Stay married -- divorce is bad for environment

By Deborah Zabarenko, Environment Correspondent

WASHINGTON (Reuters) - Irked spouses looking for a reason to stay married were offered a novel rationale by U.S. researchers on Monday: divorce is bad for the environment.

The global trend toward higher divorce rates has created more households with fewer people, scientists at Michigan State University reported in the Proceedings of the National Academy of Sciences.

More households means more energy expended to build, fuel, and provide water for them, the researchers wrote.

"Globally, the number of households is increasing much faster than the number of people," said co-author Jianguo "Jack" Liu in a telephone interview.

"Even in regions with declining population, we see substantial increase in the number of households. Divorce is the main reason for reducing the number of people in a household," he said.

The average divorced person's household is about 40 to 50 percent smaller than the average married person's household, Liu said. But whether there are three or six people in a house, the amount of fuel needed to heat them is about the same.

Divorce tosses out any economies of scale, the researchers found.

In the United States, divorced households used 73 billion kilowatt-hours of electricity and 2.850 trillion litres of water in 2005 that could have been saved if households had stayed the same size as when they were married. Thirty-eight million extra rooms were needed, with associated costs for heating and lighting.