2. Scope and Applicability

2.1 In Scope

The methodology applies to the following:

• Supported cloud providers. The regions of Amazon Web Services, Microsoft Azure, and Google Cloud, including the government and sovereign regions each provider operates.
• Price inputs. The providers' published on-demand prices for services priced on a per-region basis, including compute, storage, database, and the remaining catalogue services that carry a regional price.
• Environmental inputs. Hourly grid carbon intensity factors for the grid serving each region, produced by GPX Grid, and baseline water stress figures published in Aqueduct 4.0.
• Carbon grade. The letter grade assigned from the region's average grid carbon intensity, published for every region for which a grid carbon intensity figure is available.
• Water stress category. The baseline water stress category of the Aqueduct area covering the region's location, published for every region Aqueduct covers.
• Band boundaries. The boundaries of each set of bands in a data version, published with the scores that version produced.
• Cost grade. The grade assigned from the region's relative cost percentage, published for every region that prices a sufficient share of the comparison basket.
• Availability grade. The grade assigned from the region's service availability percentage, published for every region whose prices appear in the price list covering the rest of its provider's estate.

2.2 Out of Scope

The following are not covered by this methodology:

• Network and data transfer prices. A transfer price attaches to a route between two endpoints and not to a single region, so there is no defensible way to credit it to one region's score. No part of any score accounts for network pricing indirectly.
• Prices that depend on a commitment or on spare capacity, including reservations, savings plans, committed use discounts, and spot or pre-emptible prices.
• Privately negotiated pricing, which Greenpixie does not hold for this purpose.
• Customer usage and spend, which form no part of any of the four scores.
• Regions whose prices the provider publishes separately from the list covering the rest of its estate. They receive no pricing score and no availability score, and they keep their carbon grade and water stress category.
• The emissions of a customer's workload. The carbon grade describes the intensity of the grid a region draws from, and the emissions of a workload running in that region are calculated per unit of cloud usage under the Greenpixie Methodology for Cloud Emission Measurement.
• The water a customer's workload consumes. The water stress category describes the stress on water supply in the area a region sits in, and the water consumed in cooling a workload and in generating the electricity it draws is calculated under the Greenpixie Methodology for Cloud Emission Measurement.

2.3 Evaluation Boundary

The evaluation boundary encompasses the provider's published price catalogue for each region, the electricity grid that supplies the region, and the Aqueduct area containing the region's location. Every price comparison is made within one provider and within one data version, and the boundary of the pricing and availability assessment is the published catalogue and not a customer's bill. Those two scores describe what a region charges for the things it sells, and what it sells, weighted by nothing other than the composition of the comparison basket described in Section 6.

The carbon grade and the water stress category have a different boundary. Both describe the location a region occupies, being the grid that supplies its electricity and the Aqueduct area that contains it. The carbon grade uses location-based grid-average factors, so it does not account for contractual instruments such as power purchase agreements or renewable energy certificates. Neither score reflects the efficiency of the data centre, the provider's energy or water procurement, or anything a workload does inside it.