What is life cycle assessment (LCA)?

LCA quantifies resource requirements, environmental releases, and waste through each life cycle stage of a product or system and estimates the associated impacts on human health and ecosystems.  

What is a functional unit?

The results of an LCA are relative to a functional unit, which quantifies the purpose and required performance of the system. The results of two LCAs can be compared only if the functional units are identical. A functional unit can be used as the basis of comparison. Example: Comparing the baseline and alternative coatings based on one or more common performance parameters such as amount of corrosion protection.

See the Life Cycle Assessment Guidance for Principal Investigators Based on Technology Readiness Level for more details under the Guidance Documents Page.    

What is the difference between LCA and life cycle costing (LCC)?

While LCA quantifies environmental and human health impacts, LCC estimates internal costs incurred by the stakeholder, external costs to society (e.g., social cost of carbon), and contingent costs that may be incurred by the stakeholder from future events over the system’s life cycle. The combination of LCA and LCC develops a sustainability analysis.

See the DoD Sustainability Analysis Guidance: Integrating Sustainability into Acquisition Using Life Cycle Assessment for more details under the Guidance Documents Page.  

How do I know if I am required to perform a full LCA? What type of LCA will allow me to meet the Statement of Need requirements?

Refer to the original Statement of Need to determine whether your project requires an LCA. If your project includes an LCA requirement, refer to the Life Cycle Assessment Guidance for Principal Investigators Based on Technology Readiness Level under the Guidance Documents Page as this guidance provides three different procedures to help principal investigators meet their requirement based on their project’s technology readiness level (TRL). The procedures include a semi-qualitative guidance for TRLs 1-4, screening LCA guidance for TRLs 5-6, and comprehensive LCA guidance for TRLs 7-9. The level of efforts may differ based on the TRL. The level of efforts may differ based on the TRL.

What system boundaries should I set for my LCA project?

The system boundary defines which life cycle stages and associated activities will be included in LCA. All stages of the system’s life cycle (i.e., production, operation, sustainment, and disposal) should be considered when defining the system boundaries. However, system boundaries must be relevant in relation to the purpose of the LCA and scope of the study.

See the DoD Sustainability Analysis Guidance: Integrating Sustainability into Acquisition Using Life Cycle Assessment for more details under the Guidance Documents Page.    

What is a life cycle inventory (LCI)? What data should I incorporate into my LCA?

Developing a LCI is the second step of the sustainability analysis framework. The LCI contains all the inputs and outputs associated with any processes that fall within the system boundaries defined in scope of the LCA. LCI data can be included on a mass or cost basis.   

See the DoD Sustainability Analysis Guidance: Integrating Sustainability into Acquisition Using Life Cycle Assessment for more details under the Guidance Documents Page.  

What resources are available to conduct an LCA?

Principal Investigators can conduct LCA using available LCA software (e.g., openLCA, LCA for Experts, SimaPro) or spreadsheet program. Additional LCI databases are also available and can provide more resolution into your LCA. Under the Tools page, principal investigators can refer to the Overview of Available Life Cycle Assessment Software and Life Cycle Inventory Databases document under the Tools Page to understand available LCA software and LCI databases. Note that not all resources are free.

What type of training is available for software?

• This question depends on the chosen software. Software providers may provide a comprehensive user manual, free program tutorials, case studies, and webinars.

Can I use a spreadsheet to conduct an LCA?

• Yes, Principal Investigators can choose to perform their LCAs in a spreadsheet program like Microsoft Excel and download available LCI datasets. Free LCI databases are available in an Excel format such as the Defense Input-Output (DIO) database and Federal LCA Commons databases. Refer to the Templates page in the toolkit to view a Sustainability Analysis Data Collection Template.  

How can I estimate greenhouse gas (GHG) emissions for my project?

In traditional LCAs, total GHG emissions are generally reported for the given system. Principal Investigators can use the DIO database to calculate endpoints such as Climate Change (kg carbon dioxide-equivalent). However, to align with the standard GHG accounting framework referenced in the Executive Order 14057 reporting requirements, it is important to also include a breakdown of direct and indirect GHG emissions by emissions scope. The Greenhouse Gas Accounting Guidance for Principal Investigators under the Guidance Documents Page provides guidance on how to use the Scope 1, 2, and 3 GHG accounting framework when reporting GHG emissions as part of a Sustainability Analysis.