• 6 Posts
  • 1.39K Comments
Joined 2 年前
cake
Cake day: 2023年7月9日

help-circle





  • At my local commuter rail station the entrance to the parking lot is immediately next to the track. It’s easily within margin of error for GPS and if you’re only focusing immediately in front of you the pavement at the entrance probably look similar.

    There are plenty of cues so don’t rolled shouldn’t be fooled but perhaps FSD wouldn’t pay attention to them since it’s a bit of an outlier.

    That being said, I almost got my Subaru stuck once because an ATV trail looked like the dirt road to a campsite from the GPS, and I missed any cues there may have been









  • As a European those power draws listed sound absolutely absurd to me

    Let me clarify - those are standard sized circuits, not actual draw. However the service has to be sized to handle it, and over-provisioning to account for it.a customer might install a stove that draws the full load and might use all the burners at once, and you have to account for typical usage patterns.

    For sure it’s a well earned stereotype that Americans use more electricity than many other places. We tend to have bigger houses, more and bigger appliances. We not only don’t have that base charge per size of service but too some extent are charged less to use more: essentially we subsidize people electric resistive heat, who can pay a lower usage rate. We also don’t usually have time of use metering, although some do: my rate is the same whether I charge my car at night or at peak time. And of course our current leadership is intent on rolling back the efficiency standards we have.

    Taking your heat pump dryer example, those are finally available here but tend to cost a lot more than a traditional dryer: savings on efficiency will never make back the extra purchase cost More importantly they’ve only been available in small sizes, not typical for houses, especially with families



    1. Sometimes breakers don’t trip, so there’s a small risk of fire
    2. Restarting the whole house may have large initial loads as everything starts at once: more chance of it happening again or potentially damaging some appliances
    3. Risk of heat damage to wiring with repeated trips, risk of broken connections from more frequent expansion from heat/cool cycles
    4. Inconvenience, especially in the old days when you’d have to go through to set clocks. If while asleep you might not be awoken in time. If you weren’t home, maybe food gone bad
    5. Occasional home health appliances are critical to keep going

    Realistically it comes down to how conservative you are with over-provisioning. You might also expect it to handle the load for 50 years of growing usage. In the US we have the expectation of rarely to never tripping the main and when that happens it’s more likely an electrician call



  • In my experience people get by with a 3x25A (17 kW available, matches approximately a 70A service in the US)

    Wow, how do you do that?

    Of course over-provisioning is a thing but that’s crazy. Maybe you have much smaller appliances or assume much lower usage, but 70a basically assumes 2 major appliances at a time, using close to max load, and with nothing else turned on.

    Typical 240v major appliances

    • level 2 EV charger: 50a
    • stove: 50a
    • central ac: 40a
    • dryer: 40a
    • heat pump: 50a+
    • water heater: 50a

    Of course you won’t use them all at once and they won’t usually be drawing their full rated load but I would not want to deal with being limited to one at a time so I can also turn on the lights or use the microwave

    That can theoretically draw 280a, before you even count things like lights and small appliances. If you added up all possible circuits, you may be hitting 1000a theoretical in a modern house. I’m comfortable that My 200a service will handle any combination I might use, but 70a definitely not

    By contrast I once lived in an apartment with 60a service. It did not have most of these large appliances but I frequently tripped the main with combinations like stove + window ac + microwave + lights



  • For me the smart charger was a key feature, and I never understood why that is never talked about. I have 200a service which was plenty for one fully powered charging service, but with the likelihood of electrification in upcoming years I was hesitant to have two. It was pretty clear I needed to prioritize smart charging so I’d have that possibility.

    I can also configure it to only charge my allowed vehicles, should that ever become an issue

    So far my family only has the one EV, so we only need the one charger. But I like that if we needed a second charger it could be on the same circuit and they could dynamically share the power to maximize charging