Add embodied emissions to storage

[jnioche]

we only have them for EC2 instances currently

CCF only does them for compute usage

[jnioche]

Understanding the Carbon Footprint of Storage Media: A Critical Review of Embodied Emissions in Hard Disk Drives

13.3 kg CO₂ per drive for HDD

They mention previous research by

Tannu and Nair [26] concluded that,
on average, SSDs have about eight times higher embodied
environmental costs than HDDs of identical capacity—320 vs.
40 kg of CO2e, respectively, for 1TB of storage capacity. These
estimates were derived by averaging the embodied emissions
from 94 LCA/PCF reports from eight different SSDs vendors,
and 24 LCA/PCF reports from four HDDs vendors. The authors
introduced the Storage Embodied Factor (SEF), defined as the
ratio of embodied impact (kg CO2e) to storage capacity (GB).
Their evaluations indicated an average SEF value of 0.16 kg
CO2e per GB for SSDs and a SEF of 0.02 for HDDs.

[26] S. Tannu and P. J. Nair. 2023. The Dirty Secret of SSDs: Embodied
Carbon. SIGENERGY Energy Inform. Rev. 3, vol. 3, pp. 4-9, Oct. 2023.
doi: 10.1145/3630614.3630616.

https://arxiv.org/pdf/2207.10793

so assuming a lifetime of 6 years (52560 hours / 72 months) we would get :

• HDD -> 20g / 52560 = 0.00038g per hour per GB ?
• SSD -> 160g / 52560 = 0.00304 per hour per GB ?

For 43800 hours (5 years)

• HDD = 0.000456621 g / hour / GB
• SSD = 0.00365296803 g / hour / GB

[jnioche]

https://dataviz.boavizta.org/terminalimpact

gives 109.0 kgCO2eq
0.000397 kg SB eq. for ADP
for an external ssd

15.8 kgCO2eq / 0.002340 kg SB eq.
for an external hdd

Green Cloud Computing, 2021
is given as a source of data in https://doc.api.boavizta.org/Explanations/components/ssd/

not sure what the average size or lifetime of the disks are supposed to be.

using the BoaviztAPI

'https://api.boavizta.org/v1/peripheral/external_ssd?archetype=external-ssd-default&verbose=true&duration=1&criteria=gwp&criteria=adp&criteria=pe'

based on a lifetime of 43800 hours (5 years)

externalSSD for 1 hour -> 0.002489 kgCO2eq
externalHDD for 1 hour -> 0.0003607 kgCO2eq

but not clear what size is given by default

EC2 instances

SSD

0.00109375 g per GB for a instance_type=c3.8xlarge with 640GB SSD (0.0007kg embodied for 1 hour)
0.00088888 g per GB for a c5d.metal with 3600GB SSD (0.0032kg embodied for 1 hour)
0.00081578947 g per GB for a c6gd.metal with 3800GB SSD

HDD

0.00004229166 g per GB for d3en.12xlarge wth 336000 GB (0.01421kg embodied for 1 hour)

[jnioche]

Tailpipe

0.056 kg per GB over the lifetime of the drive for SSD
0.0022kg per GB for HDD

so for a 3800 GB SSD, the lifetime embodied emissions are 212.8 KG CO2eq

See also https://tailpipe.ai/methodology/embodied-emissions-methodology-manufacture/

They distinguish onboard storage from NAS. For the latter they give a per GB figure of 0.0013 kgCO2e/GB.

The embodied SSD figure of 0.056 kgCO2e/GB is taken from this paper: Embodied Carbon Footprint of 3D NAND Memories, 2025.

The embodied HDD figure of 0.0022 kgCO2e/GB is an average of four Seagate HDD LCAs.