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Family planning the cheapest way to prevent climate disaster?

A sturdy condom could be humankind’s best weapon to prevent a climate calamity, according to a cost-benefit analysis by British economists.

Contraception is almost five times cheaper than conventional green technologies as a means of combating climate change, the London School of Economics concluded after comparing all the alternatives to reducing future emissions of CO2 into the atmosphere.

The simplest solution, in other words, is to cap human population growth.

The study looks only at the economic alternatives. The organizers of the research are fully aware of the controversial nature of the suggestion that the human population growth rate needs to be slowed, which is perhaps why they point out that that every additional person, “especially each rich person” in developed countries, reduces everyone’s share of the planet’s dwindling resources even further.


Distribution of resource-rich populations, as suggested by electricity consumption at night.

Image courtesy NASA

Each U.S. $7 spent on basic family planning over the next four decades would reduce global CO2 emissions by more than a tonne (2,200 pounds), said the Optimum Population Trust (OPT), a British think tank concerned with the impact of population growth on the environment. OPT commissioned the research from the London School of Economics.

“To achieve the same result with low-carbon technologies would cost a minimum of $32,” OPT said in a statement.”The UN estimates that 40 per cent of all pregnancies worldwide are unintended.”

Fewer Emitters, Lower Emissions, Less Cost 

The report, “Fewer Emitters, Lower Emissions, Less Cost,” concludes that “considered purely as a method of reducing future CO2 emissions,” family planning is more cost-effective than leading low-carbon technologies. It says family planning should be seen as one of the primary methods of emissions reduction.

Meeting basic family planning needs along the lines suggested would save more than billion tons of CO2 between now and 2050–equivalent to nearly six times the annual emissions of the U.S. and almost 60 times the UK’s annual total, OPT said.

“It’s always been obvious that total emissions depend on the number of emitters as well as their individual emissions–the carbon tonnage can’t shoot down, as we want, while the population keeps shooting up.”

Roger Martin, chair of OPT, said the findings vindicated OPT’s stance that population growth must be included in the climate change debate. “It’s always been obvious that total emissions depend on the number of emitters as well as their individual emissions–the carbon tonnage can’t shoot down, as we want, while the population keeps shooting up,” Martin said.

“The taboo on mentioning this fact has made the whole climate change debate so far somewhat unreal. Stabilizing population levels has always been essential ecologically, and this study shows it’s economically sensible too.

“The population issue must now be added into the negotiations for the Copenhagen climate change summit in December.

“This part of the solution is so easy, and so cheap, and would bring so many other social and economic benefits, from health and education to the empowerment of women. It would also ease all the other environmental problems we face–the rapid shrinkage of soil, fresh water, forests, fisheries, wildlife and oil reserves and the looming food crisis.”

All of these problems would be easier to solve with fewer people, and ultimately impossible to solve with ever more, Martin added.

“Meanwhile each additional person, especially each rich person in the OECD countries, reduces everyone’s share of the planet’s dwindling resources even faster.

“Non-coercive population policies are urgently needed in all countries. The taboo on discussing this is no longer defensible.”


In this UN map of world contraceptive use in 2007, the scale ranges from pale yellow (less than 20 percent) to dark blue (75 percent or more).

The London School of Economics study, based on the principle that “fewer people will emit fewer tonnes of carbon dioxide,” models the consequences of meeting all “unmet need” for family planning, defined as the number of women who wish to delay or terminate childbearing but who are not using contraception, OPT said.

“One recent estimate put this figure at 200 million. UN data suggest that meeting unmet need for family planning would reduce unintended births by 72 per cent, 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.”

The 34 gigatonnes of CO2 saved in this way would cost $220 billion–roughly $7 a tonne. However, the same CO2 saving would cost over $1 trillion if low-carbon technologies were used, OPT said. “The $7 cost of abating a tonne 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.”

The study may understate the CO2 savings available because the estimates of unmet need are based on married women alone, yet some studies suggest up to 40 per cent of young unmarried women have had unwanted pregnancies, OPT added.

Said Martin, “The potential for tackling climate change by addressing population growth through better family planning, alongside the conventional approach, is clearly enormous and we shall be urging all those involved in the Copenhagen process to take it fully on board.”

What do you think about this? Should the leaders meeting in Copenhagen have a serious discussion about addressing population growth through better family planning?