ECOCLASS Glossary of important terms

Vehicle occupation ("Besetzungsgrad")
Number of persons traveling in the vehicle at the same time. When averaged values are used, non-even numbers are possible - the average occupation of cars is 1.3 - 1.5 persons.

CO2 equivalent
CO2-Equivalents are the result of aggregating greenhouse gas emissions according to their global warming potential and serve as an indicator for the climate impact.

ECOCLASS
ECOCLASS is short for "ECOlogical and CLimatic ASsessment of product systemS". It is a software to calculate ecologically and climatologically relevant emissions of product systems. Currently, this is limited to urban transport systems.

GEMIS
GEMIS is short for "Global Model of Emissions of Integrates Systems" ("Globales Emissions-Modell Integrierter Systeme") and has been developed by the German Öko-Institut e.V.. GEMIS is a database and offers the possibility to do product life-cycle analyses. The GEMIS database (version 4.2) covers more than 7000 processes and more than 1000 materials.

Input
Used to indicate materials and energy types that are necessary for a process to generate its output. The value shown is the amount of input units (i.e. pieces, kilograms or Megajoule) necessary to produce one unit of output.

Navigator
Part of the ECOCLASS workbench, where projects and product system editors are managed. Its function is similar to that of a file manager.

Utilization process
Process that describes the utilization of a vehicle. Together with the inputs of material and energy, these parameters define the emissions per kilometer. Each ECOCLASS process chain has exactly one utilization process.

Ozone
Ozone (O3) is a reactive molecule of oxygen and - when found near earth's surface (tropospheric ozone) is considered to be a pollutant which is one of the major components of summer's smog. In the higher atmosphere, ozone absorbs ultraviolet radiation from the sun (ozone layer). Ozone is also a (minor) greenhouse gas. Ozone depletion in the higher atmosphere, causes e.g. by halocarbons, is a global environmental problem, whereas high tropospheric ozone concentrations are a local/regional problem with direct impact on human health.

Ozone formation potential
Ozone formation potential in GEMIS is the mass-related equivalent of forming tropospheric ozone from precursor molecules, which thereby lead to summer's smog.It is expressed in tropospheric ozone precursor potential equivalents (TOPP).

Output
Product or Service, which is generated by a process. Each process generates exactly one unit of output.

Palette
Part of the product system editor where elements to build product systems are collected, e.g. flows, reference flows, utilization processes, etc. These elements are activated by dragging & dropping onto the product system editor.

Person kilometer (Pkm)
Unit in personal transport indicating that one person travels one kilometer. Vehicle occupation is essential when comparing to the distance: 4 Pkm can be achieved by a car with four passengers that drives 1 km. If the car is occupied by only one person, it is necessary to go 4 km to get the same 4 Pkm. Emissions are 4 times higher in the second case.

"Personentransport-Dienstleistung"
Translates as "personnel transport service" and is used to describe the outputs of utilization processes and the inputs of reference flows. It is directly taken from the GEM'S database and used there to indicate quantities that have the unit person kilometer.

Product system
The combination of one or more process chains within a product system editor. Since each process chain describes the utilization of one vehicle, this allows to construct ways where several vehicles are used one after another. The sum of person kilometers in all reference flows indicates the total travel distance of one person.

Product system editor (PSE)
Part of the ECOCLASS workbench where product systems are edited. Each PSE contains a product system. All opened PSEs (i.e. those visible with a tab in the workbench) are considered when emissions are calculated. Sometimes, a product system editor is also called a model (e.g. in the Navigator).

Project
Administrative unit for product system editors (models) in the Navigator. Each product system editor is part of a project, although product system editors of different projects can be opened simultaneously and thus be compared in the workbench.

Process
A process combines inputs (upstream products and energy) in a defined relation to produce one unit of a product (output). There are two kinds of processes in ECOCLASS: utilization processes allow the user to modify the combination of inputs by the way the process is utilized, while upstream processes have a fixed combination of inputs determined by the GEMIS database.

Process chain
A chain of processes representing the conversion steps of upstream products and energy into a final product or service. Currently, the final service in ECOCLASS is always one kilometer distance traveled by one person using a vehicle that is represented as a utilization process. The upstream processes which produce the inputs of the utilization process, can be displayed and partly also be altered.

Reference flow
Defines the type and amount of the final product or service produced by a process chain. In ECOCLASS is always one kilometer distance traveled by one person using a vehicle that is represented as a utilization process (cf. Person kilometer).

Sulfur dioxide (SO2)
Sulfur dioxide is an acidifying gas that also irritates the airways and etches surfaces.

SO2 equivalent
The quantitative expression of the acidification potential related to the main gas SO2. Among the substances contributing to the SO2 equivalents are the pollutants NOx, HCl, HF, NH3, and H2S.

Greenhouse gas (GHG)
Greenhouse gases are gaseous emissions that contribute to the greenhouse effect. These belong to the relevant environmental indicators and may be aggregated to the global warming potential. Important GHG are CO2, CH4, N2O as well as SF6, PFC, and HFC (so called Kyoto gases).

Greenhouse factor
Factor representing the contribution of a greenhouse gas to the global greenhouse effect. It addresses the differing impact characteristics of the various GHGs when calculating the global warming potential.

Global warming potential (GWP)
The global warming potential is the mass-related equivalent of the contribution of a greenhouse gas to the greenhouse effect, relative to CO2 and thus expressed as CO2 equivalents. Due to the impact characteristics and the different atmospheric residence times of the various GHGs, the GWP is calculated as a time integral.

TOPP
TOPP is short for "tropospheric ozone precursor potential", and a quantitative expression of the tropospheric ozone formation potential. It is calculated from the relative ozone formation rate of the atmospheric pollutants CO, NMVOC, NOx, and CH4 (which is also a greenhouse gas). The higher the amount of tropospheric ozone precursor equivalents, the greater the possibility for summer's smog.

Acidification potential
Aggregation of acidifying atmospheric pollutants, expressed in mass-related SO2 equivalents. This is one of the most important environmental indicators.

upstream process chain, upstream product
The upstream process chain of a process is the process chain which produces the inputs of that process. The upstream process chain consists of upstream processes, while the intermediate products are called upstream products.