Top-down life cycle assessment protocols for all mineralization-based CO2 removal methods

Abstract

As part of the US Department of Energy’s push to accelerate commercialization of CO2 removal, Pacific Northwest National Laboratory and Lawrence Livermore National Laboratory are creating life cycle assessment inclusive monitoring, reporting, and verification protocols for all forms of CO2 mineralization-based carbon dioxide removal. These protocols—produced in partnership with dozens of partners from industry, government, and local communities—are meant to ensure that claimed removals are quantitatively verified based on rigorous science while also providing the implementation flexibility to companies.

The following document discusses unique aspects of life cycle accounting for CO2 mineralization-based carbon dioxide removal. Some of these topics are broadly relevant to carbon dioxide removal, while others are distinct to mineralization-based options. Since carbon dioxide removal requires a net flux of CO2 out of the atmosphere, accounting necessarily involves an assessment of emissions and removals over the full lifecycle of a project. Such cradle-to-grave lifecycle assessment has been used for decades for quantitative analysis of technology options. This document focusses on the areas of traditional life cycle assessment that must be adjusted to ensure the net flux of CO2 from the atmosphere is calculated.

So long as a net removal of CO2 is achieved, “best practice” in carbon dioxide removal may be evaluated from different viewpoints (e.g., scientific, financial, regulatory, political), different values (e.g., equity, economic, justice), and different goals (e.g., maximize decarbonization efforts, minimize temperature increase). To facilitate such multifaceted evaluations, quality levels for life cycle assessment are provided.

Keywords: CDR, MRV, LCA