In December 2008, Glass Packaging Institute (GPI) member companies agreed to the goal of using at least 50 percent recycled glass in the manufacture of new glass bottles and jars by 2013.

This target recognizes the growing need to protect the environment and conserve energy. Energy costs drop about 2 to 3 percent for every 10 percent of cullet used in the glass manufacturing process. Using the U.S. Environmental Protection Agency's (EPA) benefits calculator, the GPI estimates that the energy saved by using 50 percent recycled content in all glass packages manufactured in the United States could power more than 45,000 households for a year.

Beyond energy benefits, the use of cullet saves natural raw materials — sand, soda ash and limestone — ton for ton. And recycling glass containers provides for a reduction in carbon dioxide (CO2) emissions. For every six tons of recycled container glass used, a ton of CO2, a greenhouse gas, is eliminated. A relative 10 percent increase in cullet reduces particulates by 8 percent, nitrogen oxide by 4 percent and sulfur oxides by 10 percent.

So, how will the industry achieve this goal? As an end-user market for the majority of cullet that is collected, the glass container industry is prepared to pursue measures that efficiently and cost-effectively improve glass recovery.

Collection and Cullet Quality

To start, the GPI has long been committed to promoting recycling in the United States. Its member companies were early proponents of drop-off collection centers and later of curbside recycling. The industry has also actively supported efforts to initiate best practices for single-stream curbside collection.

The trend to single-stream recycling impacts the quality of all materials recovered, and especially glass containers, compromising the use of this material for the manufacture of new glass bottles. A 2008 study in northern Colorado on best practices for glass recycling found that the glass capture rates from single-stream collection may only reach 30 percent. That rate increases to almost 100 percent for drop-off collection programs.

To untangle all the recyclables, the focus is on expanding and improving handling and sorting technologies. This includes optical sorting equipment at materials recovery facilities and more glass processing plants to remove contaminants and color sort glass. About 73 cullet processors in 29 states continue to investigate new technologies to improve cullet quality, allowing recovered glass to remain a viable commodity for bottle-to-bottle recycling.

New Sources for Recycled Glass

Looking beyond the curb for high-quality cullet, glass manufacturers are encouraging bottle recycling in commercial settings such as bars, restaurants, wineries and hotels. Glass can comprise up to 90 percent of that packaging mix. With the encouragement of new laws, nearby glass markets and local activism, bar and restaurant recycling initiatives are taking shape in states like California, Colorado, Indiana and North Carolina.

In North Carolina, for example, a 2008 law requiring alcohol beverage control (ABC) permit holders to recycle beverage containers yielded an additional 40,000 tons of these recyclables in 2008, according to the N.C. Division of Pollution Prevention and Environmental Assistance. Ten new businesses have been established for recycling and hauling services, and of the 8,500 ABC permit holders — mostly bars and restaurants — more than 7,500 are in compliance with the law. Glass processors also have noticed an increase in the quality of the recovered glass.