People will likely need to live in smaller houses and denser neighborhoods for the United States to drive down residential greenhouse gas emissions consistent with global climate goals, according to new research published Monday by researchers at the University of Michigan.
The shift is just one of several policy and cultural changes required to cut emissions from U.S. households consistent with long-term targets under the Paris climate agreement, according to the researchers. The U.S. will also need to slash emissions from electricity, retrofit older houses to be more energy efficient, and begin phasing out direct use of fossil fuels, such as fuel oil and natural gas, in heating homes.
Those changes would likely face opposition, particularly from Republicans and conservatives who have defended suburban living.
Currently, around 20% of U.S. energy-related greenhouse gas emissions come from heating and powering people’s homes.
“It does require a change in thinking” about how people live, as well as structural changes in the energy and housing sectors, said Benjamin Goldstein, a postdoctoral research fellow at the University of Michigan’s School for Environment and Sustainability and lead author of the study.
“We can design new neighborhoods in different ways that require less energy,” Goldstein said.
The research found density must increase by 19% on average to meet a goal to cut household emissions 80% by 2050. That would mean building fewer single-family homes.
The floor area per capita of U.S. homes would also need to be 10% smaller than the current average, the researchers found. States such as Colorado and Florida expected to see significant population growth would experience even larger reductions in floor area per capita, of 26% and 24%, respectively. The researchers note, however, that even with those reductions, U.S. home sizes would be similar to those in other wealthy nations.
Changes in home sizes and neighborhood density should be coupled with, and in some cases driven by, policy changes, the researchers say.
“These include broad and extensive decarbonization of the energy grid as well as aggressive energy efficiency measures,” said Josh Newell, an associate professor at the University of Michigan’s School for Environment and Sustainability and a study author.
“State and local governments, where appropriate, will also need to develop policies that encourage density and smart growth,” he added.
A major challenge, however, would be encouraging changes in U.S. households without exacerbating a disparity that already exists between denser, and often poorer, neighborhoods and wealthier neighborhoods where houses are bigger and more spread out.
The University of Michigan researchers found wealthier households have a carbon footprint at least 25% higher than poorer homes, which often tend to spend more of their paychecks on energy costs and are less likely to be able to afford efficiency upgrades.
Los Angeles, for example, is a “tale of two cities from a carbon perspective,” Goldstein said. Beverly Hills, with its massive mansions, has a carbon footprint per person about 10 to 15 times higher than poorer neighborhoods just a few miles away, he said.
Addressing that disparity starts with people recognizing how much more wealthier households emit, Newell said: “This then forms the basis for a collective discussion about equity with respect to emissions and our respective responsibilities to reduce them.”
