Decarbonization at Scale: The Portfolio-Level Net Zero Carbon OPR

Our industry is engaged in an important dialogue to improve sustainability through ESG transparency and industry collaboration. This article is a contribution to this larger conversation and does not necessarily reflect GRESB’s position. Please refer to official GRESB documents for assessment related guidance.

As more companies realize the need to decarbonize their real estate portfolios in the face of increasing climate risk and rising investor expectations, guidance on how to transition to Net Zero Carbon (NZC) on the portfolio level is crucial. While most owners and developers are familiar with the typical Owner’s Project Requirements (OPR) to deliver on individual project goals, development teams will need to start by creating a portfolio-level OPR and expand its lens beyond basic OPR strategies to specifically focus on NZC to decarbonize at scale.

Why create a portfolio-level Net Zero Carbon OPR?

Before development teams decide to dive into what can seem like a daunting exercise, let’s lay out the advantages of this approach. So, why create a portfolio-wide NZC OPR? The answer is two-fold:

#1: Portfolio-wide consistency: A portfolio-level requirement is a top-down approach that helps set up the overall policy and requirements for NZC in each individual project. This guiding document is critical for clarity and consistency across all projects in a company’s portfolio.

#2: Net Zero Carbon specific: A NZC OPR goes beyond the typical components of an OPR and adds sections that specifically detail NZC strategies. This provides the owner or developer with clear guidance on how to reach NZC on each individual project across their portfolio.

What’s included in a portfolio-level Net Zero Carbon OPR?

Choosing the best NZC strategies for a company’s portfolio will always depend on its specific goals and resources. That said, many NZC strategies are worth considering when creating a NZC OPR. A few of these key strategies are outlined below.

#1: Integrated Design Charrette

An integrated design charrette allows stakeholders like the investment team, property management, and building occupants to share their perspectives and ideas about the project at a time when their feedback can still be easily and inexpensively incorporated into the design. Hosted by the project team during the conceptual design or schematic design phase, the main goal of this one-time charrette is to establish absolute energy outcome targets, outline a plan to achieve them, and explore design strategies that are most appropriate to achieve the project’s other decarbonization design goals.

#2: Decarbonization Strategies

Some common decarbonization strategies include:

  • Passive Strategies: Optimize building performance by evaluating site climate, building form, orientation, shading, and ventilation that are taken during the early design phase. 
  • Building Envelope:  Ensure an air-tight, highly insulated building envelope encompassing building foundation, exterior walls, roof surface, and sun control and shading devices.
  • Active System Strategies: Consider mechanical systems, refrigerant management, lighting, receptacle load, the power service and distribution system, the plumbing system, irrigation, and landscaping.
  • Electrification: Consider replacing fossil fuel-based systems for space heating and service water heating, as well as cooking and laundry when applicable to go all-electric.
  • Onsite Renewables: After incorporating efficiency measures and prior to investigating off-site renewable sourcing possibilities, explore options to provide renewable energy from onsite sources, which is often done through a Zero Net Energy (ZNE) feasibility analysis.
  • Sustainability Engineering: Use sustainability engineering and building analytical simulation to help identify climate-responsive design strategies at the early design phase, evaluate individual and cumulative impacts of discreet design options, keep track of projected Energy Use Intensity (EUI), and targeted energy savings towards green building certifications, and inform the design process and decision-making with stakeholders.
  • Commissioning: Use commissioning to establish the building operating conditions and parameters, drive quality assurance, and ensure the design and construction meet the project and owner’s needs.
  • Controls & Sub-Metering: Employ a robust energy management system to ensure facility energy is used with maximum efficiency. Teams should consider advanced energy metering to support energy management and identify opportunities for additional energy savings by tracking building-level and system-level energy use.
  • Measurement & Verification: Develop a measurement and verification (M&V) plan to ensure real-time data is collected to measure each building’s ZNE performance once in operations.
  • Owner Training: Have the facility operations and maintenance contractors meet with the design team and commissioning agent to learn about the building systems, controls, and automation systems before taking over maintenance responsibilities.
  • Material Selection: Evaluate building and interior materials for embodied carbon emissions, then employ embodied carbon reduction strategies—typically a material quantity reduction, a material alternative, or a product alternative.

#3: Carbon Credits

Sometimes, implementing all feasible carbon reduction strategies still won’t guarantee a NZC development. In this case, carbon credits can be purchased to offset the remaining annual emissions from the specific development. This Carbon Offsets Guide provides a light framework for selecting a company’s most aligned carbon offsets options.

What about existing assets?

While the NZC OPR approach outlined here is focused on new construction, another step owners and developers can take is to use a similar methodology to create a NZC Current Facility Requirements (CFR) for their existing assets. With both a NZC OPR and CFR, companies are fully equipped to transition their portfolios to zero by delivering NZC projects at scale to meet their corporate climate goals and maximize ESG impact.

Author Bio: This article was written by Wenhan Qiu. At Stok, Wenhan is focused on the continuous improvement and standardization of best practices for commissioning, measurement and verification (M&V), and healthy indoor air quality (IAQ) assessment services for high-performance building projects. As a building performance analytical expert, Wenhan has robust experience in analyzing portfolio-level building performance data for enterprise sustainability reports, including GRESB, GRI, and CDP climate change reports.