Buildings are a significant contributor to overall carbon emissions. In fact, the built environment accounts for 42%  of global GHG emissions. Non-residential emissions – both direct and indirect – make up one-quarter of the built environment’s share, or just over 10% of total emissions. Looking at key building systems, HVAC contributes about 15% of all emissions (residential and commercial), a point that many of the largest HVAC companies have started emphasizing. These firms view themselves as key participants in decarbonizing the economy. For buildings being designed and constructed today, what steps and strategies should be used to achieve ambitious decarbonization goals? What can be done beyond base building system and equipment selection?

To start, we should highlight why decarbonization is so hard. It requires a few things: capital to invest in projects and upgrades, data to help make sound decisions about where to spend the capital, a capability to plan and execute potentially complex projects, and an ability to realize value from the projects. This last one is the most nebulous, but may include compliance with regulations, brand and marketing benefits, or direct cost savings from reduced energy consumption.

It may be complex for the typical existing building to meet all these requirements. The path may be easier for a new building, if key stakeholders plan for the future. Capital for delivering a lower-carbon building may be slightly more expensive, but spending the money during construction can be more manageable. While there is limited data about the building before it is built, there are fewer data needs. For example, identifying the most impactful equipment upgrades in an existing building depends on performance data and an assessment of age, condition and other factors. For a new building, which will have all-new equipment, such an assessment is less critical. Constructing a new building is complex, so integrating a decarbonization focus into the process should not require additional effort. Finally, substantial value streams can be realized. A new building can be positioned  as a green asset, potentially driving higher rents and increased occupancy. Moreover, regulations may have a greater impact, as the building will benefit from a longer useful life.  This is particularly relevant in an environment where future regulations are expected to be more stringent.

Tactically, there are a few things that stakeholders in new building construction should consider:

• Electrification: New buildings may have a clearer path to electrification. For example, specifications can focus on new HVAC technologies such as heat pumps and heat pump chillers (which can replace the need for a boiler). Batteries and more dynamic control of base building systems may also reduce the need for backup and peak-shaving generators.
• Data normalization: As noted in our previous blog, master systems integration work delivers an integrated data platform across all base building systems. Integrating this work into the initial construction process will streamline building operations, support steps to reduce energy consumption, and enhance capital planning decisions throughout the building’s lifecycle
• Responsive controls: As noted above, more intuitive and responsive controls products, using real-time data, can also drive down energy use. For example, space utilization sensors could be integrated with the HVAC controls, to avoid heating and cooling spaces that are not being used. There are many examples of IOT  sensors being integrated into base building systems, and those decisions can be made during the engineering and construction phase of a new building.
• Staffing considerations: The new building design process should consider engineers and operators. Research indicates that buildings with lower staff turnover tend to achieve more persistent energy savings. Engaging these engineers is an effective strategy for enhancing energy savings.

New buildings represent a much smaller share of overall building stock compared to those already built. The U.S. Green Building Council refers to existing buildings as the “99 percent” due to the sheer numbers and scale. However, incorporating decarbonization strategies in new construction is   a valuable way to showcase success and demonstrate innovative approaches. This, in turn, could encourage decarbonization initiatives in existing buildings as well.

Sources:

1. 1. Architecture 2030, Why The Built Environment
   2. For example, see the March 2024 investor presentation from Trane Technologies
   3. Rental Premiums of Green Commercial Buildings