Smart Cities Reduce Greenhouse Gas Emission

The smart growth approach focuses on the progress of compact, walkable cities with houses and jobs located close together. By cutting short the commute distance, the urban design aims to aims to cut transportation-related energy use and greenhouse gas emissions.

The researchers from the San Francisco State University conclude after a study that the smart growth approaches to urban planning could cut the number of miles that residents drive in a year.

According to the report that was being published in the B.E Journal of Economic analysis and Policy, this smart growth policy is being followed by California in order to meet emissions reductions set by the state's Global Warming Solutions Ac.

It is estimated that nearly 10 percent of increase in a city's smart growth features would result in 20 percent decline in the number of vehicle miles traveled per household, per year. The features included housing density, jobs per capita and public transit infrastructure. 

"We found that changing the way cities are designed would significantly reduce travel demand," said Sudip Chattopadhyay, professor and chair of economics at SF State. "People's travel habits would change, and they would drive less."

This study contradicts the previous finding that claimed small growth had a small impact on transport demand.

 Chattopadhyay says, "That in the past economists have struggled to find the right methodologies to understand how people's behavior changes in response to urban planning."

For this study, Chattopadhyay developed an innovative way to predict people's behavior, particularly how people make decisions about where to live. He focused on 18 urban areas across the United States and used census data and information from the 2001 National Household Travel Survey and the National Transit Database.

On analyzing the data the researchers found that smart growth strategies yield greater reductions in car use compared to the use of fuel tax increases.

"It's only a few percent points but it is a significant difference," Chattopadhyay said. "Smart growth is a more gradual, long-lasting change and it generates employment. Tax increases can be implemented more quickly but they are subject to change depending on the political situation."