Fairphone
A smartphone you're meant to open up, not send back.
Read case study →Take, make, use, throw away. That sequence is so normal it is easy to miss how recent and how strange it is, and the circular economy is an attempt to design our way back out of it. The central insight is that waste is not an unfortunate by-product of making things. It is a design decision, taken at the drawing stage, by someone who chose a glued seam over a screwed one or seven mixed polymers over one.
This topic sits in Topic C rather than on a recycling poster because it puts the responsibility in the right place. Recycling asks the consumer to fix a problem after the fact, usually badly and usually too late. A circular approach asks the designer to prevent it, which turns material choices, joining methods and disassembly into environmental decisions rather than purely technical ones. That connects straight to C4.1, and it makes for strong Paper 2 answers, because a question about waste answered with specific design decisions will always beat one answered with good intentions.
Students must be able toCompare and contrast a linear approach and the circular economy.
The linear economy is characterised by the phrase "take, make, consume, dispose." Resources are extracted from the environment, processed into products, consumed, and then discarded (sent to landfill or incineration) at the end of their life. This model relies on non-renewable energy and generates large volumes of waste. It treats resources as unlimited and end-of-life as inevitable.
The circular economy is a closed-loop system where resources are continuously repurposed, mimicking the closed nutrient cycles of biological ecosystems. Kirchherr et al. (2017) define it as an economic system that replaces the "end-of-life" concept with reducing, reusing, recycling, and recovering materials in production, distribution, and consumption processes. It relies on renewable energy, and examples of materials in circular use include PET beverage bottles (collected, shredded, and remanufactured into new bottles or textiles) and paper and cardboard (continuously recycled into new paper products).
Key comparison:
- Linear: focuses on production efficiency, market consumption, and maximising short-term profit; generates high levels of waste and significant cumulative environmental impact; relies on non-renewable energy and virgin raw material inputs
- Circular: focuses on reuse, recycle, and recover; aims to eliminate waste at the design stage; relies on renewable energy; treats end-of-life materials as inputs for new production cycles rather than disposables
Policy context: In 2020, the European Commission adopted a Circular Economy Action Plan as part of the European Green Deal, targeting climate neutrality (net-zero greenhouse gas emissions) by 2050 and a halt to biodiversity loss by 2025. China uses five-year plan cycles to review and revise its sustainability goals and circular economy targets, embedding them into national economic planning.
Design
Manufacture
Distribution
Sale
Maintenance
Reuse
Refurbish
Recycle
Resource Recovery
Hover, focus or tap a stage to see what actually happens there.
Students must be able toDiscuss how designers can design products in ways that eliminate waste and pollution, including designing for longevity, upgradability, disassembly and dematerialisation.
Tackling waste early, at the design stage itself, is far more effective than trying to manage it after a product exists, and this is the thinking behind design-for-manufacture (DFM) guidelines. Designers use a family of "design-for" strategies to eliminate waste and pollution across the full product life cycle:
- Design for materials: select appropriate, low-impact materials; reduce toxic substances, hazardous waste, and polluting emissions; specify single-component materials for moulding (avoiding mixed-material assemblies that cannot be separated for recycling); and mark recyclable materials using resin identification codes for later identification at recycling facilities.
- Design for process: reduce energy consumption and the number of manufacturing steps; minimise production waste, emissions, and the need for secondary operations such as plating, painting, and welding, which add chemical inputs and energy.
- Design for assembly: analyse components and sub-assemblies to reduce the total part count and the variety of fasteners and tool types required; snap-fit and press-fit joints replace adhesive bonds and screws, making products easier to assemble initially and easier to disassemble for repair or recycling at end of life.
- Design for longevity: create longer-lasting products through repairability (standardised spare parts, accessible fixings), upgradability (modular components the user can replace independently), high-quality materials that do not degrade prematurely, timeless aesthetics that do not become unfashionable, and emotional connection that makes users unwilling to discard a product while it still functions. A product that lasts 10 years instead of 2 generates far less waste across its user base.
Dematerialisation describes a steady drop in how much energy or material it takes to deliver the same product or service over time. Examples include email replacing fax and physical surface mail, miniaturisation of electronics, and streaming services replacing physical discs. Dematerialisation directly supports the circular economy by reducing resource inputs per unit of value delivered.
Jevons' Paradox (rebound effect): In 1865, English economist William Stanley Jevons observed that more efficient steam engines led to increased total coal consumption, not a reduction. Cheaper, more effective steam power expanded into new applications (more factories, trains, ships), so total coal use rose even though each engine used less fuel per unit of work. Designers must be aware that efficiency improvements alone cannot be assumed to reduce total resource consumption. If a more fuel-efficient car makes driving cheaper, users may drive more often or further, partially or fully offsetting the gain. Systemic responses and behavioural design (e.g., full-load prompts on appliances) are needed alongside dematerialisation.
Discussion
Is recycling actually circular, or just a slower line?
Recycling a PET bottle isn't really a closed loop. Every recycling pass loses some material quality (a process called downcycling), the collection, sorting and reprocessing steps consume energy and water of their own, and most plastic labelled "recyclable" is only recycled once or twice, if at all, before it's landfilled or incinerated anyway. A genuine closed loop, glass or aluminium recycled indefinitely without quality loss, is the exception, not the rule.
Does a product that gets recycled once, then landfilled, belong anywhere near the word "circular"? Where would you draw the line between a true circular economy and a linear economy that just has one extra, partially effective step bolted onto the end of it?
Students must be able toDiscuss why biodegradable materials are a preferred material in a circular economy model.
Biodegradable materials break down through natural biological processes (decomposed by microorganisms) into water, minerals, and organic matter. This end-of-life pathway is fundamentally different from conventional synthetic plastics, which persist in the environment for hundreds of years, fragmenting into microplastics that enter food chains and waterways.
Why biodegradable materials are preferred in a circular economy:
- Provide soil nutrients: when biodegradable products compost, they return organic matter and minerals to the soil, supporting agricultural productivity rather than depleting it
- Reduce landfill waste: biodegradable materials that complete their biological cycle do not accumulate in landfills, freeing capacity and reducing methane generation from anaerobic decomposition of buried organic material
- Lower greenhouse gas emissions: compared to incineration or landfill of persistent plastics, biodegradation (especially aerobic composting) produces lower net greenhouse gas emissions over the material's lifetime
- Regulatory compliance: many jurisdictions are introducing bans or levies on single-use plastics and non-biodegradable packaging; using biodegradable alternatives helps companies avoid fines, comply with regulations, and access markets that require it
- Closed biological cycle: in the circular economy framework, biodegradable materials participate in the biological cycle: they safely re-enter natural systems after use rather than requiring industrial recycling or persisting as pollution
Limitations: Not all biodegradable materials break down under ordinary conditions. Some require industrial composting facilities (specific temperature, humidity, and microbial conditions) that may not exist in the disposal location. Designers must specify the correct end-of-life pathway and ensure it is accessible to users: labelling alone is insufficient if the infrastructure does not exist.
Students must be able toDiscuss how designers can consider the recovery and restoration of products, components and materials through take-back legislation, reuse, repair, recondition or recycling.
Circular economy thinking requires designers to plan the entire product life cycle (including what happens to the product, its components, and its materials when the user is finished with it). Recovery and restoration form the closing loop of circular design:
- Reuse: the product is used again in its original form, by the same or a different user, without any manufacturing processing. Example: glass milk bottles collected, cleaned, and refilled. Requires standardised, durable packaging or product forms.
- Repair: individual components are replaced or fixed to return a product to working order, extending its useful life. Designers support repairability through accessible fixings, available spare parts, and standardised components. The Right to Repair movement advocates for legislation requiring manufacturers to provide spare parts and repair documentation.
- Recondition (refurbish): products are cleaned, tested, and restored to a like-new condition, often with replacement of worn components. Reconditioning typically requires more intervention than repair but less resource input than manufacturing new. Example: remanufactured printer cartridges, refurbished electronics.
- Recycling: materials are recovered and processed into raw material inputs for new production. To facilitate recycling, designers use the resin identification coding system (numbers 1–7 inside a triangle of chasing arrows): 1 PET, 2 HDPE, 3 PVC, 4 LDPE, 5 PP, 6 PS, 7 OTHER. Single-material components and clear labelling enable efficient sorting at recycling facilities, avoiding costly spectroscopic analysis. Mixing plastic types (e.g., a PET bottle with a PVC label) contaminates recycling streams.
Take-back legislation places legal responsibility on manufacturers to recover products at end of life. Examples include the EU Waste Electrical and Electronic Equipment (WEEE) Directive (requiring manufacturers to fund and organise collection and recycling of electronics) and extended producer responsibility (EPR) schemes for packaging. Take-back legislation creates an economic incentive for designers to design for disassembly and recyclability: the manufacturer pays for end-of-life handling, so reducing that cost requires designing products that are cheap to recover.
Key concept
Extended Producer Responsibility (EPR)
Extended Producer Responsibility is a policy principle that makes the manufacturer of a product financially and physically responsible for that product once the consumer is finished with it, rather than leaving disposal entirely to local waste authorities or the consumer. In practice this usually means the manufacturer must fund, organise or directly operate the collection, recycling or safe disposal of its own products at end of life.
EPR changes the economics of design described elsewhere in this objective: when a manufacturer knows it will personally bear the cost of recovering a product, a difficult-to-disassemble design becomes a direct cost on the company's own balance sheet rather than a cost hidden in someone else's landfill bill. This is why take-back legislation and EPR schemes create a financial incentive to design for disassembly, single-material components and standardised fasteners.
EPR in practice
- EU WEEE Directive: manufacturers fund and organise collection and recycling of electronic products
- Packaging EPR schemes: producers pay fees scaled to the recyclability of their packaging, rewarding simpler, single-material designs
- Battery take-back schemes: retailers and manufacturers are required to accept used batteries for safe recycling
Case Study
Students must be able toIdentify renewable energy sources and discuss why the circular economy relies on the use of renewable energy.
Renewable energy sources are those that are naturally replenished on human timescales and do not deplete a finite stock:
- Solar: photovoltaic (PV) panels convert sunlight to electricity; solar thermal collectors heat water directly
- Wind: onshore and offshore wind turbines convert kinetic energy of moving air to electricity
- Hydroelectric: flowing or falling water drives turbines; includes run-of-river, dam reservoirs, and pumped-storage systems
- Geothermal: heat from the Earth's interior is used for electricity generation and direct heating
- Tidal and wave: kinetic and potential energy of ocean tides and waves; still emerging at commercial scale
- Biomass and bioenergy: organic material (wood, agricultural waste, purpose-grown energy crops) burned or converted to biogas; considered renewable only when sustainably sourced and managed
Why the circular economy depends on renewable energy: The circular economy's goal is to eliminate waste and pollution across the full system: not just the product, but the energy used to make, process, and recycle it. Fossil fuels are finite and produce greenhouse gas emissions that accumulate in the atmosphere as a form of irreversible waste. A circular economy powered by fossil fuels is not truly circular because:
- Fossil fuels are extracted and consumed: they cannot be "recovered and restored" like materials
- CO₂ emissions from combustion are a form of pollution that cannot be simply recycled back to fuel: they require massive carbon capture infrastructure to offset, which does not yet exist at scale
- Energy must flow through the system continuously; if that flow depletes finite stocks and generates persistent atmospheric pollution, the system cannot claim to be closed-loop
Renewable energy provides the continuous energy flow required by circular processes (recycling, remanufacturing, composting, take-back logistics) without depleting finite resources or generating waste that cannot be managed within the system.
Ten questions covering all five learning objectives, from the linear and circular models through to recovery, restoration and renewable energy. Select one answer per question, then click "Check all answers" to see your score and the explanations.
Q1 · 2.2.1 Linear vs Circular Economy
Which phrase describes the traditional linear economic model?
The linear model runs in one direction and ends in landfill or incineration, treating resources as unlimited and disposal as inevitable. It also depends on non-renewable energy and virgin material inputs. A circular system replaces that final step so materials re-enter production instead of leaving the system.
Q2 · 2.2.1 Linear vs Circular Economy
In a circular economy, the concept of end-of-life is replaced by:
The principle applies across production, distribution and consumption, so no stage of the system is designated as finished. PET bottles collected and remanufactured into new bottles or textiles, and paper recycled repeatedly into new paper, are the everyday illustrations. It is worth asking how closed a loop really is, since most plastics are downcycled once or twice at best.
Q3 · 2.2.2 Design-for Strategies
Which of the following is an example of dematerialisation?
Dematerialisation is a steady fall in the material or energy needed to deliver the same service. Miniaturised electronics and streaming replacing physical discs are the other standard cases. The impact does not disappear, since servers and networks have footprints of their own, but the resource input per unit of value delivered drops sharply.
Q4 · 2.2.2 Design-for Strategies
Jevons observed in 1865 that more efficient steam engines led to greater total coal consumption, not less. The lesson for designers is that:
Cheaper, better steam power spread into more factories, trains and ships, so total coal use rose even as each engine used less. The modern equivalent is a more economical car that makes driving cheap enough to do more of. Countering the rebound effect needs systemic and behavioural design alongside efficiency, such as prompts that encourage running an appliance only when full.
Q5 · 2.2.2 Design-for Strategies
A laptop is designed with modular components so a user can replace a failed part rather than the whole machine. This is:
Longevity is pursued through repairability, upgradability, durable materials, aesthetics that do not date, and an emotional attachment that makes users reluctant to discard something still working. Keeping a product in use is the cheapest loop in the circular model, since a device lasting ten years rather than two removes four replacements from the waste stream.
Q6 · 2.2.3 Biodegradable Materials
Why are biodegradable materials preferred within a circular economy model?
Completing the biological cycle keeps material out of landfill, avoids the methane produced by anaerobic decomposition of buried organic waste, and returns organic matter to the soil. Conventional plastics do the opposite, fragmenting into microplastics that enter food chains and waterways rather than decomposing.
Q7 · 2.2.3 Biodegradable Materials
What is the main limitation a designer must account for when specifying a biodegradable material?
Specific temperature, humidity and microbial conditions are needed for many biodegradable polymers, and labelling alone achieves nothing if that infrastructure is absent at the point of disposal. The designer's responsibility is to specify an end-of-life pathway that is genuinely accessible to the user, not merely available in principle.
Q8 · 2.2.4 Recovery and Restoration
The resin identification codes, the numbers 1 to 7 inside a triangle, exist mainly to:
Code 1 is PET, 2 HDPE, 3 PVC, 4 LDPE, 5 PP, 6 PS and 7 other. Sorting matters because incompatible polymers contaminate a batch: a PET bottle carrying a PVC label is the standard example. Single-material components and clear marking avoid the cost of spectroscopic analysis at the recycling facility.
Q9 · 2.2.4 Recovery and Restoration
Take-back legislation and extended producer responsibility schemes change a designer's incentives because:
Once the cost of end-of-life handling returns to the producer rather than sitting in someone else's landfill bill, design for disassembly, single-material components and standardised fasteners all become financially rational. The WEEE Directive for electronics and packaging fee schemes scaled to recyclability both work this way.
Q10 · 2.2.5 Renewable Energy
Why can a circular economy not genuinely run on fossil fuels?
Materials in a circular system can be recovered and restored, but burnt fuel cannot, and carbon dioxide accumulates in the atmosphere as effectively irreversible waste. Recycling, remanufacturing, composting and take-back logistics all need a continuous energy flow, so that flow has to come from sources that replenish rather than deplete.
Every Paper 2 question is attached to a product. Nothing here can be answered from memory alone: read the case study first, then answer the parts in order. The tariff tells you how many creditable points to make, and the command term tells you what kind of point counts. Write your answer before you open either panel, then mark yourself against the markscheme rather than against the example.
Case study
A dairy delivers milk in glass bottles to doorsteps. The customer rinses the empty bottle and leaves it out; the dairy collects it, washes it at 85 °C, inspects it and refills it. A bottle that fails inspection is crushed and returned to a glass furnace.
The same dairy also sells milk in plastic bottles through supermarkets.
Table 1: The two containers compared
| Glass, returned | Plastic, kerbside recycled | |
|---|---|---|
| Mass empty | 400 g | 28 g |
| Mean trips before retirement | 25 | 1 |
| Energy per trip | Washing only, after first manufacture | Full manufacture each time |
| Return rate | 94 % | — |
| Recycled into | New bottles | Fibre, pipe, lower-grade products |
| Delivery | Local round, electric float | National distribution |
(a) State whether the glass bottle system is an example of reuse or recycling, see Table 1. [1]
(b) Outline why the plastic bottle's recycling route in Table 1 is described as downcycling. [2]
(c) Explain why the 94 % return rate is the figure that determines whether the glass system works, see Table 1. [3]
Example answer
(a) Reuse. The bottle returns to the same function without being reprocessed.
(b) The plastic does not become a new milk bottle; it becomes fibre or pipe, which is a lower-value product that cannot itself be recycled into anything similar again. Each cycle therefore moves the material a step down and the loop terminates, so recycled plastic delays disposal rather than closing the loop.
(c) A glass bottle weighs 400 g against 28 g, so it carries roughly fourteen times the material and manufacturing energy of a plastic one, and the whole case for it rests on spreading that cost over 25 trips. If bottles are not returned they cannot make those trips, and the system loses its only advantage. The arithmetic is unforgiving: at a 94 % return rate the dairy has to replace 6 % of its fleet each cycle, and every replacement is a fresh 400 g of glass melted and moulded. Return rate also determines the size of the fleet the dairy must own and wash, so it drives the cost of running the system as well as its environmental case. This is the general point about a circular economy: the loop only closes if the material actually comes back, and the design of the return route matters as much as the design of the product. That is why doorstep delivery works, since collection happens on a round that is being driven anyway, whereas a supermarket-bought glass bottle would depend on the customer carrying it back.
Markscheme
(a) • Reuse ✓
Award [1] for the correct classification up to [1 max].
(b) An objective of the circular economy is to recover and restore products, components and materials.
• The plastic does not become a new milk bottle ✓
• It becomes fibre, pipe or another lower-grade product ✓
• The recovered material is of lower value than the original ✓
• The lower-grade product cannot itself be recycled into anything similar ✓
• Each cycle moves the material a step down and the loop terminates ✓
• Virgin plastic is still required to make the next bottle ✓
• Downcycling delays disposal rather than closing the loop ✓
Award [1] for each relevant brief point explaining downcycling up to [2 max]. Contrast with the glass, which is recycled into new bottles.
(c) A circular economy is a closed-loop system where resources are continuously repurposed.
• The glass bottle weighs 400 g against 28 g, roughly fourteen times the material ✓
• Its manufacturing energy is correspondingly higher ✓
• The whole case for it depends on spreading that cost over 25 trips ✓
• A bottle that is not returned cannot make those trips ✓
• At 94 % the dairy replaces 6 % of its fleet each cycle ✓
• Every replacement is a fresh 400 g of glass melted and moulded ✓
• A falling return rate would make glass worse than plastic per litre delivered ✓
• Return rate also sets the fleet size the dairy must own and wash, so it drives cost ✓
• The loop only closes if the material comes back, so the return route is part of the design ✓
• Doorstep collection works because it happens on a round already being driven ✓
Award [1] for each relevant reason / cause explaining why the return rate is decisive up to [3 max]. Credit responses that reason from the mass difference in Table 1.
Case study
A packaging company grows protective packaging from mycelium, the root structure of fungi. Agricultural waste such as hemp hurd is packed into a mould and inoculated. Over five days the mycelium grows through the waste and binds it into a solid form. The part is then heated to kill the organism.
It replaces expanded polystyrene used to protect electronics in transit.
Table 2: Mycelium packaging compared with expanded polystyrene
| Mycelium | Expanded polystyrene | |
|---|---|---|
| Feedstock | Agricultural waste | Petrochemical |
| Production energy | Low, ambient growth | High, steam expansion |
| Density | 60 kg/m³ | 16 kg/m³ |
| Compressive strength | Adequate for most loads | Higher |
| Moisture resistance | Poor | Excellent |
| Disposal | Home compostable in 45 days | Persists; rarely recycled |
| Lead time | 5 days growth per batch | Minutes per part |
(a) State the circular economy objective served by a material that is home compostable, see Table 2. [1]
(b) Identify two limitations of mycelium packaging for a manufacturer shipping worldwide, see Table 2. [2]
(c) Evaluate mycelium packaging as a replacement for expanded polystyrene, see Table 2. [3]
Example answer
(a) Incorporating biodegradable materials, so the material returns to the biological cycle.
(b) Poor moisture resistance, which matters on a long sea route through humid conditions; and a five-day growth time per batch, which makes it hard to respond to a change in shipping volume.
(c) The environmental case is strong and it is strong in the right place. The feedstock is agricultural waste rather than oil, production happens at ambient temperature, and disposal needs no collection system at all, because the customer composts it at home in 45 days. That last point matters most, since polystyrene's real failure is that it is technically recyclable and almost never recycled, so a material that decomposes wherever it ends up removes the dependence on infrastructure that does not exist. Against that, it is nearly four times as dense, so more mass is shipped for the same protection, and its moisture resistance is poor, which is a genuine functional failure for goods crossing an ocean rather than a minor drawback. The five-day lead time also forces a manufacturer to hold stock and forecast demand rather than mould parts as needed. On balance it is a good replacement for regional shipping of goods that are not moisture sensitive, and not yet a general substitute, because for a humid sea route the packaging has to survive the journey before its disposal advantage is worth anything.
Markscheme
(a) • To incorporate biodegradable materials ✓
• Returning material to the biological cycle ✓
• Eliminating waste ✓
Award [1] for the correct circular economy objective up to [1 max].
(b) • Poor moisture resistance on a long or humid route ✓
• Five day growth time per batch limits responsiveness ✓
• Density of 60 kg/m³ against 16 means more mass shipped ✓
• Lower compressive strength for heavy or dense goods ✓
• Growth facilities must be near the packing site or the parts shipped ✓
• Biosecurity or import restrictions on fungal material in some countries ✓
Award [1] for each relevant limitation identified up to [2 max]. The limitation must be supported by Table 2 or by the shipping context.
(c) The aim of the circular economy is to eliminate waste and pollution throughout all stages of a product's life cycle.
Strengths:
• Feedstock is agricultural waste rather than a petrochemical ✓
• Production occurs at ambient temperature, so energy use is low ✓
• Home compostable in 45 days, so disposal needs no collection system ✓
• Polystyrene is technically recyclable and almost never recycled, so infrastructure independence is decisive ✓
• Uses a waste stream as an input, which is itself a circular outcome ✓
• No microplastic residue ✓
Limitations:
• Nearly four times the density, so more mass is shipped for the same protection ✓
• Poor moisture resistance is a functional failure for an ocean crossing, not a minor drawback ✓
• Lower compressive strength limits the goods it can protect ✓
• Five day lead time forces stock holding and demand forecasting ✓
• Batch growth cannot respond to a sudden change in volume ✓
Judgment:
• A good replacement for regional shipping of goods that are not moisture sensitive ✓
• Not yet a general substitute, since the packaging must survive the journey first ✓
Award [1] for each distinct strength / limitation, leading to an appraisal of mycelium packaging as a replacement, up to [3 max]. Award a maximum of [2] where only strengths or only limitations are given.
Case study · part 1
A washing machine manufacturer is redesigning its mid-range model. The current machine has a mean life of seven years. The most common cause of retirement is a failed drum bearing, which is pressed into a sealed plastic outer drum that is not sold as a separate part.
Replacing the bearing requires the complete outer drum assembly, which costs more than half the price of a new machine.
(a) Identify two consequences of sealing the bearing inside a non-replaceable drum. [2]
Case study · part 2
The new design splits the outer drum into two bolted halves, so the bearing can be pressed out and replaced.
Table 3: Current and proposed machine compared
| Current | Proposed | |
|---|---|---|
| Mean life | 7 years | 14 years |
| Outer drum | Sealed, welded | Two bolted halves |
| Bearing replacement | Whole drum, £190 | Bearing only, £22 |
| Manufacturing cost | £148 | £163 |
| Retail price | £349 | £379 |
| Machines sold per customer over 14 years | 2 | 1 |
(b) Outline how the bolted drum supports design for disassembly, see Table 3. [2]
Case study · part 3
The manufacturer also proposes publishing repair manuals, selling spare parts to anyone, and using standard fasteners throughout so that a single screwdriver opens the machine.
(c) Describe how these three measures extend the machine's life beyond what the bolted drum alone achieves, see Table 3. [2]
Case study · part 4
The finance director objects that the proposal costs £15 more to make and halves the number of machines each customer buys.
(d) Explain how the manufacturer could remain profitable while designing for a circular economy, see Table 3. [4]
Example answer
(a) A single low-cost component failing retires the whole appliance, and the repair is priced so close to replacement that no rational customer chooses it.
(b) Bolts are a reversible joint and a weld is not, so the drum can be opened without destroying it and closed again afterwards. That turns the bearing into a serviceable part costing £22 rather than a £190 assembly, and it means the drum, motor and other components stay in use instead of leaving with the failed bearing.
(c) The bolted drum makes repair physically possible; these three measures make it actually happen. A manual tells someone which part has failed and how to reach it, selling parts to anyone means an independent repairer or the owner can obtain one rather than depending on the manufacturer's own service network, and standard fasteners mean the job needs no proprietary tool. Without all three, a repairable machine is repairable only in principle.
(d) The objection assumes the company sells machines, and the way to stay profitable is to change what it sells.
The direct answer is that the margin rises on each sale. Cost goes up £15 and price goes up £30, so the proposed machine earns £15 more per unit than the current one. Selling half as many at a higher margin narrows the gap considerably before anything else changes.
The lost volume can be replaced with revenue the current design forgoes. A machine that is worth repairing generates fourteen years of spare part sales at £22 a bearing plus pumps, belts and seals, and those parts carry good margins. The manufacturer currently sells none of that, because at £190 the customer buys a new machine from whoever is cheapest, so the repair market is revenue the sealed design gives away.
The stronger move is to stop selling the machine at all and sell laundry instead, leasing the appliance for a monthly fee and retaining ownership. Under that model a long life becomes an asset rather than a loss, because every extra year is another year of income from hardware already paid for, and the incentives of the business and the circular economy point the same way. It also guarantees the machine returns to the manufacturer at end of life, which is where the material recovery in a circular economy actually happens.
Finally, the fourteen-year machine changes what the brand is. A washing machine is bought on a reputation for lasting, so durability that is demonstrable is a marketing asset, and it protects against regulation, since repairability requirements and spare part obligations are tightening and a company that has already designed for them is not caught retrofitting.
Markscheme
(a) Designers can eliminate waste through longevity, upgradability, disassembly and dematerialization.
• A single low-cost component failing retires the whole appliance ✓
• Repair costs more than half the price of a new machine, so nobody repairs it ✓
• Working components leave with the failed one ✓
• Materials go to waste while still serviceable ✓
• The customer has no viable choice other than replacement ✓
• Independent repairers are excluded because the part is not sold ✓
Award [1] for each relevant consequence identified up to [2 max].
(b) Design for disassembly considers how components of a product can be separated.
• Bolts are a reversible joint; a weld is not ✓
• The drum can be opened without destroying it and closed again afterwards ✓
• The bearing becomes a serviceable part at £22 rather than a £190 assembly ✓
• Repair becomes economically rational for the owner ✓
• Drum, motor and other components stay in use instead of being retired ✓
• Separable parts can also be sorted by material at end of life ✓
• Mean life doubles from 7 to 14 years ✓
Award [1] for each relevant brief point on how the bolted drum supports disassembly up to [2 max].
(c) An objective of the circular economy is to recover and restore products, components and materials.
• The bolted drum makes repair possible; these measures make it happen ✓
• A manual tells the repairer which part failed and how to reach it ✓
• Diagnosis is often the barrier rather than the physical work ✓
• Selling parts to anyone allows an independent repairer or the owner to obtain one ✓
• It removes dependence on the manufacturer's own service network and its pricing ✓
• Standard fasteners mean no proprietary tool is required ✓
• Without all three the machine is repairable only in principle ✓
Award [1] for each detail, leading to an account of how the three measures extend life beyond the bolted drum, up to [2 max]. Award a maximum of [1] where the response addresses only one measure.
(d) A circular economy is a closed-loop system where resources are continuously repurposed, and business models must be redesigned alongside products.
Margin per unit:
• Cost rises £15 and price rises £30, so margin rises £15 per machine ✓
• Selling half as many at a higher margin narrows the gap before anything else changes ✓
• A demonstrably longer life supports the higher price ✓
Spare parts revenue:
• A repairable machine generates fourteen years of part sales ✓
• Bearings, pumps, belts and seals carry good margins ✓
• The current design gives this revenue away, since at £190 the customer buys a new machine ✓
• That replacement may be from a competitor, so the sealed design risks losing the customer entirely ✓
Product as a service:
• Lease the machine for a monthly fee and retain ownership ✓
• A long life becomes an asset, since every extra year is income from hardware already paid for ✓
• Business incentives and circular economy incentives then point the same way ✓
• Ownership guarantees the machine returns at end of life for material recovery ✓
• Recovered components can be reconditioned into the next machine ✓
Strategic value:
• Durability is a marketing asset in a category bought on reputation for lasting ✓
• Repairability and spare part regulation is tightening, so the design anticipates it ✓
• A company already compliant is not caught retrofitting later ✓
Award [1] for each relevant detail / reason / cause relating to how the manufacturer could remain profitable up to [4 max]. Award a maximum of [3] where the response does not go beyond the unit margin argument. Credit responses that propose a product-as-a-service model.
What is a circular economy? Ellen MacArthur Foundation
ellenmacarthurfoundation.org/topics/circular-econom…
The leading resource on circular economy principles, with diagrams, case studies and an animated explainer. Start here if the loop in 2.2.1 has not clicked yet.
Circular Economy Action Plan, European Commission
environment.ec.europa.eu/strategy/circular-economy-…
The 2020 plan under the European Green Deal, including the 2050 climate neutrality target. Policy driving product design decisions across an entire continent.
Conceptualising the circular economy, Kirchherr et al. (2017)
doi.org/10.1016/j.resconrec.2017.09.005
The paper the definition in 2.2.1 comes from. The authors analysed 114 separate definitions of circular economy, which tells you something about how loosely the term is used.
Resin identification code, Wikipedia
en.wikipedia.org/wiki/Resin_identification_code
Codes 1 to 7, what plastic each one is, and the important detail that the chasing arrows symbol never meant the item was recyclable.
Jevons paradox, Wikipedia
en.wikipedia.org/wiki/Jevons_paradox
Why making something more efficient can increase total consumption of it. The rebound effect that undercuts efficiency arguments, first noticed with coal in 1865.
Dematerialization, Wikipedia
en.wikipedia.org/wiki/Dematerialization_(economics)
Delivering the same value with less physical material, with the streaming and digital media examples. Includes the counterargument that the servers are still material.
Right to repair
europarl.europa.eu/topics/en/article/20230601STO938…
fairphone.com/en
The EU rules explained by the European Parliament, next to a manufacturer building repairability into a phone. Policy and product for the same idea in 2.2.4.
Five-year plans of China, Wikipedia
en.wikipedia.org/wiki/Five-year_plans_of_China
How China sets and revises national targets in five year cycles, which is the planning structure referenced in 2.2.1.
PET bottle recycling, Wikipedia
en.wikipedia.org/wiki/PET_bottle_recycling
Collection, sorting, shredding and remanufacture, plus realistic figures on how much PET actually returns as new bottles.
Linking Questions
- How can high-fidelity prototyping techniques ensure a product can enter the circular economy? (A2.2)
- Which manufacturing techniques should be avoided when designing products for a circular economy? (A4.1)
- To what extent does material selection affect a product's suitability as part of a circular economy? (B3.1)
- How can modular electronic systems aid a design for a circular economy strategy? (B3.4)
- To what extent does the selection of a particular production system prevent a product from being suitable for integration into a circular economy? (B4.1)
- Why are some products that are developed using a design for sustainability strategy not suitable to be part of a circular economy? (C2.1)
- How can the suitability of a product for a circular economy be determined through product analysis and evaluation? (C3.1)
- To what extent are products designed for a circular economy likely to result in a positive outcome of a life-cycle analysis? (C3.2)
- To what extent do design for manufacture strategies promote a design for a circular economy strategy? (C4.1)
Case Study: Fairphone
Take the back cover off a Fairphone and the first thing you see is a battery held in by two ordinary screws, not epoxy glue heated with a heat gun. Every major component- the screen, the camera, the speaker, the USB-C port- is its own separate module. Further, each one carries a small icon printed directly on it showing which screwdriver removes it. This is very, very different from an Apple, Huawei, or Samsung phone- where repairability is often limited or impossible.
Fairphone sells every one of those modules directly, and publishes exactly how long it commits to supporting each phone with software updates, working directly against the technological obsolescence covered in C1.1. Independent repairability audits from iFixit routinely score Fairphone models 9 or 10 out of 10, compared to scores typically ranging in the 3-6 area for other flagship phones. None of this has made Fairphone a market leader. It remains a small niche brand next to Apple and Samsung, which raises a question: if repairability is genuinely popular with consumers, why hasn't it won?