Can Condoms Save Us from Climate Change?

What's the greenest technology we have? It may not be electric cars or solar panels but actually good old fashioned contraception.

According to a new report from the London School of Economics and commissioned by Optimum Population Trust (OPT), using contraception to fight climate change saves nearly five times as much money as your typical low-carbon technology. Carbon credits for condoms, anyone?

Quite logically, fewer children means less carbon emissions (and less strain on diminishing natural resources). Environmentalists concerned with population growth have been saying as much for decades (or centuries if you go back to Thomas Malthus). But the report, "Fewer Emitters, Lower Emissions, Less Cost," breaks down the numbers.

The study looks at what would happen if all the "unmet need" for family planning was addressed. "Unmet need" is defined as women who want access to contraception but don't currently have it.

"One recent estimate put this figure at 200 million," OPT reported. "U.N. data suggests that meeting unmet need for family planning would reduce unintended births by 72 percent, reducing projected world population in 2050 by half a billion, to 8.64 billion. Between 2010 and 2050, 12 billion fewer 'people-years' would be lived -- 326 billion against 338 billion under current projections."

If this doesn't sound like a lot -- here's how it actually breaks down by carbon dioxide and dollars:

"The 34 gigatons of CO2 saved in this way would cost $220 billion -- roughly $7 a ton. However, the same CO2 savings would cost over $1 trillion if low-carbon technologies were used," OPT wrote. "The $7 cost of abating a ton of CO2 using family planning compares with $24 for wind power, $51 for solar, $57-$83 for coal plants with carbon capture and storage, $92 for plug-in hybrid vehicles and $131 for electric vehicles." That's a heck of a lot of savings.

And the carbon and cost savings could be even greater. "Unmet need" considers only couples who are married, but the United Nations Population Fund points out that, "community studies suggest that between 10 and 40 percent of young, unmarried women have experienced unwanted pregnancy," so, if family planning services are able to reach those populations, we're in even better shape.

Should We Put a Cap on Kids?

The study has been causing quite a stir, especially by people who missed the main point (not that we should put a cap on kids, but that we should provide family planning to people who want it), but it's also not the first to look at the carbon footprint of having kids.

In the journal article "Reproduction and the Carbon Legacies of Individuals," Paul A. Murtaugh and Michael G. Schlax of Oregon State University wrote:

While population growth is obviously a key component of projections of carbon emissions at a global level, there has been relatively little emphasis on the environmental consequences of the reproductive choices of an individual person. Obviously, the choice to reproduce contributes to future environmental impacts. There are the immediate effects caused by each offspring over his or her lifetime, but should the offspring reproduce, additional impacts could potentially accrue over many future generations.

So, not only do we need to think about how much impact our kids would have, but also if they grow up to have children, too.

Murtaugh and Schlax found that for each child a woman has in the U.S., it adds 9,441 metric tons of carbon dioxide to her "carbon legacy." This is equivalent to the emissions from burning 972,160 gallons of gasoline.

"A person's reproductive choices must be considered along with his day-to-day activities when assessing his ultimate impact on the global environment," they wrote.