Metrics and Tools for Sustainable Buildings

Summary

Building stakeholders need practical information that aids investment and policymaking decisions related to sustainable, high performing building designs, technologies, standards, and codes. This project addresses these needs through standards-based performance data, metrics, and tools for building products and whole buildings. It is focused on life cycle analysis of building construction and operation using Life-Cycle Cost Analysis (LCCA) and Life-Cycle Assessment (LCA) combined with whole building energy modeling to account for the integrated nature of building systems and impacts on occupants.

Over the prior four years, this project prioritized developing two modularized tools (APIs) that are interoperable with existing and new software to assist technical audiences in incorporating sustainability analysis into other platforms. First, the Economic Evaluation Engine (E3) provides topic-agnostic ASTM standards-based economic analysis of engineered systems that facilitate development of user applications across multiple research areas within the Engineering Laboratory (EL) at NIST. E3 is expected to streamline the development of such economic analysis tools as demonstrated by E3’s initial use case, [PV]², that evaluates the economic and environmental performance of residential solar photovoltaic systems. Second, BIRDS NEST provides to software developers and building modelers an assessment of the whole building environmental impact of residential buildings by developing interoperability between whole building simulation and LCA databases and software using a standardized data format. BIRDS NEST allows software developers and building modelers to include whole building LCA (WBLCA) results into their existing capabilities without requiring LCA expertise. In FY24, the focus of this project was on: (1) expansion of E3 adoption within EL-developed decision support tools, (2) development of “how to” guidance for use of E3 by researchers, (3) validation of a public-facing BIRDS NEST API and associated OpenStudio Measure using the NIST NZERTF as a use case, (4) development of a plan and beginning the updating of the underlying building system and operational energy LCA data, (5) coordination with other federal agencies (e.g., EPA and DOE) to assess data gaps and needs in public LCA datasets to improve the comparability, transparency, and quality of Environmental Product Declarations (EPDs) for building products, and (6) collaboration with ASTM to hold a workshop and publish a report on LCA standards needs for decarbonization.

The focus of this project in FY25 will be on expanding awareness/use and capabilities of the software tools through the following:

• Complete a case study highlighting the capabilities of BIRDS NEST.
• Publish updated operational energy LCA data across different future scenarios.
• Complete a comparison study of publicly available dynamic on‑site operational energy LCA data
• Publish LCA models and results for building systems for inclusion into BIRDS NEST.
• Provide support for both internal and external tool development using the E3 API, as needed.
• Update the underlying data and incorporate additional features and capabilities into [PV]².
• Assess the value add of new features for E3, E3-based tools, and BIRDS NEST and additional decision-support tools that could be provided for stakeholders (i.e., software requirement specifications and development plans).

In addition to the tool-related activities, this project will continue to participate in and publish on the LCA background dataset standardization and gap assessment efforts started in FY24 to improve LCA of building products and whole buildings. Also, cross-project and cross-program collaborations will be explored to provide a more holistic approach to related research activities within EL and across NIST laboratories.

Description

The Metrics & Tools project assesses whole building sustainability for buildings located in 228 U.S. cities.

Objective
To develop and deploy transparent, open source standards-based data and tools that quantify the life-cycle cost and sustainability performance of building technologies and systems by 2027 through parallel activities focused on developing, releasing, and expanding capabilities and adoption of: (1) an economic evaluation API that is interoperable with other software, (2) web applications leveraging E3 to provide additional stakeholder value, (3) a WBLCA API for single-family homes that is interoperable with existing software, (4) transparent, consistent, up-to-date on-site operational energy LCA data accounting for present and potential future dynamics of energy markets, and (5) LCA-related standards and data and to address the needs of standards development organizations (SDOs), the LCA Community (i.e., American Center for Life Cycle Assessment – ACLCA) and other federal agencies (i.e., Federal LCA Commons MOU and activities).

Technical Idea
The technical idea is to develop, release, and disseminate standards-based information, data, metrics, and tools to improve investment choices and policymaking related to sustainable, high performing building designs, technologies, standards, and codes. This project focuses on life cycle analysis of the economics and environmental impacts of building construction and operation using LCCA and LCA combined with whole building simulation to account for the integrated nature of building systems and impacts on occupants.

Prior research included the development of support tools that focused on the needs of a range of technical and non-technical stakeholders in making sustainability-related decisions in the built environment, both at the building product and whole building levels. BEES was developed to allow sustainability performance comparisons across similar building products without the need for expertise in quantifying sustainability. Additionally, BIRDS was developed to expand the scope of sustainability-related decisions to the whole building level by addressing the quantification of building sustainability in a holistic, integrated manner that considers complex interactions among building technologies and systems across dimensions of performance, scale, and time. Limitations of these all-in-one tools is the high cost and time required to maintain and update underlying data and user interfaces as well as the increasing capabilities of other building-related software. More recently, this project has transitioned its focus onto data development and modularization and interoperability of life cycle analysis tools that allow for inclusion of building sustainability criteria and metrics in other building-related decision tools without the need for extensive expertise.

BIRDS NEST generalizes the BIRDS framework and data sources to allow for evaluation of the environmental performance of real-time custom whole residential building designs using WBLCA across the building’s service life. The BIRDS NEST API is being designed to be interoperable with multiple existing and future tools, including whole building simulation and building energy rating software. BIRDS NEST provides a standardized data exchange format to send and receive building information for LCA modeling and results. Additionally, BIRDS NEST has implemented a new dataset for on‑site operational energy LCA data that accounts for potential future dynamics of energy markets using the most recently available emissions data and future scenarios.

E3 is a topic-agnostic economic analysis tool for engineered systems. The E3 API provides multiple economic analysis capabilities in a consistent format using ASTM standards. E3 provides a range of economic evaluation capabilities, including LCCA, benefit-cost analysis (BCA), profit maximization, monetary and non-monetary trade-off analysis, sensitivity testing, and uncertainty analysis. E3 is expected to streamline the development of future economic analysis tools developed by AEO as demonstrated by E3’s initial use case, [PV]². [PV]² is a web application designed for homeowners and solar PV installers to use in evaluating the economic and environmental performance of residential solar PV systems over their service lives. E3 can also be leveraged by other EL/NIST researchers as well as by external stakeholders to evaluate topic areas across EL goals and programs.

In addition to tool development, this project is collaborating with ASTM, ACLCA, and the Federal LCA Commons federal agency members to identify standards and data gaps and needs that must be addressed to improve the quality, transparency, and comparability of building product and system LCAs.

Research Plan
Research to date under this project has led to three decision-support tools (and associated publications) at different product stages: BIRDS NEST, E3, and [PV]².

NIST used the underlying framework from BIRDS, a whole building sustainability performance tool developed under a previous iteration of this project, to develop BIRDS NEST, which allows for sustainability evaluation of user-defined residential building designs in real time without the need for the user to have technical expertise in LCA nor pre-processed databases. NIST has collaborated with Athena Sustainable Materials Institute (ASMI) to combine the capabilities of ASMI’s Impact Estimator for Buildings (IE4B), including all common single-family home building envelope and systems, with building component options and operational energy data in BIRDS NEST using the HPXML standard format. NIST also created input / output enumerations and example files based on HPXML to ensure interoperability across tool platforms. Additionally, NIST collaborated with NREL to develop an OpenStudio Measure that allows OpenStudio users to easily submit BIRDS NEST requests, providing a use case for BIRDS NEST and allowing any modelers or software developers using the OpenStudio applications and/or SDK to leverage BIRDS NEST. In FY21, an internal testing, debugging, and validation of BIRDS NEST was completed using OpenStudio models based on the NIST NZERTF and PNNL Residential Prototype Building Models. In FY22, BIRDS NEST was made live (with approved access) and validated and incorporated new on-site operational energy LCA data produced through an agreement with DOE’s NETL. In FY23, the OpenStudio Measure was updated to align with NREL’s Building Component Library Ruby GEM requirements and improve readability and processing speed, and the dynamic on-site operational energy LCA data from the NETL collaboration was incorporated into the BIRDS NEST API. In FY24, I BIRDS NEST OpenStudio Measure was published on NREL’s Building Component Library (BCL) for public access and validated. A plan was developed, and efforts were started to update the underlying LCA models for building systems and operational energy data used in BIRDS NEST. 

In FY25, the new LCA data for building systems and operational energy will replace the existing data in BIRDS NEST. A collaborative study based on a common test case will be completed using BIRDS NEST and IAQ evaluation tools developed by the IAQ Group in BEED (e.g., CONTAM) in combination with economic analysis in DOE NREL’s BEopt to highlight the capabilities within the program of assessing a range of building performance evaluation criteria and metrics and the potential benefit of improving interoperability of building analysis tools. Targeted external access will be provided to complete external validation of BIRDS NEST. A study will be completed to compare publicly available dynamic operational energy and LCA data to assess areas for improved accuracy, consistency, and transparency.

The fourth industry support tool under this project is the Economic Evaluation Engine (E3), which is an API that provides an array of economic evaluation methodologies based on ASTM standards, including LCCA and BCA. By design the E3 API allows any software tool (e.g., script, executable, web interface) to call on the API and ensure the calculations are providing standards-based results. The fifth industry support tool, Present Value of PhotoVoltaics ([PV]²), is a web application that allows homeowners to determine a complete cost of ownership for residential rooftop solar photovoltaic (PV) systems including purchase and operation through the system’s service life as well as the associated greenhouse gas (GHG) emissions relative to consuming energy from the electric grid. [PV]² is the first tool Powered by E3. In FY21, a beta version of E3 and a pilot web interface (Present Value of PhotoVoltaics – [PV]²) were developed as proof of concept. In FY 22, both E3 v1 API and [PV]² were made “live”, validated, and publicly released. In FY23, E3 was expanded to include uncertainty analysis (E3 v2) and validated using examples from existing software (i.e., [PV]², BLCC, EDGe$) and ASTM standards (ASTM E3200). E3 v2 replace E3 v1 as the publicly available API. [PV]² was transitioned to use the E3 v2 API. E3 v1 was archived and remains publicly available on GitHub. Also, an E3 module that introduces EDGe$ capabilities was designed and published on GitHub. In FY24, E3 support resources were expanded to include “how to” documentation on leveraging E3 for building web applications, building modules to expand E3 capabilities, and using computing platforms (e.g., Jupyter Notebook) to call on E3 for research applications. E3 support was provided for the redevelopment of the Building Life Cycle Cost (BLCC) software tool for DOE FEMP as well as for a manufacturing capital investment tool (SITExpress). 

In FY25, E3 support will continue to be provided for both internal and external tool development using the E3 API, as needed, including for SITExpress and BLCC. The underlying economic and LCA data will be updated in [PV]², and new features will be incorporated to improve the usability and functionality for users. A mock interface will be developed for a tool that can analyze a variety of residential building system investment decisions (e.g., battery storage, heat pumps).

In addition to these activities, this project will assess the value added of new features for these existing tools and/or additional decision-support tools that are identified as potentially beneficial for stakeholders. Also, researchers will participate in coordinated LCA dataset standardization efforts to improve transparency, consistency, and trustworthiness of LCA modeling of building products and whole buildings. Current activities include: LCA data gap assessment related to NIST involvement with EPA’s Interagency Leadership Team on Background Data; participation on ACLCA’s Board and appropriate Committee activities, including assisting in development of a pilot Conference LCA tool; and coordination with ASTM on assessing LCA standards. Also, cross-project and cross-program collaborations will be explored to provide a more holistic approach to related research activities in EL and NIST, including building and infrastructure related activities in the Net Zero Energy High Performance Buildings Program, Circular Economy Program, Carbon Capture and Accounting Program, and Community Resilience.

Major Accomplishments

Outcomes:

• BIRDS v1.0 released in September 2014;
• New technical expertise in energy simulation and top-down LCA enabling science-based sustainability assessment of whole building energy, environmental, and economic performance on a life-cycle basis.
• New database for U.S. building sustainability assessment covering 228 locations, 12 building types, and 5 levels of energy efficiency.
• New guidance for policymakers on benefits and costs of energy codes.

Impacts:

• The environmental importance weights developed by the BEES Stakeholder Panel are used in LEED version 3 and standardized in ASTM E1765-11 for Multiattribute Decision Analysis.
• 50,000 Unique Visitors to BEES Online in its first year.

Standards and Codes:

• Expected impact: Adoption of more efficient and cost-effective energy and green construction codes by states currently using outdated or no codes.
• B. Lippiatt, International Green Construction Code Committee.

Associated Product(s)

 

BEES (Building for Environmental and Economic Sustainability) software