Clean and dirty air over a big city

Bringing Back Clean Air

With the promise of vaccines curtailing the spread of COVID, states and economies are beginning to open up again, and we find ourselves getting back not only the good but also some of the negative aspects of pre-pandemic life. Businesses are powering back up, and cars and trucks are roaring down our streets again. As they do, the crisp, fresh air and sparkling blue skies that even city-dwellers experienced over the last year are increasingly being replaced with haze, grime, and invisible pollutants.

As outdoor air quality returns to the forefront, new studies are also showing the deadly toll of indoor emissions—such as from gas stoves and other gas appliances. It is important to remember that the consequences of all this pollution do not fall evenly on everyone. In the United States, a new study just confirmed, yet again, that Black, Latino and Asian Americans are disproportionately exposed to the fine particulate pollution responsible for a host of health ailments.

It doesn’t have to be this way. Last October, RMI addressed air quality issues and highlighted the opportunity for a cleaner recovery in Breathing Life Back into Cities. This report came at a time when the air was particularly clean from the pandemic-induced lockdowns, and the report advised cities on ways to implement recovery strategies to maximize air quality benefits.

In this blog we’ll revisit some of the themes from that report and specifically the actions that cities can still take.


Cleaning up Buildings

While there are many sources of air pollution, the fuels that we burn indoors are the largest driver of premature deaths related to combustion emissions. Currently, burning natural gas and other fossil fuels inside buildings generates 11 percent of total human-made nitrogen oxides (NOX) in the atmosphere. NOX are toxic on their own but also act as precursors to fine particulate matter (PM10 and PM2.5) and ozone, both of which are dangerous to breathe.

Gas stoves are especially problematic. As documented in the RMI report Health Effects from Gas Stove Pollution, these stoves can lead to indoor pollution levels that would be illegal outdoors. And this pollution poses a particular danger to children of color, who have higher asthma rates than White children.

RMI has documented the clear economic case for all-electric homes in new construction, finding that they are cheaper than dual-fuel homes in every major region of the United States. Throw in the safety advantages, and there is simply no reason to build for gas.

Supported by new information about cost, affordability, and safety advantages, 2020 saw massive progress for building electrification. Leading this effort, dozens of cities in California used local codes to mandate that new buildings be all-electric. However, this movement has not gone unopposed. In New England, an all-electric code in the town of Brookline, Massachusetts, was shot down by the state’s attorney general. Recent action by the International Code Council limited the ability of cities and states to participate in new code development. And several state legislatures have either considered or passed laws prohibiting cities from mandating all-electric buildings in new codes.

“These are real threats, but none of them are a death blow to building electrification,” says Mike Henchen, a principal in RMI’s Building Program. He notes that in most states, cities still have the option of setting codes to require that new buildings be all-electric. Another option is passing building performance standards, as New York City, Washington D.C., and St. Louis have done. Finally, cities can incentivize affordable housing upgrades in multi-family buildings, which can help to provide better air quality for low-income people and people of color.


Cutting Automotive Pollution

Cars and trucks are another main source of both fine particulate pollution and NOX, particularly in cities. While much of this comes from burning fuel, even EVs produce both tire wear and road dust, which are significant sources of PM2.5.

From an air quality perspective, the cleanest car is no car. But this is not the only factor. During the pandemic, many cities discovered they could help local businesses survive indoor capacity limitations and social distancing by taking back some of the areas dedicated to automobiles.

This all fits into a larger trend where cities from New York to Paris to Bogotá are finding ways to help residents access services through smarter land use and transportation infrastructure. And similar to electrifying buildings, the move away from auto-centric urban design disproportionately benefits poor people and people of color.

This plays out in two ways. Poor people and people of color are more likely to suffer from the worse air quality near highways. These same communities are also more likely to use public transit and are more often separated from job options and essential services by zoning and other infrastructure choices that prioritize automobiles.

There are ample opportunities for cities to act on this. Cities across the United States have codes that prohibit multi-family housing and mixed-use development over much of their areas. By ending discriminatory land-use, zoning, and transportation planning practices, cities can both clean the air and improve residents’ access to services—particularly those who have historically felt the brunt of racist policies and car-centric choices.

Of course, there is a need for electric vehicle (EV) charging, as well. EVs provide air quality benefits versus gas-powered vehicles, and a need for some motorized vehicles will remain. To encourage a rapid build-out of an EV charging network, cities can lower permitting costs, identify optimal locations for fast-chargers, and work with electric utilities to ensure rational rate design for these chargers.


Greening the Gray

While parks, trees, and other green spaces may not immediately come to mind when you hear “climate tech,” nature-based solutions are emerging as key strategies to reduce temperatures, pollutants, and flooding in cities. These projects range from small, simple projects like green screens or community gardens to large city-wide initiatives to reduce wastewater overflow or develop parks within a 10-minute walk of every resident.

Even at the smallest scale, these things have an impact. Green screens—a barrier of greenery between roads and sidewalks, parks, or schools—have proven effective in blocking vehicle pollutants. A study in London found that a simple ivy green screen between a playground and major traffic corridor reduced children’s exposure to NOX by 24 percent and PM10 by 38 percent.

On the other hand, some cities approach these solutions more holistically. RMI’s Coming Back Stronger report highlights the City of Denver’s 20-year Game Plan for a Healthy City, which aims to expand tree canopy to 20 percent of its land cover and ensure that every resident is within a 10-minute walk of a park. In 2017, the city voted to increase sales tax by a quarter-percent to generate revenue for these plans.

The City has been working closely with local stakeholder groups to ensure equitable implementation and access. It is locating parks near key community centers like schools or where they can provide improved and safer commutes by connecting existing bike lanes or bus routes.


Getting Utilities to Clean Up Their Act

In addition to acting locally, cities need to think bigger. A highly electrified city has less value if it draws its electricity from dirty fossil fuel plants. In Breathing Life Back into Cities, we highlighted an opportunity for North Carolina cities to influence Duke Energy’s grid mix by intervening in the 2020 integrated resource plan (IRP) process.

Duke proposed building 8 gigawatts of new natural gas plants, more than any utility in the United States, over the next 14 years. North Carolina cities decided to weigh in. In February, a record 13 cities and counties formally submitted comments on Duke’s IRP, urging the North Carolina Utilities Commission to require Duke to reevaluate the health and economic impacts that keeping coal online and building new gas plants would have on its customers.

The City of Charlotte’s comment specifically ties energy to public health:

“Along with contributing to climate change, pollution from coal plants is linked to lung conditions like asthma, heart conditions, and brain and nervous system conditions, all of which disproportionately affect low-income and Black and Brown communities.”

Due to these concerns, the City emphasized its interest in two of Duke Energy’s planning scenarios based on “earliest possible retirement” for coal plants and “no new gas generation.”  The commission should approve or request specific modifications to the IRP, based on their review of all information, by the end of this summer. Given that 36 states require utilities to file IRPs every two to three years, there are many opportunities for other local governments to follow these North Carolina cities and start impacting air quality at a state and regional level.


Leadership Is Needed

While cities are major actors, there is also a significant role for the federal government.  Congress is currently discussing President Biden’s $2.25 trillion infrastructure package that consists of a variety of technologies, policies, and practices that could clean the air. And looming on the horizon is the reauthorization of the surface transportation bill, which could serve as an opportunity to rebalance our priorities between funding highways and public transit.

However, cities should not wait on federal government action. Instead, cities must utilize opportunities to clean up their air and re-emerge from the pandemic as stronger, more equitable communities. It is going to be up to city councils, mayors, and other local decision-makers to continue to step up and lead the way to a future of bluer skies and cleaner air. We can do this.