Asia’s cities could save the planet

The world’s cities will add 2.5 billion more residents by 2050, more than half of them in Asia. The effect on climate change will depend on the kinds of homes, factories and office buildings they live and workin.

Buildings generate almost 20 percent of energyrelated greenhouse-gas emissions — a share likely to rise as farmers move into cities and modern homes. Yet less than 10 percent of the $4.6 trillion spent on construction in 2015 went into energy-efficient “green” buildings.

The reasons are many: Some energy-saving technologies and designs have only recently become widely accessible. Many developers think building green always costs more than traditional methods. Officials in many countries are lax about building codes.

But there is now software that can give architects and engineers access to the most efficient designs. And the International Finance Corp. now estimates that building green raises costs less than 2 percent on average.

Western banks could help marshal new financial instruments, such as green bonds, to pay for new buildings, and Asian governments could do more to encourage greener choices, educate the public and enforce tougher building codes.

If the world’s fast-growing cities can make more buildings more green — as well as their transit, water, waste and other operations — they will play a crucial role in fighting climate change.