NREL Coauthors U.S. Department of Energy Blueprint to Decarbonize the Buildings Sector

NREL Coauthors US Department of Energy Blueprint To Decarbonize Buildings Sector

A Science-Backed Strategy To Aggressively Reduce Greenhouse Gas Emission by 2050

The U.S. Department of Energy (DOE) has released a Blueprint to aggressively reduce buildings sector greenhouse gas emissions while delivering equity, affordability, and resilience benefits to communities.

Decarbonizing the U.S. Economy by 2050: A National Blueprint for the Buildings Sector reflects the central role that buildings will play in achieving economy-wide climate goals while delivering cost savings, healthier environments, and high-quality jobs. Buildings account for more than one-third of domestic carbon emissions and 75% of all electricity used in the United States. The Blueprint outlines how the sector can achieve ambitious goals to reduce greenhouse gas emissions from buildings by 65% by 2035 and 90% by 2050.

Eric Wilson, senior research engineer at the National Renewable Energy Laboratory (NREL), is on a detail assignment supporting DOE's deputy assistant secretary for buildings and industry and served as a lead author for the blueprint.

"Buildings are where we live, work, learn, and gather as communities," Wilson said. "We are facing an enormous opportunity to impact people across the country with a concerted effort. Working together toward common goals will accelerate building upgrades and create healthier and more secure communities."

To achieve the crosscutting goals, the Blueprint outlines four strategic objectives with specific performance targets that enable overall emission reductions:

• Increase building energy efficiency
• Accelerate on-site emissions reductions
• Transform the grid edge
• Minimize embodied life-cycle emissions.

Each objective has specific performance targets and market, policy, and technology milestones to reach by 2035 and 2050.

"Building upgrades have the potential to increase high-quality jobs, economic security, equity, health, and community resilience," said Carolyn Snyder, deputy assistant secretary for buildings and industry at DOE. "Our national labs are vital partners in helping define strategic focus and in carrying out complex R&D."

NREL Is Supporting Blueprint Objectives

NREL is focused on transforming the buildings in communities across the country and around the world into more efficient, affordable, healthy, and resilient places. More than 150 cutting-edge building science and technologies projects at NREL are collectively supporting the overall goal of equitably enabling net-zero emissions objectives.

Increasing Building Energy Efficiency

The blueprint highlights the critical role of state, local, and Tribal governments in achieving our national objectives and how federal support can bolster these efforts. Communities across the United States are adopting policies to increase energy efficiency and reduce emissions from the built environment. These climate action plans and emission reduction goals need to be rooted in the historical context of the building stock, including energy data, building asset data, and socio-environmental contexts to ensure buildings meet energy and emission targets, while benefiting the people who live in them. And, to achieve measurable sustainability goals, robust and cohesive building data management is imperative.

For example, when a city passes a building performance standard or disclosure ordinance to track energy or greenhouse gas emissions, a covered buildings list is created for a city manager to track buildings over the performance standard's compliance period―typically five years. NREL and Lawrence Berkeley National Laboratory developed the covered building list workflow and Standard Energy Efficiency Data Platform™ (SEED) to help:

• Identify buildings in a jurisdiction and identify which buildings are on which tax parcels
• Explore which buildings would be covered based on property type or gross floor area
• Identify trends across and within building data characteristics and meters and automatically merge identical buildings defined by a unique identifier
• Track building performance over multiple years
• Visualize progress to climate action plan goals for individual buildings and the entire portfolio.

Developed hand in hand with cities to ensure it would meet the needs of its users, the SEED Platform allows disparate datasets to be imported, merged, matched, and linked across multiple years of data imports. This makes for easier tracking of buildings over time and enables integrated timeline views of property changes. Reporting abilities within the platform also help visualize progress on policies and help property owners with compliance or reporting requirements.

"We've been able to partner with organizations to deploy this technology and help drive strategic investments in energy efficiency and beneficial electrification on the local level," said Nicholas Long, senior building researcher and software engineer in NREL's Building Technologies and Science Center. "It's really encouraging to see DOE investments leveraged to make this technology available at scale and help a variety of jurisdictions achieve ambitious energy goals in ways that make sense for them."

SEED allows cities to launch carbon reduction programs quickly and with a limited budget. Not only is the SEED Platform free, but it can also be easily integrated with the other software tools cities use to run their governments. Cities, for example, have linked SEED to Salesforce, a popular customer-relations management tool, so automated emails can be sent to building owners regarding compliance status.

Today, SEED and SEED-based spinoffs are used in 28 jurisdictions across the United States to reduce the energy consumption and greenhouse gas emissions of their building stock, a major step toward a zero-emissions economy that earned NREL an R&D 100 Award in 2022.

Accelerating On-Site Emission Reductions

Space heating accounts for approximately 70% of energy-related on-site emissions in commercial buildings across the United States, and 50% of commercial floor space is conditioned with packaged rooftop units (RTUs).

Heat pump RTUs can lower greenhouse gas emissions and energy costs, but there is room to increase deployment as only 15% of commercial buildings in the United States currently have heat pumps. In cold climates, adoption has been even lower due to the current technology available on the market.

NREL recently co-led the launch of DOE's Commercial Building Heat Pump Accelerator. The initiative will work with stakeholders-from commercial building owners and operators to manufacturers-to accelerate the development and adoption of heat pump RTUs for integrated energy efficiency and electrification of buildings.

"In order to achieve energy-related goals, we know new technologies are needed, specific to commercial buildings in cold climates," said Kelsea Dombrovski, community energy researcher in NREL's Building Technologies and Science Center. "The Commercial Building Heat Pump Accelerator will look at the whole market to understand challenges from building owners, installers, utilities, manufacturers, and more to make a bigger impact."

The accelerator consists of two parts: a campaign and a challenge. The campaign provides building owners and operators with resources and guidance to deploy heat pump technology, supporting both site-level and portfolio-level installations. The challenge asks manufacturers to develop new emissions-reducing heat pump RTUs that meet an advanced technology specification developed by DOE to help organizations meet their energy efficiency needs and decarbonization objectives. Through the challenge, manufacturers will partner with DOE and the national laboratories to create prototypes, test the performance and durability of the products, and lead field validations with partners.

NREL will leverage its industry-leading modeling tools, such as ComStock™, to provide technical support on heat pump performance and impacts. The NREL team will also provide input on additional resources, connections to manufacturers and commercial building owners, and technical insight on the cutting-edge specifications for manufacturers.

"Manufacturers are looking for clear direction as to what the market wants but also what will get us to climate goals in a way that is affordable and meets other constraints, such as size, weight, materials, and compatibility," Dombrovski added. "It's a complex issue that the combined efforts of this accelerator will help solve."

Transforming the Grid Edge

Transitioning to a clean energy future will require the modernization of the electrical grid to accommodate rapidly changing load patterns and new sources of renewable energy. DOE is aiming to transform the grid edge where energy efficiency, clean-energy-ready buildings, electric vehicle charging, and on-site renewable energy generation and storage connect to the power grid. The goal is to shrink the scale of electrical infrastructure required for a 100% clean electricity system by tripling demand flexibility potential by 2050.

A vital step in the transformation is planning future scenarios. Integrated analysis tools are key for stakeholders to better understand what will happen in certain situations and be able to best optimize investments in the grid edge. NREL is improving forecasting analysis that incorporates increased building electrification, electric vehicle (EV) adoption, and deployment of distributed energy resources (DERs) with distribution grid infrastructure improvements.

"It's an exciting time for clean energy. We're installing more clean energy technologies in our buildings and getting more EVs on the road," said Craig Simmons, senior research engineer in NREL's Building Technologies and Science Center. "But the transition also brings complexities such as increased electric demand, varying energy production versus use, and fluctuating customer costs. This energy transition will require a better coordination of devices and systems that interact at the grid edge."

Transformation of the grid edge requires highly granular analytical capabilities that can assess scenarios across a wide range of applications and technologies on both sides of the grid edge, including demand-side equipment and distribution infrastructure. This high level of detail is critical because every distribution feeder is unique and contains specific blends of buildings, EV potential, DERs, and distribution infrastructure.

NREL has a variety of modeling tools that support commercial and residential buildings, EV charging equipment and patterns, renewable energy generation, battery energy storage systems, thermal and district energy networks, and electric grid distribution infrastructure. Many of the NREL tools can be used in coordinated simulations that allow for highly complex bottom-up scenario forecasting analysis.

This strategy supports detailed cost-benefit analysis across assets on either side of the grid edge to support informed decisions for innovative value-add scenarios. Because NREL's tools are open-source, all enhancements directly benefit the forecasting capabilities of any group who will need similar grid edge solutions to the increasing use of renewable generation. The tools also enable neighborhood-level scenario analysis that is essential to improve load management at the grid edge.

"Along with accuracy of analysis, this level of granularity is also an essential component when considering how to invest equitably in grid edge solutions and infrastructure," Simmons added. "Disparities in infrastructure investment happen at the neighborhood and home level. Aggregating or averaging metrics around homeowner characteristics tend to smooth over the sharp correlations that are seen in more granular analysis."

Minimizing Embodied Life-Cycle Emissions

Carbon emissions accounted for outside of the operation phase of a building's life cycles are "embodied" in building materials and equipment, including from resource extraction, manufacturing, transportation, construction, replacement/renovation, reuse, demolition, and material recycling or disposal. New building construction is responsible for an estimated 3% to 7% of total annual emissions in the United States.

Among numerous projects aiming to reduce embodied emissions from building materials and construction, NREL is developing end-of-life embodied-carbon data for high-impact building materials. Researchers working on the Building Re-X project through REMADE are developing a set of open-access databases for construction materials to create open-access Building Re-X models that enable end-of-life considerations to be incorporated into building design and materials selection. Re-X encompasses the reuse, repair, refurbishment, remanufacturing, and/or repurposing of materials.

"Currently, construction sector professionals and researchers cannot objectively evaluate the benefits of various Re-X strategies (reuse/recycle) of construction materials, and most construction and demolition debris goes to landfills," stated Michael Deru, manager of the Advanced Buildings Equipment Research Group at NREL. "There is a need for documented end-of-life reuse scenarios and data for building materials."

NREL is not stopping at creating a database. The project will continue to develop end-of-life methodologies and communicate this information with industry leaders, then integrate this data with top design tools. This project anticipates achieving up to a 7% increase in the annual quantity of Re-X material, 120% increase in annual embodied energy efficiency, and 12% reduction in associated greenhouse gas emissions per year.

Learn more about building technologies research at NREL.