The best approach to chipping away at real estate’s 40% share of global carbon emissions is more uptake of net zero strategies. But what strategies are most effective and, more importantly, how do we get to the elusive Scope 3?
At the property scale, net zero Scope 1 encompasses a building’s direct emissions. This may include lighting, running machinery and heating or cooling occupied spaces. Scope 2 includes indirect emissions created by the production of the energy that a building buys. Many operators will purchase renewable energy credits (RECs) to offset the emissions associated with their power use.
The hardest tier to achieve, however, is Scope 3. This includes indirect emissions all along the value chain such as from suppliers’ products and building occupiers’ energy use. Unlike Scopes 1 and 2, Scope 3 emissions cannot be offset by sourcing RECs.
For new-build projects, there is ample opportunity for decarbonization during the manufacturing, transportation and installation of building materials. Operational carbon can (and will) decrease over time as the power grid becomes cleaner and as operational efficiencies improve. Embodied carbon, on the other hand, is locked in place when the building goes up, which is why it is imperative to support suppliers of lower-carbon materials.
My firm, Lendlease, has pushed the envelope on decarbonized job sites with the use of electric cranes and other heavy machinery. We also have been leaders in procuring lower-carbon materials, including steel and concrete, which both have incredibly carbon-intensive manufacturing processes.
We are repeating this strategy at 3401 S. La Cienega Blvd. in Los Angeles, a transit-oriented, mixed-use project we are co-developing with Aware Super. Like all Lendlease developments, the La Cienega project will be designed to achieve LEED Gold or higher, and the use of reduced-carbon construction materials will help us get there.
Once a building reaches occupancy, then operational carbon becomes a factor. Our U.S. multifamily portfolio has been verified as “net zero carbon,” offsetting 100% of operational carbon emissions, including the carbon footprints created by residents. This is a continuing focus for us on new projects as well.
Our La Cienega project will feature on-site renewables and will be an all-electric building, meaning there will be no gas service for heating, cooking or any other action in any of the building’s 260 residences or across the 250,000 square feet of office space. By extension, this means that the project won’t have scope 1 emissions outside of refrigerants. We will address all of the scope 2 emissions, those associated with electricity, through renewable power procurement. We have done a lot of work with our supply chain and with LCA work internally here to reduce the embodied carbon of the buildings, for example by procuring low carbon concrete mixes and switching the structural design from a prescriptive to a performance-based approach to seismic.
As part of our Mission Zero campaign, Lendlease has committed to achieve net zero for Scope 1 and Scope 2 emissions by 2025 and absolute zero across Scopes 1, 2, and 3 by 2040. The embodied and operational strategies outlined above will help us hit the 2025 goal. Achieving Scope 3, however, is inherently much tougher.
Part of the difficulty is that the target itself is unclear. For example, how far out into the value chain should one look? If an individual leaves their apartment and drives to work, does the carbon impact of that commute fall on the multifamily building or the office building? How do you determine that allocation for a property such as our La Cienega project, which will have both a residential and office component?
These are questions that we and other companies are asking, but the solutions are hard to come by. Without local or federal regulatory guidance, it’s currently up to organizations to decide what is included in Scope 3. Because disclosure frameworks do not focus on Scope 3 emissions, it’s even harder for real estate companies to start making lasting and meaningful progress in this space.
Climate change is a global issue, so it will take a global mindset to combat it. That’s why it is so important to think beyond a building’s footprint. Only by identifying and reducing the numerous sources of emissions that stretch far outside the property line will we be able to mitigate our buildings’ true carbon impact.
(posted 2/23/23)
___
USGBC-LA Note: Please join our “Measuring and Reducing Embodied Carbon in Construction” training on March 22nd.
___
About the Author
Sara Neff is the Head of Sustainability for Lendlease Americas and a LEED Fellow.
