5 ms·

> Geothermal wasn’t viable on the slope and with the space we had to work with, so we switched to an air source heat pump for exchange. The bigger issue was tha

by thex10 5y ago

> Geothermal wasn’t viable on the slope and with the space we had to work with, so we switched to an air source heat pump for exchange. The bigger issue was that the energy demands for the house, which included hot water heating for the pool and hot tub, outstripped the electrical supply we could get on a rural residential build: 400A. We eventually settled on supplementing our electrical generation with propane, which we had hoped to avoid. High-efficiency electrically powered water boilers and other mechanical systems are more advanced in Europe, but we found that subcontractors were wary of importing anything unfamiliar (and unrated for North America) and prefered to use gas. Huh, as someone who wants one day to build a passive house to live in, this is all very interesting. Sounds like they're not getting quite as modern of a home as they wanted.

Aeolun 5y ago
400A?! My house can make do with 60A, and my previous one with 40A Do they use 350A to heat a swimming pool? Talk about a waste of energy.
- jakewins 5y ago
  Are you in EU? Recall North America uses 120VAC, so a 400A service is equivalent to 200A in the EU
  - danachow 5y ago
    Most residential electrical service in the US is 200A or well below that. Especially if you have a place with gas heat, hot water, dryer, range you do not need that much. But even with electric appliances and a typical pool heater, 200A is plenty. 400A service in the US is the purview of the very wealthy for their Taj Mahals - which is obviously overrepresented here - but that's a fucking distorted view point if you think it's the norm.
  - EricE 5y ago
    NA Houses still get 240 delivered to them - so yeah, 400A is huge.
  - jaclaz 5y ago
    But 200A in EU is roughly 44-50 kW, a common contract for a flat (here in Italy) is 3 kW, if you have a heat pump and/or conditioner it goes to 4.5 or 9 kW. I have seen (largish) villas with 20 or 25 kW, but everything more than that - like 100 A or so - is definitely beyond common use.
    - KptMarchewa 5y ago
      >3 kW So kettle + oven and you blow your fuses?
      - jaclaz 5y ago
        Yep, 3 KW is the "minimum contract" (but still very common for small flats) though there are of course no fuses anymore but a current limiting switch that trips and that can be re-armed, it allows peaks of about 20% more than target, older versions of these switches allowed higher peaks, so when they started replacing it with the new version which is more "strict" many contracts were upgraded to 4.5 KW because the limiter was tripping very often. Traditionally the oven was (only in the last years electic ones have become prevalent/ubiquitous) gas-powered and that electric kettles are not common, so the typical tripping scenario is now electric oven cooking+ironing or (say) iron+dishwasher+washing machine.
  - jcrawfordor 5y ago
    NA uses 120VAC at most loads - but service is 240V split. So 200A service in NA is the same as 200A in the EU. Of course this is confusing since we often talk about 120V loads, e.g. a 15A electric kettle in the US is pretty lame compared to a 15A electric kettle in the UK. The 120V outlets are approximately equally split between the two legs (which you could view as -120 to 0 and 0 to +120), so one way you could view it is that 200A service in NA allows for about 400A of 120V load. But then larger loads are usually across both legs and you have to account for imbalance so it doesn't work out quite that simply. And then there are "weird load" like dryers, which commonly put the heating element across both legs but the drum and blower motors across only one, resulting in some amps on both legs and some more amps on only one of them. And while we're at it commercial buildings often run the lighting across both legs for wire gauge economy. So there's a lot of nuance on the load side. But on the supply side it's all 240V either way (well, kind of, could be 208V in case of a wye supply, but that's not common).
- DoingIsLearning 5y ago
  When they say 'Developed' nations are the major CO2 emission contributors per capita due to their unsustainable lifestyle I think of this graph: https://ourworldindata.org/grapher/co-emissions-per-capita?tab=chart&country=CAN~USA~GBR~JPN~NZL~CHE~SWE~FRA~DNK~ISR~NLD~AUS https://ourworldindata.org/grapher/co-emissions-per-capita?t... The split is almost bi-modal, not pointing fingers but this bundling seems a little bit of an unfair generalization, not all nations pollute alike.
- hinkley 5y ago
  One space heater is 12-15 amps. I can't count how many people I've had to explain that to as they scratched their heads why they keep tripping the circuit breaker in the winter. Also lesser know fact: A circuit breaker doesn't cut off at the rated amperage. It cuts off when it spikes above that amperage. When the current is steady, you can blow past the limit, but one little wobble and it will finally trip. "I wasn't doing anything different" being a common refrain. A little ripple from the city power or the other end of the house can push it over.
  - TheCoelacanth 5y ago
    Space heaters are incredibly inefficient, though. You could almost heat the whole house with the same energy using a heat pump.
    - hinkley 5y ago
      I mean, technically they're 100% efficient (as are computers). Heat pumps are limited by how cold and humid it is outside. The coils freeze up and they have to cycle to melt it off. It's not particularly cold in Vancouver but it is definitely humid. I'm not sure where the triple point is.
      - TheCoelacanth 5y ago
        100% efficient is extremely inefficient for electric heating. A good modern air source heat pump has far above 100% efficiency in all but the coldest climates and a ground source heat pump has far above 100% efficiency in essentially any climate.

by thex10 5y ago

Aeolun 5y ago

400A?! My house can make do with 60A, and my previous one with 40A Do they use 350A to heat a swimming pool? Talk about a waste of energy.

jakewins 5y ago
Are you in EU? Recall North America uses 120VAC, so a 400A service is equivalent to 200A in the EU
- danachow 5y ago
  Most residential electrical service in the US is 200A or well below that. Especially if you have a place with gas heat, hot water, dryer, range you do not need that much. But even with electric appliances and a typical pool heater, 200A is plenty. 400A service in the US is the purview of the very wealthy for their Taj Mahals - which is obviously overrepresented here - but that's a fucking distorted view point if you think it's the norm.
- EricE 5y ago
  NA Houses still get 240 delivered to them - so yeah, 400A is huge.
- jaclaz 5y ago
  But 200A in EU is roughly 44-50 kW, a common contract for a flat (here in Italy) is 3 kW, if you have a heat pump and/or conditioner it goes to 4.5 or 9 kW. I have seen (largish) villas with 20 or 25 kW, but everything more than that - like 100 A or so - is definitely beyond common use.
  - KptMarchewa 5y ago
    >3 kW So kettle + oven and you blow your fuses?
    - jaclaz 5y ago
      Yep, 3 KW is the "minimum contract" (but still very common for small flats) though there are of course no fuses anymore but a current limiting switch that trips and that can be re-armed, it allows peaks of about 20% more than target, older versions of these switches allowed higher peaks, so when they started replacing it with the new version which is more "strict" many contracts were upgraded to 4.5 KW because the limiter was tripping very often. Traditionally the oven was (only in the last years electic ones have become prevalent/ubiquitous) gas-powered and that electric kettles are not common, so the typical tripping scenario is now electric oven cooking+ironing or (say) iron+dishwasher+washing machine.
- jcrawfordor 5y ago
  NA uses 120VAC at most loads - but service is 240V split. So 200A service in NA is the same as 200A in the EU. Of course this is confusing since we often talk about 120V loads, e.g. a 15A electric kettle in the US is pretty lame compared to a 15A electric kettle in the UK. The 120V outlets are approximately equally split between the two legs (which you could view as -120 to 0 and 0 to +120), so one way you could view it is that 200A service in NA allows for about 400A of 120V load. But then larger loads are usually across both legs and you have to account for imbalance so it doesn't work out quite that simply. And then there are "weird load" like dryers, which commonly put the heating element across both legs but the drum and blower motors across only one, resulting in some amps on both legs and some more amps on only one of them. And while we're at it commercial buildings often run the lighting across both legs for wire gauge economy. So there's a lot of nuance on the load side. But on the supply side it's all 240V either way (well, kind of, could be 208V in case of a wye supply, but that's not common).
DoingIsLearning 5y ago
When they say 'Developed' nations are the major CO2 emission contributors per capita due to their unsustainable lifestyle I think of this graph: https://ourworldindata.org/grapher/co-emissions-per-capita?tab=chart&country=CAN~USA~GBR~JPN~NZL~CHE~SWE~FRA~DNK~ISR~NLD~AUS https://ourworldindata.org/grapher/co-emissions-per-capita?t... The split is almost bi-modal, not pointing fingers but this bundling seems a little bit of an unfair generalization, not all nations pollute alike.
hinkley 5y ago
One space heater is 12-15 amps. I can't count how many people I've had to explain that to as they scratched their heads why they keep tripping the circuit breaker in the winter. Also lesser know fact: A circuit breaker doesn't cut off at the rated amperage. It cuts off when it spikes above that amperage. When the current is steady, you can blow past the limit, but one little wobble and it will finally trip. "I wasn't doing anything different" being a common refrain. A little ripple from the city power or the other end of the house can push it over.
- TheCoelacanth 5y ago
  Space heaters are incredibly inefficient, though. You could almost heat the whole house with the same energy using a heat pump.
  - hinkley 5y ago
    I mean, technically they're 100% efficient (as are computers). Heat pumps are limited by how cold and humid it is outside. The coils freeze up and they have to cycle to melt it off. It's not particularly cold in Vancouver but it is definitely humid. I'm not sure where the triple point is.
    - TheCoelacanth 5y ago
      100% efficient is extremely inefficient for electric heating. A good modern air source heat pump has far above 100% efficiency in all but the coldest climates and a ground source heat pump has far above 100% efficiency in essentially any climate.