The life cycle of a product

List the stages of a product lifecycle and describe each one using the example of a cotton T-shirt.

Explain what life cycle assessment (LCA) is and what questions it tries to answer about a product.

Explain what the carbon footprint of a product is: what it measures and in which stages of its lifecycle it is mainly generated.

Explain with an example why 'throwing something in the bin' is not the true end of its lifecycle.

In many electronic devices, a significant part of the environmental impact occurs before you buy them. Explain which stages of the lifecycle this statement refers to and give reasons why.

A pair of jeans requires a huge amount of water throughout its lifecycle. Identify which stages of its lifecycle involve water and propose two specific measures to reduce that consumption.

Compare the lifecycle of a returnable glass bottle with that of a single-use plastic bottle: state in which stages they differ most and why.

Explain what ecodesign is by looking at the entire lifecycle: name a design decision that improves each stage (materials, manufacturing, transport, use, and end of life) of a bottle.

A supermarket claims: "Our new kraft paper bags are 100% eco-friendly compared to plastic ones." To verify this, they provide you with this simplified excerpt from a Life Cycle Assessment (per bag):

• Paper bag: Carbon footprint: 0,09 kg CO₂-eq; Water consumption: 3,8 L; Estimated average lifespan: 1,5 uses; End of life: 80% recycled or composted.

• Plastic bag (HDPE): Carbon footprint: 0,03 kg CO₂-eq; Water consumption: 0,2 L; Estimated average lifespan: 3 uses; End of life: 20% recycled, 80% landfill/environmental dispersion.

1. a) Refute the advertising claim by calculating the CO₂ emissions and water consumption per 100 shopping trips using both options.
2. b) Justify what environmental dilemma the choice between the two raises: in which life cycle phases is paper more harmful, and in which is plastic clearly worse?

A wireless headphone manufacturer has soldered the lithium battery directly to the motherboard and integrated firmware that locks the device after 400 charging cycles, claiming "safety reasons."

1. a) Identify the two types of obsolescence present (planned hardware and software obsolescence) and describe how they artificially alter the "use" and "end-of-life" phases in the product's life cycle.
2. b) Design three technical modifications (in mechanical joints, component accessibility, and software) so that the product can be repaired by the user and its durability tripled.

A city is debating two 2-million-euro budget options to manage its packaging waste:

• Option A: Automate the recycling plant to increase the sorting of single-use plastics.

• Option B: Implement a Deposit, Return, and Refund System (DRS) for standardized reusable glass and plastic packaging for local commerce.

1. a) Supported by the life cycle stages (raw material extraction, melting/recycling energy, and material degradation in each cycle), justify why recycling (Option A) does not avoid intensive resource consumption compared to reuse (Option B).
2. b) Identify what new logistical and hygienic stage must be incorporated into the packaging life cycle of Option B for the system to operate safely and efficiently.

You are tasked with redesigning a classroom chair (metal frame, plastic seat and backrest) applying the principles of the circular economy and end-of-life ("Cradle to Cradle").

1. a) Specify which mechanical joining solutions you must choose and which you must strictly reject (such as permanent welds in mixed areas, blind rivets, or contact adhesives) to allow disassembly to be carried out at the school itself using standard tools in under 5 minutes.
2. b) Design the reverse material flow diagram: indicate the technical path each component (steel, thermoplastic) will follow once the chair is retired (primary recycling, remanufacturing, or modular replacement) and how to ensure that no item ends up in a landfill.