Block Storage footprint calculation

This page includes the specificities of the environmental footprint calculation for Block Storage.

Calculation aspects

The total estimated impact of Block Storage volumes is calculated by integrating the:

• Dedicated manufacturing impact - Related to the physical servers hosting the storage volumes.
• Related manufacturing impact - The impact of the tools used to manage the Block Storage offers: control plane, monitoring, internal load balancers, and others.
• Energy usage impact - The average electricity consumption of storage servers and their energy efficiency and of the tools used to manage the Block Storage offers.

Ratio per storage volume

To allocate the impact of a Block Storage volume, we apply the unit resulting from the RCP allocation rule to all calculation steps, the bls_ratio:

bls_ratio = VOLsto/VolstoPool

• VOLsto - represents the reserved volume per user. In Block Storage, your data is replicated three times on multiple nodes to guarantee availability, so the VOLsto is applied with factor of 3 to account for replication.
• VolstoPool - represents the total storage volume reserved for Block Storage.

In the example below we consider a VOLsto of 600 GB and a VolstoPool of 1000 GB.

bls_ratio = 600/1000 = 0,6

Manufacturing impact

The calculation of the manufacturing impact of Block Storage volumes is based on:

• The manufacturing impact of servers that host user storage
• The manufacturing impact of servers used by the Scaleway Block Storage team to manage the service - on both the Control and Data planes

The calculation is the same used for measuring the impact of manufacturing for Bare Metal servers, but for Block Storage we also apply the bls_ratio to break the impact down to only the allocated volumes.

Calculation example

For the example below, we consider a single server with a lifespan of 6 years (52 560 hours) and power of 110w. We measure the impact of 100 hours and consider through Boavizta estimates that the impact of the manufacturing of this server is 850 kgCo2e. Also considering a bls_ratio of 0,6, we make the following calculation:

VolumeManufacturingImpact = (100 / 52560) * 850 * 0,6 = 0,97 kgCO2e

In the example, the dedicated manufacturing impact of a 600 GB usage for 100 hours is 0,97 kgCo2e.

Usage impact

The calculation of the usage impact of Block Storage volumes is based on:

• Impact of electricity consumption of servers that host user storage
• Impact of electricity consumption of infrastructure and service management servers by the Scaleway Block Storage team to run the Block Storage service. In this case we consider both the Control and Data planes.

To calculate the impact of a kwh, we consider the French energy mix and the datacenter's PUE.

In the example below, they are O,065kgCo2e/kwh and 1,16, respectively. Considering an electrical consumption of 600wh, 100 hours of usage, and a bls_ratio of 0,6, the total usage impact comes down to:

UsageImpact = (0,600 x 0,065) * 100 * 0,6 = 2,34 kgCo2e

In the example, the usage impact of a 600 GB usage for 100 hours is 2,34 kgCo2e.