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intro_hdd [2026/02/03 09:27] – removed - external edit (Unknown date) 127.0.0.1intro_hdd [2026/05/19 12:08] (current) – louise
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 +# HDD
 +
 +## System Definition - Goal and scope
 +
 +  * HDD = Hard Disk Drive
 +  * Storage device that uses magnetic storage to save, store and retrieve data
 +
 +### Definition
 +#### What is it used for?
 +  * Save, store and retrieve data
 +  * It is permanent storage, unlike volatile memory like RAM.
 +  * Can be used in desktops, laptops, servers or for external storage.
 +
 +#### Are there different types/technologies?
 +
 +Interface:
 +  * SATA = Serial ATA
 +  * PATA = Parallel ATA
 +  * SCSI = Small Computer System Interface
 +
 +Form factor:
 +  * 2.5 inch
 +  * 3.4 inch
 +
 +#### If different types, what are the differences in terms of materials, process, use consumption?
 +#### Is there a generic component that represents a family of components?
 +#### How many sub-parts does the system consist of?
 +
 +### Perimeter
 +#### What is included?
 +#### What is excluded?
 +
 +### Functional unit and reference flows
 +#### What is the functional unit?
 +#### What are the reference flows?
 +
 +
 +## Life Cycle - Inventory
 +=> Goal: Define state of the art on life cycle stages to be considered.
 +
 +### Database and tools
 +#### What are the already existing data (dataset, parametric model, paper, etc.)?
 +
 +### Raw materials
 +=> Goal: List the technical information needed for the LCI.
 +
 +#### What is it made of?
 +#### Who are the main mining? Where are they located?
 +#### Is there mining processes information available?
 +
 +
 +### Manufacturing
 +=> Goal: List the technical information needed for the LCI.
 +
 +//For each system sub-part://
 +#### What are the manufacturing processes?
 +#### What are the assembly processes?
 +#### For each process, what is the energy consumption?
 +#### For each process, what are the inputs (water, chemicals, etc.) ?
 +#### For each process, what is the yield? Are they co-products and/or losses?
 +
 +//TBR//
 +
 +An HDD is composed of the following elements:
 +
 +Platters:
 +  * One or more
 +  * Double-sided
 +  * Glass substrates, coated with magnetic material
 +  * They are spinning, thanks to the motor.
 +
 +Motor:
 +  * Spindle with motor
 +
 +Read-write heads:
 +  * Positioned by actuators
 +  * It is flying 3 nm above the disk surface
 +
 +Supporting electronics
 +
 +
 +#### How the “main” manufacturers can be characterized: by the number of components manufactured, the market share (€), other?
 +#### Who are the main manufacturers?
 +3 main manufacturers:
 +  * Seagate
 +  * Western Digital
 +  * Toshiba
 +#### Where are they located?
 +
 +### Distribution and packaging
 +=> Goal: List the technical information needed for the LCI.
 +
 +#### What are the packaging? Made of which materials?
 +#### Which are the transport modes?
 +#### What are the transport distances?
 +
 +### Use
 +=> Goal: List the technical information needed for the LCI.
 +
 +#### What is the service lifespan? (durée d'utilisation)
 +#### Is there a reparation factor?
 +#### Is there sub-parts replacement?
 +
 +#### Where is it used?
 +#### Who are the users?
 +#### Which + how much energy does it need?
 +#### Is there emissions from use?
 +
 +### End of life
 +=> Goal: List the technical information needed for the LCI.
 +
 +#### What is the lifetime? (durée de vie)
 +#### Is it different from lifespan and why?
 +#### Is it refurbished? + Where?
 +#### Is it recyclable? Can it be dismantled? Which material can be separated? + Where and how?
 +#### Is it incinerated with energy recovery? Just incinerated? Buried? + Where?
 +#### Which part of waste can be considered as mismanaged (neither recycled, nor incinerated, nor buried)?
 +
 +
 +## State of the art
 +=> Goal: Define state of the art on environmental impacts. 
 +
 +For all the existing works, define:
 +  * Methodology (LCA/GHG, env. indicators, etc.)
 +  * Types of technologies covered (system definition)
 +  * Life cycle stages covered
 +  * Flux included in the scope
 +  * Main results (hot spots, orders of magnitude, etc.)
 +  * Limitations
 +
 +
 +## Bibliography
 +=> Goal: Source every data we cited previously
 +
 +### List of our sources
 +### Data origin: bibliographic source / consortium hypothesis / expert opinion - required if a Data Quality Rating (DQR) must be completed
 +
 +
 +
 +## Next steps
 +=> Goal: List challenges and clarify priority areas for action
 +
 +### What do we know we don't know?
 +### What are the identified challenges?
 +### What paths/ideas should be explored?
 +