If We Act Together: Keeping 1.5ºC Alive

IF WE ACT TOGETHER

KEEPING 1.5°C ALIVE

BY EDWARD MAZRIA

We are at the crossroads of the most significant crisis and the greatest opportunity in modern times. Cities, architects, and planners must develop and repurpose the built environment to meet the 1.5°C carbon budget.

There’s an old saying in the U.S.: If you don’t know where you’re going, you’ll end up somewhere else. So when we talk about keeping 1.5° C alive, we need to know where we’re going.

The International Panel on Climate Change established a carbon budget in order to meet the 1.5° C maximum global warming, and that is between 300 and 400 gigatons of CO2. That’s how much we can release into the atmosphere and meet the 1.5. What does that mean? Well, today, we emit about 40 gigatons of CO2 a year, which means we need to have a 50% to 65% reduction by 2030 and a phaseout by 2040. That is our timeline. Is it possible?

Building operations are about 25%-27% of emissions worldwide, but if you add in constructing buildings—cement, steel, and bricks—plus interiors, plumbing, site work, and roads—that adds in another 10%. Roughly half of all emissions are attributed to the built environment. How do we achieve a zero-carbon built environment? It’s a two-step process.

Design/Planning & Construction

The first step, design/planning and construction, can get us 70% to 80% of the way there at no cost or low-cost options. And that includes electrification, on-site renewables, no on-site fossil fuels, establishing growth boundaries, transit development, bringing agriculture into the city, designing our buildings correctly, orienting them the right way, the right kind of fenestration, glazing and shading, and what materials and how we build our building. We can even sequester carbon and create carbon-positive structures.

Renewables

The second step is designing for renewables. You need to power the built environment with renewables, which gets us the other 20% to 30% of a zero-carbon built environment. Renewables can be building-integrated renewables or bringing in renewable energy from off-site such as wind, solar, and hydro.

The 2030 Palette is a free online resource for designing zero-carbon, adaptable, and resilient built environments, everything from how we develop our cities and a region down to buildings and building elements.

Sustainable Sites

Sustainable sites maintain and/or regenerate soils and vegetation, manage and filter stormwater, and create advantageous microclimate conditions, like at the Bürkle-Bleiche Senior Living Center in Emmendingen, Germany, by Rolf Disch Solar Architecture.

“THINK OF WHAT WE HAVE TODAY. WE CAN DESIGN ANYTHING, STRUCTURE ANYTHING, AND BUILD ANYTHING.”

©JEREMY BITTERMAN/PALETTE 2030

The Zero Carbon Code

So we have the strategies, and now we have Zero Carbon codes, which can get you very efficient buildings up to 70% reductions in energy consumption. And then, you can use all those other strategies listed above. The formula is the same for existing buildings. High-rise skyscrapers represent about 2% of the total building stock but are the biggest emitters. So we need to start from the largest buildings and work our way down. Cities and districts should provide incentives such as lowinterest loans, tax abatements, equipment, and discount rebates. When a building is sold, a new owner should get it zero. When you come for a zoning, same thing. And governments need to provide incentives for that to happen. If we do that, we get the entire building sector to zero carbon by 2040. But there are hundreds of thousands, even millions, of materials. So how do we get that other 20% to zero carbon?

Just two materials are responsible for almost half of all industrial emissions: concrete and steel. And if you add in aluminum, it goes over 50%. So what do we have to do? We need to change the conversation. And the good news is there’s competition. Mass timber is now being used in high-rise construction. It provides an alternative, and if it comes from sustainably managed forests, it could actually be a carbon-sequester material. CarbonCure has factors where you inject CO2 into concrete and remove it. And we have the first steel company, Econiq, putting out rebar that is net-zero carbon. So no one’s standing still. No one wants to lose market share, and everybody is moving forward.

Think of what we have today. We can design anything, structure anything, and build anything, and look at its energy consumption, whether that’s daylighting, airflow, you name it. And now solar is the cheapest electricity in history, and every year it gets cheaper.

How Are We Doing?

In the U.S., as floor area increased since the Industrial Revolution and we added more buildings, obviously, energy consumption and CO2 emissions went up. But in 2005, something happened: Energy did not go up. It flattened out and went down about 5%. It started to separate from building growth. So we could build but not increase our energy consumption. And CO2 in the U.S. is down 30% from 2005 levels. This decoupling of emissions from floor area growth is unprecedented in U.S. modern history.

How are we doing worldwide? Between 2010 and 2020, building floor area increased 22%. Energy use rose but not as much, and then flattened out from 2018. CO2 emissions essentially fell off a cliff beginning in 2018. And then going through 2020, even though energy consumption didn’t decrease, it was still about the same. We were using the same amount of energy in the building sector, but suddenly, emissions dropped. Why? Because we’re now transitioning away from fossil fuels. The International Energy Agency projected the new normal, renewable power, was the only energy source for which demand increased in 2020. All fuels declined except renewables. And that’s why we’re seeing the reduction now, and we have to keep that up. So we have everything we need now to keep 1.5°C alive. If we act together, we succeed.

East/West Shading

Vertical fins, overhang/fin combinations (eggcrates), awnings, and drop-down shades block the low morning and afternoon sun at the Edith Green - Wendell Wyatt Federal Building in Portland, Oregon, by SERA Architects and Cutler Anderson Architects.

Edward Mazria Founder & CEO, Architecture 2030

Santa Fe, New Mexico

Edward Mazria is an internationally renowned architect, author, researcher, and educator. His seminal research into urbanization, climate change, sustainability, and energy in the built environment has redefined and dramatically expanded the role of architecture, planning, design, and building in reshaping our world. He is the founder and CEO of Architecture 2030, a think tank developing realworld solutions for 21st-century problems. His innovative architecture, planning projects, research, programs, and advocacy have garnered him numerous awards, including the National Wildlife Federation National Conservation Achievement Award and Lifetime Achievement Awards from the National Council for Science and the Environment and Design Futures Council.