As the anointed resident blogger on daylight saving time, I thought I would bring to your attention a study conducted by researchers at the University of California-Santa Barbara (UCSB). The study focused on Indiana, which only two years ago began observing daylight saving time (DST) as a whole. Prior to that, only a few Indiana counties did so.
Analyzing meter readings from southern Indiana households before and after the adoption of the observance of daylight saving time, the researchers made the following conclusions:
... DST results in an overall increase in residential electricity demand. Estimates of the overall increase in consumption range from 1 to 4 percent. We also find that the effect is not constant throughout the DST period, with evidence for electricity savings in the spring and increases that are greatest in the fall. These findings are generally consistent with simulation results that point to a tradeoff between reducing demand for lighting and increasing demand for heating and cooling.
The researchers note that further research would be necessary to determine if their findings could be replicated in other parts of the country. They also don't discount the benefits DST may provide to people's sense of well-being. A preliminary, working paper on the study, titled "Does Daylight Saving Time Save Energy? Evidence from a Natural Experiment in Indiana" can be found here (PDF).
According to the Indiana Business Journal, however, Duke Energy Corp.—the company whose data the UCSB researchers used—doesn't endorse the study's conclusions. Among Duke's objections were the study's exclusion of data on electricity consumption by business and industry and the fact that most of its residential customers in the study area don't rely on electric heat.
For a summary of the study and the debate surrounding DST, the Wall Street Journal article "Daylight Saving Time Wastes Energy, Study Says" provides some good information.
Previously: "Time Changes Risky for Pedestrians"
Photo: "12:16 P.M." of a three-sided clock at the Västerhaninge, Sweden, commuter station, by Steffe.
