Thats across multiple phases. Commonly used for high current appliances such as clothes dryers.

Most moderate sized homes in the US will have two phases whilst homes in NZ can suffice on a single phase. 

https://en.wikipedia.org/wiki/Mains_electricity_by_country#/media/File:World_Map_of_Mains_Voltages_and_Frequencies,_Detailed.svg

This says the US is 120V.

3 phase in New Zealand is 400v

120v phase to neutral, with two phases being supplied 180 degrees out of phase. Therefore 240v phase to phase.

Note that the house in the video has 200A service, i.e. 48kW. Compares pretty well to my houses 14kW... But in the USA, a dryer gets a 30A plug, where as in NZ, it gets a 10A plug, so their houses are typical capable of pulling a lot more power than ours.

in a 3-phase power system the phase-phase voltage is 1.73 x phase-neutral voltage

that is 230V / 398V     or  120V / 208V  or as our power was 240V / 415V

The 3 phases are 120 degree separation - hence the 1.73 factor (1.73 x 1.73 =3)

domestic are split phase 240v phase to phase, 120V phase to neutral (180 deg)

When 3 phase it 208V phase to phase (120 deg)

there are split phase supplies in NZ although very rare, 460V phase to phase

k1wi: Residential service drops are a range of capacities here. Split phase (two hots at ~120v for a nominal 240v across them) and a neutral run from the street to the house, usually from a pole mounted transformer.

240v branches require a double breaker (the phases alternate on the breaker board).

We just upgraded our drop from 100A to 200A, but there are also 60A drops around, usually older drops, and you can get 400A drops. They’re more common in the South. Even while house electric around the north east probably max out at 200A.

Same here in Western Canada.

We're in an older city suburb - built in the 60's - many houses have small, original 100A breaker boards (240V-50A stove, 30A dryer and a 1/2 dozen 120V-10A outlets)
Our power company's pushing (and subsidizing) upgrades to 200A panels, we took them up on it and they put the new board in the garage with the house fed off it as a secondary..

They've also been upgrading the pole mounted transformers in all the back alleys to cope with higher draws, so everyone can have that 50A, 240V EV charging option - and expecting the whole city to somehow move from forced-air gas furnaces to electric heat pumps over the next couple of decades (LOL!)

AESO - the province’s Electric System Operator, which manages the power grid - is predicting an increase in EV's ranging from a low estimate of 200,000 (or 10,000 new EV's yearly) to two million by 2041.. meaning an increase in peak (charging) power from low-end 400 MW to high-end 3,900 MW (!) of electricity demand. Hence all the upgrading.

Along with the new 200A supply we now have 6 different NEMA receptacles ranging from 5-15R (14-30R & 14-50R) in the house, 5-20R's and 6-20R's to 6-50R's in the garage as well as hardwired 60A Circuits.
SO many plugs and extension cords..