Data sets currently published in the U.S. LCI Database are presented at a unit process level. This has the benefit of maximizing the transparency of the data, but requires a user to link together all the individual unit processes required to produce a given material or product. This can be a time-consuming and challenging task for individuals unfamiliar with life cycle modeling.
The Plastics Division of the American Chemistry Council (ACC) sponsored the resin project in order to make updated resin production data available not only at a unit process level but also in an easy-to-use “rolled-up” format. The rolled-up data sets include the entire sequence of unit processes required to produce each resin or precursor, including the fuels and energy used for each associated process. The availability of rolled-up data will greatly streamline the process of analyzing the environmental footprint of specific plastic packages and products.
In order to model a specific package or product, a manufacturer can simply take the rolled-up material module, scale it to represent the amount of material used in the product (including any fabrication losses), and add the environmental data for the fabrication or converting process. For example, to model a given quantity of blow-molded HDPE bottles, the manufacturer would multiply the rolled-up HDPE resin module by the weight of HDPE input to the molding process and add the burdens for the electricity required to mold the desired quantity of bottles. (The U.S. LCI Database also includes modules for the production and combustion of process fuels and energy.)
Kudos must be given to the ACC Plastics Division and its members for not only funding this important work but also providing actual plant data necessary to accurately represent current industry practices. It is our hope that publication of the resin data will encourage other material industries to support development of similar data sets for their materials. Keep checking www.nrel.gov/lci for posting of the new plastics data!
For more information on the importance of Life Cycle Inventories to sustainable packaging, please write to Bill Franklin at email@example.com.