Aluminum

George Estreich

About the Project

The Clean Energy Transition Institute, in collaboration with SEI-US, and under the direction of Derik Broekhoff, produced a Washington State Industrial Emissions Analysis for the Washington Department of Commerce in July 2021.

This Clean Materials Manufacturing project expanded upon that analysis for six manufacturing sectors—aluminum, concrete and cement, glass, iron and steel, pulp and paper, and wood products—to provide background material for Building Washington’s Clean Materials Manufacturing Economy.

You will find the aluminum manufacturing sector documents below:

  1. Manufacturing Sector Overview: This document explores the industry’s greenhouse gas footprint, industrial process, decarbonization strategies, and Washington workforce.
  2. Emissions and Decarbonization Strategies: This flowchart shows each step of the industrial process along with the associated emissions and relevant decarbonization strategies.
  3. Manufacturing Energy and Carbon Footprint: This document, published by the Advanced Manufacturing Office of the Department of Energy, maps the flow of energy supply, demand, and losses as well as greenhouse gas emissions for the sector.

Aluminum

Sector Highlights

Industry Description

After steel, aluminum is the second most used metal in the world. 1 Aluminum is made either through primary production (making new aluminum from bauxite ore) or secondary production (recycling existing aluminum into pure metal).

Greenhouse Gas Footprint

There were three aluminum facilities in Washington with over 10,000 metric tons in annual carbon dioxide equivalent (CO2e) emissions between 2016 – 2020, which together emitted roughly 1.2 million metric tons of CO2e in 2019. 2 Of these three, one is a manufacturer of aluminum sheet, plate, and foil (Kaiser Aluminum in Spokane), while the two others were aluminum smelters, both of which have since been idled or decommissioned. Alcoa Intalco Works in Ferndale was idled in 2020, explaining the emissions reductions seen between 2019 and 2020 in Figure 1.

Note: Figure 1 shows only direct reported emissions and does not include emissions from electricity, which account for approximately two-thirds of the aluminum industry’s global emissions.3

Industrial Process & Decarbonization

Primary production consists of two main steps: alumina refining, in which aluminum is chemically extracted from mined bauxite, and smelting, which converts alumina into pure aluminum through electrolysis.

Smelting is responsible for 77% of the aluminum industry’s emissions, a large portion of which arise from electricity consumption, making decarbonization of electricity used by aluminum smelters worldwide a key strategy for the industry. 4

In addition to emissions from electricity usage, the electrolysis process also causes a chemical reaction that produces CO2 and perfluorocarbons (PFCs). Decarbonization strategies must involve technological innovations and methods that would attempt to eliminate these process emissions. 5

Secondary production of aluminum (recycled aluminum as the raw material) uses only 5% of the energy needed in primary production and using more recycled aluminum is a key decarbonization strategy. However, recycling must be paired with other decarbonization strategies as the availability of scrap metal may not be able to meet the growing demand for aluminum.6

Workforce

Washington employment numbers in the aluminum manufacturing industry have fluctuated as smelting plants closed during the past five years. According to 2020 employment data, the aluminum manufacturing industry was directly supporting over 250 workers in Washington state. However, the real number is much higher; as seen in Figure 2, employment data are not available for individual employers, such as the Alcoa aluminum smelter.

1 Jonathan Maes, “18 Different Types of Metal (Facts and Uses),” Make It From Metal (blog), accessed May 13, 2022, https://makeitfrommetal.com/different-types-of-metal-facts-and-uses/.

2 Washington State Department of Ecology, “Facility Greenhouse Gas Reports,” accessed April 11, 2022, https://ecology.wa.gov/Air-Climate/Climate-change/Tracking-greenhouse-gases/Greenhouse-gas-reporting/Facility-greenhouse-gas-reports.

3 Tiffany Vass et al., “Aluminium” (International Energy Agency, November 2021), https://www.iea.org/reports/aluminium; World Economic Forum, “Aluminium for Climate: Exploring Pathways to Decarbonize the Aluminium Industry,” November 2020, https://www3.weforum.org/docs/WEF_Aluminium_for_Climate_2020.pdf.

4 World Economic Forum.

5 Derik Broekhoff, Silvia Ulloa, and Jason Veysey, “To Decarbonize U.S. Industry, Look to Federal and State-Level Partnerships - Leadership Group for Industry Transition” (Leadership Group for Industry Transition), accessed March 28, 2022, https://www.industrytransition.org/insights/decarbonize-us-industry-federal-state-level-partnerships/.

6 World Economic Forum.

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