5. Inputs and Evidence Sources

The methodology draws on the following categories of inputs.

5.1 Grid Operator and Market Data

Generation and carbon intensity data published by grid operators, at hourly or sub-hourly resolution. These include the United States Energy Information Administration's Form EIA-930 balancing authority operations data, the actual generation per production type published on the Transparency Platform of the European Network of Transmission System Operators for Electricity (ENTSO-E), the National Energy System Operator's Carbon Intensity API, the éCO2mix national generation datasets of the French transmission system operator RTE, and the Australian Energy Market Operator's Carbon Dioxide Equivalent Intensity Index and Wholesale Electricity Market facility data.

5.2 Modelled National Generation Data

Where no grid operator publishes at hourly resolution for a country, the methodology takes national electricity generation by fuel from a published modelled national dataset, at monthly or yearly resolution.

5.3 National Inventory and Regulatory Factors

Emission factors published by national greenhouse gas inventories and by regulators, being the Australian National Greenhouse Accounts Factors from the Department of Climate Change, Energy, the Environment and Water, the electricity intensity tables published with Canada's Official Greenhouse Gas Inventory by Environment and Climate Change Canada, and the subregion emission factors of the United States Environmental Protection Agency's Emissions and Generation Resource Integrated Database (eGRID). National factors are also taken from the Italian Institute for Environmental Protection and Research (ISPRA), from the Sustainable Energy Authority of Ireland, from the National Centre for Emissions Management (KOBiZE) in Poland for lignite, from the Ministry of Energy and Mineral Resources in Indonesia, from the national emission factor table published in South Korea, from the Ministry for the Environment in New Zealand, and from CLP Power in Hong Kong. For Greek lignite, Greenpixie builds the factor from European Union Emissions Trading System data, as compiled and published by a third party.

5.4 Lifecycle and Upstream Emission Factors

Factors covering the part of the generation lifecycle that a combustion figure excludes, drawn from the Intergovernmental Panel on Climate Change through its Fifth Assessment Report, its Special Report on Renewable Energy Sources and Climate Change Mitigation and its 2006 Guidelines for National Greenhouse Gas Inventories.

Where the source a grid area takes does not include Upstream and Downstream Emissions, Greenpixie adds them to the total Grid Carbon Intensity, calculated from published life cycle assessment studies and published energy and emissions statistics. For some grid areas the figure added is a country-level average of the upstream and downstream intensity of each generating technology, weighted by that technology's share of generation.

5.5 Transmission and Distribution Loss Data

Published loss statistics for each grid area, being the World Bank's electric power transmission and distribution losses indicator and the grid gross loss figures the United States Environmental Protection Agency publishes with eGRID. Where a national inventory publishes its own loss component, Greenpixie takes that component as the loss factor, in place of a separate statistic.

5.6 Cloud Region Location Data

Cloud provider documentation and published price catalogues identifying where each cloud region is located. In the United States, Greenpixie resolves a published place name to the county containing it, using the United States Census Bureau's place to county relationship file.

5.7 Water Stress Data

Baseline water stress rankings from Aqueduct 4.0, published by the World Resources Institute.

5.8 Cloud Provider Efficiency Disclosure

Power usage effectiveness published by each cloud provider for its own estates, being the AWS regional sustainability data and its published PUE methodology, the Azure data centre efficiency page, and the Google Cloud data centre efficiency history. Each cloud provider states the scope its figure covers and the period the figure was measured over. Alongside each value, Greenpixie records both.

5.9 Regulatory and Standards Sources

The methodology references the GHG Protocol Corporate Standard, the GHG Protocol Scope 2 Guidance, the GHG Protocol Corporate Value Chain (Scope 3) Standard, ISO 14064-1, and ISO/IEC 30134-2 for the definition of power usage effectiveness.