Air quality has improved dramatically in rich countries over the past century. Yet air pollution is still a huge problem, especially in the developing world. It kills about 7 million people each year, accounting for one out of every eight deaths globally. In India, it now kills 1.6 million people each year or one of six deaths. But the most deadly air pollution comes from inside people’s houses, because 2.8 billion people still use firewood, dung and coal for cooking and to keep warm, breathing polluted air inside their homes every day.
To people who don’t live under these conditions, it is hard to imagine how polluted the indoor air is. The World Health Organization says outdoor air, for instance, in Beijing, New Delhi and Karachi is several times more polluted that the outdoor air in Berlin, London and Paris. But the typical indoor air in a developing country house with an open fire is many times more polluted than Beijing, New Delhi or Karachi. That is why indoor air pollution kills 4.3 million people each year, making it one of the world’s leading causes of death.
Yet indoor air pollution is rarely among the big issues the world discusses. In 2000, the world made a number of smart, short promises for 2015 called the UN Millennium Development Goals, focusing on poverty, hunger, education and child mortality. They were mostly good promises, but indoor air pollution was missing.
Now, the world’s 193 governments are discussing what targets to set for 2030, and there is a bewildering array of 169 proposed targets. While indoor and outdoor air pollution are now part of the targets, so is everything else. And with so many promises we have no priorities.
According to a new study for the Copenhagen Consensus, the simplest solution is to replace inefficient, smoky stoves by more efficient, less smoky ones. Providing 1.4 billion people with such improved stoves would save almost 450,000 lives a year and avoid almost 2.5 billion days of illness annually.
Moreover, more efficient stoves would on average save about 30% fuel, which translates into a saving of up to $57 per household per year, and at the same time make cooking more efficient and less time consuming. In total, the health and non-health benefits are estimated at $52 billion per year.
What would it cost to make such a big improvement? In many parts of the world, an effective, improved stove costing just $30 is all that is needed to reduce indoor air pollution dramatically. The price is higher in some parts because of particular needs; in China, heating is needed as well as cooking, so the cost of an effective, improved stove increases to somewhat over $100. Nevertheless, providing improved stoves for 50% of those cooking on unhealthy, smoky, traditional ones would cost about $5 billion a year. So for every dollar spent, better stoves would do $10 worth of good. However, helping 1.4 billion people with better stoves doesn’t solve the problem. Another 1.4 billion are still cooking with traditional, polluting stoves, and even improved stoves cause more pollution than found in most cities.
Besides, some of the smoke from these improved stoves reaches outside so there is pollution within the community as well.
A much cleaner solution is to get everyone to use gas. This would save 2.3 million deaths a year and avoid 13 billion days of illness, leading to more than twice the benefits. But unfortunately, gas stoves are more expensive and gas can cost about $200 per household per year, so the costs are more than 10 times higher. Even so, for every dollar spent, we would get $2 worth of benefits, a respectable, but not nearly as good a target. As the developing world gets richer, however, a move to gas and eventually electricity will be both affordable and have obvious health benefits. Reducing outdoor air pollution turns out to be much more costly.
Better cook stoves and a transition to gas and electricity is an effective use of money that will also help reduce outdoor air pollution. But trying to reduce outdoor pollution with low-sulphur diesel or with filters on cars generally turns out to be too expensive.
While benefits could reach $130 billion annually, the costs could exceed $300 billion per year. Air pollution is one of the world’s biggest and often overlooked challenges. And now we know that one of the best targets for the next 15 years is to get better stoves to 1.4 billion people, saving almost half a million lives each year.
Original article published in Economic Times.