Arizona observed DST in 1967 under the Uniform Time Act because the state legislature did not enact an exemption statute that year. In March 1968 the DST exemption statute was enacted and the state of Arizona has not observed DST since 1967. This is in large part due to energy conservation: Phoenix and Tucson are among the hottest US metropolitan areas during the summer, resulting in more power usage from air conditioning units and evaporative coolers in homes and businesses. An extra hour of sunlight while people are active would cause people to run their cooling systems longer, thereby using more energy. The summer of 1967 was the one year that DST was observed. The State Senate Majority leader at the time owned drive-in theaters and was nearly bankrupted due to DST, as movies could not start until 10:00 p.m. (2200) at the height of summer, well past normal hours for most Arizona residents. There has never been any serious consideration of reversing the exemption.
Because of Hawaii’s tropical latitude, there is not a large variation in daylight length between winter and summer. Advancing the clock in Hawaii would make sunrise times close to 7:00 a.m. even in June. Most of the inhabited islands are located close to the west end of the Hawaii-Aleutian time zone, but Oahu, Kauai and Niihau are located more than 7 degrees west of the Hawaii-Aleutian time zone’s meridian and should, theoretically, be located in the next time zone to the west. (Until about 1946 Hawaiian standard time was based on longitude 157.5 deg west rather than 150 deg.)
Hawaii did experiment with DST for three weeks between April 30, 1933 and May 21, 1933; there is no known official record as to why it was implemented or discontinued. Hawaii has never observed daylight saving time under the Uniform Time Act, having opted out of the Act’s provisions in 1967.