Dec. 3, 2007 -- Environmentalists who are thinking of getting a divorce may want to reconsider, a new study at Michigan State University finds.
Households in which a divorce occurs have a greater negative impact on the environment in terms of efficient use of resources than the households of married couples, according to research that will be published this week by the Proceedings of the National Academy of Sciences.
The reason is simple — it's all about efficiency, says Jianguo Liu, lead author of the study who has the Rachel Carson chair in ecological sustainability at the university's department of fisheries and wildlife.
"In the divorced households, the number of people is smaller than in married households," Liu told ABCNEWS.com. "The resource efficiency used per person is much lower than in married households."
For example, the amount of heat used in a house is the same whether one or four people live there; the fewer people who occupy the space, the more energy is wasted.
"Whether you have four or two people, you still use the same amount of heat, and whether you have two people or 10 people, the light is on," Liu said.
Similarly, because divorced households have fewer people, they have more rooms per person and are using their living space less efficiently. This inefficiency may also lead to an increase in generating greenhouse gases, the study concludes.
To come up with their findings, Liu and postdoctoral associate Eunice Yu examined data from 12 countries, including the United States, Brazil, Ecuador, Kenya, Mexico and Spain.
In the United States, they found that divorced households spent 46 percent more per capita on electricity and 56 percent more on water than married households did.
According to the study, if divorced households could have the same resource efficiency as their married counterparts, they would need 38 million fewer rooms, use 73 billion fewer kilowatt hours of electricity and 627 billion gallons of water in 2005 alone.
Liu said he was inspired to do the study because of a global population phenomenon — a decrease in population growth but an increase in the number of households.
"The number of people in the households is getting smaller," he said. "One of the main reasons for the smaller households is divorce."
This maxim applied even in countries where divorce was not traditionally accepted, which surprised Liu.
For now, Liu hopes that his research will have an impact on couples who are considering divorce.
"[Couples] don't know the impact on environment from divorce. … After the research is done, it's really simple. Before our research, nobody knew about the impact," he said. "My hope is that they will think about the decision. Also, they can inform other people about the environmental impact of divorce."
But Raoul Felder, a prominent New York divorce attorney, is skeptical.
"I think people who want a divorce are so driven to improve their quality of life — environmental factors are the least of what they're thinking about," he said. "If they're not thinking about the effect of divorce on children, they're not going to be thinking what their environmental footprint is going to be or how many kilowatts they're using."
There is hope, however, for environmentally conscious divorcees. When those people remarry (or cohabit), the environmental tally sheet corrects itself, Liu said.