Next100 - A Dialogue on the Next Century of Energy

Nov 06 2008

Electricity Wasting Time?

Getting an extra hour of sleep in the fall, thanks to Daylight Saving Time (DST), is one of life's little pleasures. Sadly, according to two UC Santa Barbara scholars, it turns out to be a guilty pleasure--one that increases energy consumption and creates more pollution.

The United States first adopted DST--starting in World Wars I and II--as a means of saving energy, not as a policy to promote agriculture as sometimes assumed. It was expanded most recently in 2007, following the Energy Policy Act of 2005. More than 1.6 billion people in 76 countries now fumble with their clocks twice a year to practice DST.

But does it achieve its goal? Past research has been scant and inconclusive. Sorting out the specific effects of DST on energy use, separate from all other factors, is like finding the proverbial needle in a haystack.

But in a new paper for the UC Energy Institute, researchers Matthew Kotchen and Laura Grant take advantage of the fact that for many years some counties in Indiana practiced DST while many others did not. In 2006, following federal law, all counties adopted DST. By comparing energy use over time between counties, with and without DST, they were able to detect the program's real impact.

It turns out that DST increases residential electricity demand, most notably in the fall. The extra bill comes to about $9 million a year for Indiana households. Pollution increases as well. Apparently, by changing the time when people are likely to be at home, any reduction in lighting is more than offset by increased demand for heating and cooling. This effect, the researchers conclude, is likely to be even worse in the southern United States due to widespread use of air conditioning.

Posted by: Jonathan Marshall | Comments (0) Permalink