The Global Commission on Economy and Climate is planning to put major cities on a plan with larger public transit, smarter waste management and energy-saving buildings. These so called climate-intelligent cities would create a better quality of life and economic expansion, all while drastically decreasing carbon pollution. Depending on whether national governments decide to fund these advancements will depict how much money will be ultimately saved. Researchers found that by 2015, savings could reach up to $22 trillion. However, skepticism towards this notion, like being too expensive or ineffective, run high in the governments' faith. But to the contrary of disbelief, putting cities on a low carbon "trajectory" is shown to be not only sustainable but smart economics. The greater underlying importance here is that by moving towards a cleaner energy source, we are also moving away from use of harmful fossil fuels. The horror of air pollution can be significantly diminished in major urban areas by implementing these ideas, which in turn can quite possibly save people's lives.
http://www.theguardian.com/environment/2015/sep/08/climate-smart-cities-could-save-the-world-22tn-say-economists