Buildings are responsible for much of global energy consumption, so the need to improve energy efficiency is urgent.
Improving the insulation and ventilation of new and existing buildings will have positive results for both human health and energy consumption.
However, the two must be balanced carefully, say experts at Yale School of the Environment.
Buildings in the U.S. are responsible for 40% of the country’s total energy consumption. By improving the energy efficiency of new and existing buildings, the emissions generated from heating and cooling them could be reduced – preventing thousands of premature deaths every year.
A new paper published in Science Advances, authored by Yale School of the Environment Economics Professor Kenneth Gillingham and colleagues at Yale’s SEARCH Center and the Yale School of Engineering and Applied Science, lays out two building efficiency improvement scenarios and estimates for how many premature deaths in the U.S. would be prevented in each case.
The burning of fossil fuels, in addition to greenhouse gasses, releases large amounts of harmful airborne particulate matter called PM2.5 (particles with diameters of less than 2.5 micrometers), which can cause heart and lung disease and aggravate conditions like asthma. The reduction in premature deaths is primarily due to the reduction in PM2.5.
What is the World Economic Forum doing to promote sustainable urban development?
Cities are responsible for 75% of global greenhouse gas emissions and are home to over half of the world’s population—a number that will grow to two-thirds by 2050. By prioritizing cleaner energy, cities could contribute more than half of the emissions cuts needed to keep global warming to less than 2°c, which would be in line with the Paris Agreement.
To achieve net-zero and nature-positive cities and communities by 2050, the World Economic Forum is partnering with public and private sector stakeholders on initiatives that drive global ambition through local action. Here are just a few:
Davos Baukultur Alliance: Advancing high-quality planning, construction and management of buildings, infrastructure, and public spaces using principles based on climate resilience, sustainability and circularity in the built environment. Learn more.
Global New Mobility Coalition: Exploring new solutions to reduce congestion and emissions, enhance EV infrastructure and transform urban mobility and deliveries. Learn more.
Alliance for Urban Innovation: Connecting innovators and entrepreneurs to new markets and opportunities that reimagine and reshape quality of life and local economies. Learn more.
G20 Global Smart Cities Alliance: Accelerating intelligent, practical solutions to build climate resilience, enhance public well-being and tackle the most pressing challenges facing cities and local communities. Learn more.
Future of Travel and Tourism: Driving inclusive and sustainable economic growth while preserving cultural heritage and protecting natural ecosystems. Learn more..
Discover how you can be a part of our efforts to create more sustainable and livable cities and communities. Contact us here.
The “optimistic” scenario, the authors say, envisions a 50% increase in appliance efficiency (everything from refrigerators to boilers) and a 60-90% increase in the efficiency of buildings’ outer shells by 2050. The researchers estimate that up to 5,100 premature deaths would be prevented yearly if those conditions were met. The “intermediate” scenario – still “a big step up” from what is being undertaken today, says Gillingham – could save up to an estimated 2,900 lives each year.
These estimates of lives saved, however, are focused on changes in outdoor air pollution.
“It is important to also consider the impacts on indoor air quality that may accompany changes in building ventilation,” says study co-author Drew Gentner, associate professor of chemical and environmental engineering and the environment at the Yale School of Engineering & Applied Science.
The potential drawback of the increased energy efficiency of buildings, says Gillingham, is that when buildings are more tightly sealed to prevent leakage of heated or cooled air, the total amount of circulation between indoor and outdoor air also decreases.
“While tighter buildings can partially isolate you from outdoor pollution, it requires greater attention to indoor pollutant emissions,” Gentner says.
For example, inside a home, emissions from cooking or appliances can impact indoor air quality. “If you close the building shell and don't accompany it with recirculation and filtration upgrades, then you can actually face some health impacts,” Gillingham says.
But even without additional indoor air filtration upgrades, the researchers found that improved building efficiency would still save roughly 3,600 per year under the “optimistic” scenario, and 1,800 under the “intermediate” scenario.
The researchers also note that some outdoor air pollution factors, like wildfire smoke, would be reduced indoors if buildings were made more efficient and there was less circulation between outdoor and indoor air. While average outdoor PM2.5 levels have been continually decreasing over time in the U.S., wildfires can sometimes drastically increase outdoor air pollution. And, as recent years have shown, wildfire smoke can spread across large swaths of the country, causing harmful levels of air quality from coast to coast.
“These results, including effects on outdoor and indoor air pollutants, are quite interesting because no one's modeled both before. People have examined similar questions narrowly in small regions, but no one's done it broadly over the entire country,” says Gillingham.
Another factor that Gillingham and his colleagues modeled was the possible effect of a carbon tax. They found that a carbon tax, combined with building efficiency improvements, would save even more lives.
The study helps make clear to people, Gillingham says, that forgoing opportunities to reduce emissions can truly harm people’s health.
