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Economic Evaluation Engine (E3) Technical Manual



Joshua D. Kneifel, David Webb, Luke Donmoyer


The Engineering Laboratory (EL) of the National Institute of Standards and Technology (NIST) has developed a variety of tools that provide some level of economic analysis, many of which have been developed by EL's Applied Economics Office (AEO). AEO-developed tools range across topic areas and economic metrics. Each tool is targeting government agencies and organizations that fall under NIST's mission. Stakeholders need different levels of details and functionality because of the diverse backgrounds across stakeholders. As a result, AEO has developed these software tools in a "one-off" approach on an as needed basis. As a result, each software has its own unique set of code even though these tools have some key underlying components that are common across tools, including methodology documented in standards. To improve the efficiency of the tools developed by AEO and its stakeholders, AEO has developed an economic service/engine with an associated Application Programming Interface (API) that provides consistent, standardized, transparent, reproducible economic analysis calculations should be developed, maintained, and made publicly available for internal and external researchers, analysts, and software developers called the Economic Evaluation Engine (E3). E3 provides economic evaluation capabilities based on ASTM building economic standards including life-cycle cost analysis, benefit-cost analysis, profit maximization / cost-minimization, and risk-cost analysis. E3 could be leveraged by NIST as well as other federal agencies and national laboratories, state and local governments, academia, and the private sector to improve their tool development by using a federally developed and validated calculations to provide standard-consistent analysis. E3 is publicly accessible on a NIST server as well as on GitHub for anyone to use for economic analysis, whether it's through a basic script calling on the E3 API, online interface that connects to the E3 API, or an executable program that is built on E3's capabilities. Additionally, users of E3 could provide expansions to the capabilities by developing the code and submitting it to NIST for review and incorporation. This technical manual describes E3, including the underlying standards on which its based, the data flow through the tool, details on the code libraries, classes, and file structure, development tools used, guidance on how to use the tool, limitations, planned release, and the development of its future capabilities.
Technical Note (NIST TN) - 2225r1
Report Number


Building economics, life-cycle cost analysis, benefit-cost analysis, sustainability, resilience, software, building standards


Kneifel, J. , Webb, D. and Donmoyer, L. (2024), Economic Evaluation Engine (E3) Technical Manual, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed June 22, 2024)


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Created January 18, 2024