6. Eligibility, Selection, and Inclusion Logic

6.1 Grid Area Eligibility

Where a usable published source covers a grid area and that area supplies at least one supported cloud region, or where a supported cloud region is expected to draw on it, the methodology configures that grid area. A grid area's boundary follows the boundary its publishing body uses, which for most countries is the national grid, for the United States is the balancing authority, for a market split into bidding zones is the bidding zone, for the United Kingdom is the distribution region, and for a country running more than one separate network is each network in turn.

6.2 Source Selection

For each grid area, Greenpixie selects one source, preferring the grid operator for that area, then a modelled national generation dataset, then a national inventory or regulatory figure for the country. A usable source covers the whole of the grid area's generation and states the basis on which its figures are compiled.

A modelled national generation dataset states for each country whether it measures the monthly generation mix or models it. Greenpixie takes a monthly series where its publisher measures the mix. Where the publisher models the mix, the yearly series for that country is taken instead.

Section 7.3 sets out the source and the approach used in the United States, the United Kingdom, Europe and Australia. The full table of which source serves which grid area is proprietary.

6.3 Cloud Region Mapping

Greenpixie matches each cloud region to the grid area or areas that supply it, with a weight for each. A cloud region outside the United States is matched to a single grid area, at a weight of 1.0. A cloud region in the United States is matched to the balancing authorities serving the counties it occupies, each weighted by its contribution to the supply of the cloud region's location. Three United States cloud regions instead take an equal weight for each county they occupy.

Where a cloud region cannot be matched to a grid area, that cloud region takes the global mean, being the unweighted average of every configured cloud region's intensity. Section 6.2 sets out when no grid area is configured for a country. An average of that kind removes the regional variation a specific grid area would carry. The resulting factor can be higher or lower than the figure a specific grid area would have produced.

6.4 Fuel Coverage and Exclusion

A grid area's published generation mix can include a fuel category that the grid area's emission factor table does not cover, most often an unlabelled category the source names only as other, or a storage category the source does not break down. Where a fuel category is not covered, the methodology excludes that generation and re-normalises the remaining fuel shares across the generation the factor table does cover. That excluded share carries the average intensity of the fuels the table covers. The direction of the resulting error depends on whether the excluded generation is more or less carbon intensive than the fuels the table covers. The source does not publish that intensity.