Depends on the time of year.
Summer solstice = 0
Winter solstice = 24
Spring/fall equinox = 12
All other days, some gradual change from 0 to 24. This is true of any land within the Arctic or Antarctic circles (of course the times are reversed for the Arctic circle). Those circles are defined by the places on Earth that have at least one day of complete light and complete darkness during the year.
