Green energy pays for itself in lives saved from smog

New Scientist, Sept. 22, 2013
By Michael Marshall 
Switching to clean energy might seem like the expensive option, but it would pay for itself almost immediately, according to a new analysis. The reason? Reducing our reliance on fossil fuels will cut air pollution, saving lives and therefore money.
By 2050, 1.3 million early deaths could be avoided every year. From estimates of how much society values a human life, researchers deduce that the new energy supplies should be worth the cost.
The conclusion offers a strong incentive to countries to start cutting back on fossil fuels as soon as possible. It also offers support for the US Environmental Protection Agency, which on Friday proposed limiting carbon dioxide emissions from new coal-fired and gas-fired power plants to 499 kilograms [1100 pounds] per megawatt-hour of electricity generated. (On average, a typical coal-fired power station in the US emits 940 of CO₂ kilograms [2072 pounds] per megawatt-hour.)
“The work strengthens the case for these new regulations by pointing out the air quality and health benefits,” says Jason West at the University of North Carolina at Chapel Hill, who led the analysis.

Smog, smog everywhere

As well as releasing greenhouse gases that warm the planet, burning fossil fuels gives off large quantities of polluting chemicals. These can build up into dense smogs, like the one that smothered China’s capital Beijing in January. Such smog is a major public health hazard. West estimates that worldwide, air pollution kills over 2 million people annually.
Now West and colleagues have estimated how much air pollution would be reduced if humanity slashed its fossil fuel use. The team simulated global air pollution in 2030, 2050 and 2100, using two scenarios: one in which humanity cuts its greenhouse gas emissions fairly quickly, and a similar scenario with no global climate policy. Then, using the patterns of global air pollution, they calculated how many people would die as a result of smog, using real epidemiological data as a guide.
In each of the three future years selected, cutting fossil fuels saved lives compared with a control scenario. In 2030, 0.5 million premature deaths per year were avoided, and this rose to 2.2 million in 2100. Keeping these extra people alive means that they can work and continue to contribute to society.

Statistical life

West’s team estimated this economic benefit using a statistic called the Value of Statistical Life. This measures how much value society puts on a person’s life, for instance, by looking at how much people demand to be paid before risking their life.
The team found that for every tonne of CO₂ not emitted, the average global benefit at any one time was between $50 and $380 depending on where you are in the world. In 2030 and 2050, these benefits outweighed the cost of cutting emissions, which was less than $100 per tonne of CO₂. The benefits were less clear by 2100, because by then the easiest reductions had already been achieved so any further cuts were more expensive, at around $300 per tonne. But even then, “the benefits are of the same order as the costs,” says West.
The calculations do not include pollution’s effects on children or the costs of caring for people suffering from pollution-related disease, so the economic benefits may be underestimated.

Short-term gains

If the calculations stand up, the gains from cutting air pollution are greater than expected, says Gregory Nemet at the University of Wisconsin-Madison.
Pollution will only fall if we cut greenhouse gas emissions in the right way, cautions Martin Williams of Kings College London. For instance, burning biomass could be very polluting if done carelessly. “Uncontrolled and inefficient combustion of wood can lead to the emission of lots of particles.”
Even if greenhouse gases are cut, other benefits, like reducing extreme weather events, will not become apparent until the end of the century, according to a recent study by Nigel Arnell at the University of Reading in the UK. That gives politicians a reason to prevaricate.
But the drop in air pollution, and its consequences, changes that equation. “This gives us a benefit that’s immediate,” says West, giving an incentive to act now.
Journal reference: Nature Climate Change, DOI: 10.1038/nclimate2009