Key Idea: Linear ends in disposal. Circular ends in a return, and resources are continuously repurposed. The tight loops — maintain, reuse, repair — keep far more than recycling, which keeps only the material. Recycling a linear product is still linear. Four strategies design waste out: longevity, upgradability, disassembly, dematerialization — longevity first. Biodegradable is for what cannot be collected. And you cannot run a closed material loop on an open energy loop.
Paper 1 — multiple choice
- Rank the recovery loops by value kept
- Match a decision to one of the four waste strategies
- Say where a biodegradable material is the right choice
- Identify the condition that makes biomass renewable
Paper 2 — analysing a product
- Compare a linear and a circular approach to a product
- Explain how a product could be designed to eliminate waste
- Explain how a product could be designed for recovery
- Explain why a circular economy relies on renewable energy
Carried into the design project
- Criterion D — fixings, materials and a route to recovery
- Disassembly is a testable criterion: time, tools, streams
- Criterion E — what genuinely happens at the end of life
Recycling is the answer students give first and the loop that preserves least. Learning the order is most of this topic.
| Loop | What it keeps | What the design must provide |
|---|---|---|
| Maintain | Everything — shape, assembly, material, embodied energy | Serviceable design and a user who knows how |
| Reuse | Everything except the first owner | A product that survives a first life intact, and a resale route |
| Repair | The assembly; only worn parts change | Standard fixings, a procedure, and spares for the whole life |
| Remanufacture | The parts, rebuilt to as-new | Parts that separate, clean and refit — and a product worth the labour |
| Recycle | The material only | Separable, marked, single materials in worthwhile quantities |
A product designed to be sold ends in a bin. A product designed to be returned ends in a loop. Every recovery route needs two things: a design decision taken years earlier, and a business with a reason to want it back.
The linear chain, the return that replaces disposal, and why the tight loops are worth far more.
🔒 Interactive diagram
Explore the labelled diagram, charts and maps for this topic in study mode.
| Order | Strategy | What defeats it |
|---|---|---|
| 1 | Longevity — wear parts replaceable, surfaces that age well, spares stocked | One unobtainable part |
| 2 | Disassembly — screws not glue, one material per part, marked, reachable | A laminate, or a glued-in battery |
| 3 | Upgradability — the fast-moving part on its own module, a stable interface | A proprietary connector changed each model |
| 4 | Dematerialization — less mass, fewer parts, concentrate and refill | Thinning until it breaks sooner |
Important: Equating circular with recycling. It is the last and weakest loop. Treating biodegradable as a general upgrade. It is for products that are used once, spread out or contaminated — never a durable product. Listing renewable sources instead of making the argument: circulating material costs energy, so a fossil-powered loop can be worse than making new.
Each route with what it keeps, what the product needs, and what stops it.
🔒 Interactive diagram
Explore the labelled diagram, charts and maps for this topic in study mode.
Explain how a washing machine could be designed and sold so that products, components and materials are recovered.
🔒 Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.
A food chain replaces plastic cutlery with compostable cutlery. Evaluate this against a circular-economy model.
🔒 Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.
What is the structural difference between linear and circular?
Why is recycling the last loop?
Why does longevity come first among the waste strategies?
Where do biodegradable materials genuinely help?
What can take-back legislation not do?
Why does a circular economy rely on renewable energy?
Exam tips
- Linear ends in disposal; circular ends in a return.
- Rank the loops: maintain, reuse, repair, remanufacture, then recycle.
- Longevity first among the waste strategies, with a reason.
- Make disassembly testable: time, tools, material streams.
- Biodegradable is for what cannot be collected, and it is a condition.
- Closed material loop, open energy loop — say the line.