DT
IB Design Technology
SL · Lesson 41 · Design for a Circular Economy
01 / 15
Lesson 41 · Unit 5

Design for a Circular Economy

Move from “take–make–waste” toward a closed loop that keeps products, components and materials useful.

80 minutesC2.2.1–C2.2.5
Guiding question: How can designers minimize waste and pollution by keeping resources in circulation?01
Today’s destination

By the end of class, you should be able to…

01

Compare systems

Distinguish linear from closed-loop circular flows.

02

Design out waste

Use longevity, upgradability, disassembly and dematerialization.

03

Plan recovery

Use biodegradable pathways, take-back, reuse, repair, recondition and recycling.

04

Connect energy

Explain why circular systems still depend on renewable energy.

Success check: Explain the concept accurately, then use it to make a justified design decision.
C2.2 · closed-loop systems02
C2.2.1

Take → make → use → waste

Extract

Resources enter the system.

Manufacture

Energy/material are transformed into products.

Use

Value is delivered for a period of time.

Dispose

Resources leave as waste; value is lost.

Linear economy · one-way resource flow03
C2.2.1

A closed loop tries to preserve value.

Products, components and materials are continuously repurposed rather than automatically becoming waste after one use cycle.

Compare the system logic, not only whether a product contains recycled material.
Circular economy · resources continuously repurposed04
C2.2.2

Waste is a design problem upstream.

Longevity

Keep the product useful for longer through durability, maintenance and lasting value.

Upgradability

Allow performance/features to improve without replacing the whole product.

Disassembly

Make components separable for repair, recovery and material sorting.

Dematerialization

Deliver the required function with less material / fewer physical resources where appropriate.

C2.2.2 · four required strategies05

Fasteners communicate a future.

Hard to recover

Permanent mixed-material bonding can make repair and separation difficult.

Designed for recovery

Accessible reversible joints, clear component separation and material identification can support repair/recycling.

C2.2.2 · design decisions affect recovery06
C2.2.3

Biological cycles are one circular pathway.

Biodegradable materials are preferred when they can safely break down in an appropriate biological/end-of-life system instead of persisting as waste.

Biodegradable does not mean “throw it anywhere.” Designers still need a realistic end-of-life pathway and correct conditions.
C2.2.3 · biodegradable materials in circular models07
C2.2.4
SystemTake-back legislationRequires/encourages producers or systems to take responsibility for products after use.
Keep productReuseUse the product/component again with minimal intervention.
Keep functionRepairFix faults so the product continues its intended use.
RestoreReconditionRestore a used product/component to an acceptable working condition.
Recover materialRecyclingProcess materials into feedstock for future products.
C2.2.4 · recovery/restoration strategies08
Use longerMaintain / longevity
ReuseSame product/component
RepairRestore function
ReconditionRestore working condition
RecycleRecover material value
This value-preservation hierarchy is a useful design lens; the syllabus specifically requires discussion of reuse, repair, recondition and recycling.
Recovery decisions start during design09
C2.2.5

A material loop still consumes energy.

Solar

Energy from sunlight.

Wind

Energy captured from moving air.

Hydroelectric

Energy from moving/falling water.

Geothermal / other renewables

Locally appropriate renewable sources can power circular processes.

Why it matters: recovery, repair, reprocessing and transport can still create emissions if powered by non-renewable energy.
C2.2.5 · identify sources + explain reliance10
Knowledge check

A phone is designed with a replaceable battery, standardized screws and a manufacturer take-back program. Which interpretation is strongest?

C2.2 · evaluate the system, not one feature11

Take one product from your IA research.

1
How could it last longer?
2
What could be upgraded?
3
What should be easy to disassemble?
1
What could be reused/repaired/reconditioned?
2
Which materials need a biological or technical recovery path?
3
How could a take-back system work?
Transfer C2.2 to your own design context12
Design for sustainability

Balances environmental, social and economic decisions; uses principles such as cyclic/solar/safe/efficient/social and TBL.

≠
Circular economy

Specifically focuses on closed loops: eliminate waste/pollution, keep resources in use, recover/restore value and use renewable energy.

A product can improve sustainability without fully fitting a circular system—and vice versa requires careful analysis.
C2.1 and C2.2 are linked, not identical13
Name the four C2.2.2 design strategies for eliminating waste/pollution.
Longevity, upgradability, disassembly and dematerialization.
Name the recovery/restoration approaches required in C2.2.4.
Take-back legislation, reuse, repair, recondition and recycling.
Why does a circular economy rely on renewable energy?
Keeping resources in circulation still requires energy for production, transport, repair and reprocessing; renewable energy reduces the system’s dependence on depleting/high-impact energy sources.
C2.2.1–5 · complete retrieval14
Exit ticket

Before you leave…

1. Explain one difference between a linear and circular approach.
2. Choose one circular design strategy your IA redesign could use.
3. Explain why renewable energy matters even if materials are successfully recovered.
Next lesson

IA Day 12 — Criterion C Development

Keep the evidence chain moving: user → research → decision → test.

Curriculum alignment
C2.2.1 compare linear and circular economy. C2.2.2 eliminate waste/pollution through longevity, upgradability, disassembly, dematerialization. C2.2.3 biodegradable materials. C2.2.4 recover/restore via take-back legislation, reuse, repair, recondition, recycling. C2.2.5 identify renewable energy sources and discuss why circular economy relies on renewable energy.
Lesson complete15 slides
Designed by David Xu · © 2026 David Xu. All rights reserved.Educators and students are welcome to use these materials for non-commercial teaching and learning with attribution. Please share the original link when possible. Reposting, redistributing modified copies, removing attribution, or commercial use requires prior permission.
IB Design Technology SL · Lesson 4115