Location: GLO - Global
The amount of raw materials is calculated based on the composition of flat glass. The total amount of energy is partitioned in 58% from natural gas, 38% heavy fuel oil and 5% electrical. The amount of tin yearly added to the tin bath is assumed to leave the system by air, as part of the particulates. The same with lead. Both emissions are double counted: as particulate and as emission to air. Most other emissions are a mean value of plants with and plants without abatment. It is assumed that half of water evaporates and other half is treated.
Undefined unit processes (UPRs) are the unlinked, multi-product activity datasets that form the basis for all of the system models available in the ecoinvent database. This is the way the datasets are obtained and entered into the database by the data providers. These activity datasets are useful for investigating the environmental impacts of a specific activity (gate-to-gate), without regard to its upstream or downstream impacts.