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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 glass 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.


Sector Highlights

Industry Description

Four main types of glass are manufactured in the United States: flat glass (e.g., windows); container (hollow) glass; fiberglass; and specialty glass. Glass is made primarily from silica sand, combined with lime, soda, cullet (recycled glass), and other ingredients. The mixture is melted together at a high temperature, then formed and finished into the final product.

Greenhouse Gas Footprint

Washington is home to three major glass manufacturing facilities which together emitted approximately 180,000 metric tons of carbon dioxide equivalent (CO2e) in 2019.1

Industrial Process & Decarbonization

While production methods can vary for different types of glass, the general production process involves blending and grinding raw materials, followed by melting and refining prepared materials, and then final conditioning, forming, and finishing products.

The high temperatures required to melt raw materials cause glass manufacturing to be highly energy intensive and have a high share of energy-related CO2 emissions. 2 Glass manufacturing also has significant process emissions resulting from melting carbonate raw materials (limestone, dolomite, soda ash).

Therefore, decarbonization pathways for the glass industry will involve a combination of measures that reduce energy-related emissions, including fuel switching, 3 electrification, waste heat recovery, and process intensification; 4 and measures to avoid process emissions, such as material efficiency strategies.5 Carbon capture, utilization, and storage could also be used to mitigate process emissions, but its potential use in the glass industry has not been widely investigated and could face numerous challenges.6


The glass manufacturing industry directly supports well over 2,000 workers in Washington state (as seen in Figure 2, employment data are not available for individual employers, such as the one flat glass manufacturing facility in Washington).

1 Washington State Department of Ecology, “Facility Greenhouse Gas Reports,” accessed April 11, 2022,

2 Michael Zier et al., “A Review of Decarbonization Options for the Glass Industry,” Energy Conversion and Management: X 10 (June 1, 2021): 100083,

3 IN4climate.NRW, “HyGlass,” Accessed July 6, 2021.; HyNet North West. “HyNet North West.” Accessed July 6, 2021.; Kopernikus-Project: P2X, “Kopernikus-Projekte,” Accessed July 6, 2021.

4 Zier et al.

5 Ecofys, “Methodology for the Free Allocation of Emission Allowances in the EU ETS Post 2012: Sector Report for the Glass Industry” (European Commission, 2009),

6 Glass Alliance Europe, “The European Glass Sector Contribution to a Climate Neutral Economy” (Glass Alliance Europe, 2019),

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