3. Definitions

Balancing Authority. The entity responsible for maintaining the balance of electricity supply and demand within a defined area of the United States transmission system. Hourly generation data for that country is published per authority.

Cloud Provider. A company that offers cloud computing services and solutions to businesses and individuals. In this methodology, the term refers to AWS, Azure, and Google Cloud. Distinct from the grid operator that publishes the generation data for the area a cloud region draws its electricity from.

Cloud Region. A named geographic location in which a cloud provider operates data centres, and the unit by which cloud usage is billed and matched to an electricity grid.

CO₂e. Carbon dioxide equivalent. A metric that expresses the global warming potential of various greenhouse gases as the equivalent amount of carbon dioxide.

Combustion Emissions. The greenhouse gases released at a generating station in burning fuel to produce electricity. Reported as Scope 2 by a consumer applying the location-based method.

Electricity Grid. The interconnected network for delivering electricity from producers to consumers, consisting of generating stations, transmission lines, and distribution lines.

Emission Factor. The quantity of greenhouse gases released per unit of electricity generated by a given fuel or generating technology, expressed in CO₂e terms.

Fuel Mix. The share of a grid area's electricity generation contributed by each fuel or generating technology over a given period.

Grid Area. The unit at which this methodology calculates carbon intensity, being a single electricity system or market area such as a national grid, a balancing authority, or a separate island system.

Grid Carbon Intensity. The average emissions produced per unit of electricity consumed from a given electricity grid, varying by region and time. Abbreviated as GCI.

Grid Operator. The body that operates an electricity grid or market and publishes its generation data, whether a transmission system grid operator, a market operator or a balancing authority. Distinct from the cloud provider that buys electricity from the grid.

kWh. Kilowatt-hour. The unit of energy consumption used to calculate associated GHG emissions based on the carbon intensity of the energy source.

Location-Based Method. A method for calculating carbon emissions based on the average emissions intensity of the electricity grid on which energy consumption occurs.

Power Usage Effectiveness. A ratio expressing the energy efficiency of a data centre, defined as total facility energy divided by the energy consumed by its IT equipment. Abbreviated as PUE.

Provenance Label. An internal record Greenpixie keeps against every published hour, stating how that hour's intensity was produced, distinguishing measured source data, a published forecast, a figure carried forward, a filled value, and a fixed published figure applied across a period.

Transmission and Distribution Losses. The electricity lost between the generating station and the point of consumption, and the emissions attributable to generating that electricity. Reported as Scope 3 Category 3 by a consumer.

Upstream and Downstream Emissions. The greenhouse gases released across the lifecycle of electricity generation other than at combustion, covering fuel extraction, processing and transport, and the construction and decommissioning of generating plant. Reported as Scope 3 by a consumer.

Water Stress. The ratio of water demand to renewable supply in a given area, published as a ranked category by Aqueduct 4.0. The area taken for a cloud region is the province or administrative region containing the city its data centres are located in.