NCPA - National Center for Policy Analysis


February 27, 2008

For decades, conventional wisdom has held that daylight-saving time reduces energy use.  But a unique situation in Indiana provides evidence challenging that view: Springing forward may actually waste energy, says the Wall Street Journal.

According to University of California-Santa Barbara economics professor Matthew Kotchen and Ph.D. student Laura Grant, extending daylight-saving time across Indiana had negative results.  For instance:

  • Residential electricity usage increased between 1 percent and 4 percent, amounting to $8.6 million a year.
  • Social costs from increased emissions were estimated at between $1.6 million and $5.3 million per year.
  • However, possible social benefits -- enhanced public health and safety and economic growth -- were not studied.

According to Kotchen and Grant, an extra hour of daylight in the evenings may mean less electricity is spent on lights, but it also means that houses are warmer in the summer and colder during daylight-saving's cooler months.  Overall, the reduced cost of lighting in afternoons during daylight-saving time is more than offset by the higher air-conditioning costs on hot afternoons and increased heating costs on cool mornings.

A 2007 study by economists Hendrik Wolff and Ryan Kellogg of the temporary extension of daylight-saving in two Australian territories for the 2000 Summer Olympics also suggested the clock change increases energy use.

Source: Justine Lahart, "Daylight Saving Wastes Energy, Study Says," Wall Street Journal, February 27, 2008.

For text:


Browse more articles on Environment Issues