electric bills are super low, however (mostly because...we don't need to really use heat all that much, and maybe AC a couple of weeks per year).

That was my impression as well. I'm in Poland, and 9kW is what you'd expect for an apartment or a small house. I needed 17kW for a small country house recently, but that's because of a "flow-through" water heater (no boiler tank) which makes sense in installations which aren't used every day.

A heat pump can heat/cool a small modern insulated wooden house with a 200W-450W power budget, throughout the year, with outside temperatures below freezing.

I installed an EV charger recently, with an 11kW of power allocation.

All that is way below the power in the installation mentioned…

US houses are incredibly inefficient.

I'm in Japan, and people even use less. 3-4kW is standard for a condo, 4-6kW is standard for a house, 10kW is max in general for a house with induction cooker and heat pump boiler tank.

We're not in Poland. Like I said in the post, I'm in the Nevada desert, in a 400 sq meter house, with a pool and a hot tub.

Here's a weather comparison to remind you that year-round, the highs in Krakow are lower than the LOWS in Vegas: https://weatherspark.com/compare/y/85104~2228/Comparison-of-...

I understand that. So include a 1.3x factor for cooling over heating (heat pumps are more efficient when heating than when cooling). That's still a far cry from the wattages/amperages mentioned.

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