You're right that electric showerheads provide instant heat. My comparison was based on the electric showerhead I have at home, which can't heat very much due to electrical limitations. It's definitely not the case of every installation. On the other hand, the hot water I experience when showering at the gym or in fancy hotels is extremely, extremely hot and much more comfortable on a cold day. I also see some wealthy people installing gas heaters in their homes, which is why I associated electric showerheads with a lack of options.
oh, yeah, i don't think an electric showerhead in my house would work very well at all; some dumbfuck wired it with 15-gauge wire (1.4mm diameter, safe for up to about 10 amps) and at 240 volts you need more like 40 amps to provide a comfortable shower, depending on water flow rate
the entire house is on a single anemic 25-amp circuit breaker. at a low-flow 6 liters per minute (100g/s) heating from 15° to 40° (Δ temp = 25 kelvin) at 4.2 joules/°/gram, you need 10.5 kilowatts, which is 44 amps at 240 volts. at 120 volts just forget about it
i have had a super cheap non-tankless electric shower in a couple of places i've lived in argentina, which sucked. you would fill it up with water, plug it in to start heating the water, unplug it half an hour later to stop heating the water (hopefully before it overheated), and then open the valve at the bottom to run the shower. dangerous, inconvenient, and uncomfortable
on the other hand, if you're building an apartment building in brazil or a hotel in costa rica, there's nothing stopping you from including an 80-amp circuit in every bathroom for the electric shower. it's definitely cheaper than a hot-water tank or a tankless heater, and it might be safer too, since it might allow you to avoid running gas to the room
>on the other hand, if you're building an apartment building in brazil or a hotel in costa rica, there's nothing stopping you from including an 80-amp circuit in every bathroom for the electric shower.
Do these countries not have any limit on the current in a circuit?
Over here we're not allowed more than 16A in residential use and that's over 2.5 mm^2 wires. What kind of conductors do they use in Brasil for 80A circuits?
i'm not familiar with brazilian regulations but normally 80 amps would be about 3-gauge, 26mm². you can bend it with your bare hands if you get the stranded stuff. here in argentina people are evidently a lot more lax than that, so maybe in brazil they are too, but clearly you need at least 12mm²
