We are more eco-friendy in our twilight years (Image: imageBROKER/Superstock)

There is a silver lining to the ageing of societies in the West. Amid fears of rising healthcare costs, soaring pension bills and a declining workforce, it seems that ageing could return Germany to carbon dioxide emission levels not seen since before the 1950s.

The average age is rising in most nations, as people live longer and birth rates fall. This process is most advanced in industrialised nations. Germany has a fertility rate of 1.4 children per woman and a life expectancy of 80. Half the population is aged 46 or older, a world record shared with Japan. Germany has 60 per cent more people aged over 65 than under 14, and a a report earlier this year for the German finance ministry warned that the costs of ageing and declining income-tax revenues could cut the country’s GDP by 3 per cent.

But greyer could mean greener, according to a detailed study of consumption patterns by age group. Fanny Kluge of the Max Planck Institute for Demographic Research in Rostock, Germany, and colleagues found that per-capita CO 2 emissions in Western countries rise steadily as children become adults and as adults become more affluent. But after the age of 60, emissions decline by roughly 20 per cent when individuals retire and travel less.


Universal trend

As a country’s population as a whole ages, it will follow the same pattern, says Kluge. As baby boomers grow into middle age, the country’s emissions soar, but when the proportion of pensioners becomes greater, emissions fall. The dip will be accentuated by any drop in population, if death rates exceed birth rates.

Kluge calculates that since 1950, ageing has caused a 30 per cent increase in German CO 2 emissions. But, after 2020, “as the proportion of people older than 80 continues to increase and the population size shrinks, emissions will decrease and reach pre-1950 levels by 2100”.

The positive effects don’t stop there, Kluge says. The alarming scenario in which pensioners outnumber those in work may have been overstated. The proportion of those aged over 65 in Germany is expected to rise from 21 per cent today to 33 per cent by 2050. But the need to support more pensioners will be compensated by a rising proportion of working women and a fall in the proportion of children.

Health costs will rise, for sure. The average female life expectancy in Germany by 2050 could be 90 years. But, says Kluge, recent studies show that most of the bills for looking after old people occur in the last two years of life, regardless of their actual age. Healthy life expectancy, say the authors, is going up as fast as total life expectancy – but they admit rising rates of dementia could yet confound that trend.

Although the world faces the prospect of 1.5 billion pensioners by 2050, the new work suggests that may not be so bad after all.

Journal reference: PLoS ONE, DOI: 10.1371/journal.pone.0108501