Waste, Repair, and Reuse: Worked Examples

By Better Wise

In the last module you sized up the big four: food, home energy, travel, and shopping. This lesson adds a fifth lever that costs nothing to pull: time. Every product you already own carries emissions that were paid for at the factory, so the cheapest and lowest-carbon item is usually the one sitting in your cupboard. Here we trace real items through the waste hierarchy and put numbers on both the carbon and the cash.

By the end of this lesson you can:

• Place any household item on the waste hierarchy and explain why the order matters.
• Estimate the embodied CO2e you avoid when you repair instead of replace.
• Compare repair, second-hand, and new by cost per year of use.
• Recognise the rebound trap that turns a good reuse habit into extra consumption.

The Waste Hierarchy, From Best to Last Resort

The waste hierarchy is a ranked list, not a menu. Options higher up save more emissions and more money.

flowchart TD
  A["🛑 Prevent<br/>Buy less, choose longer-lasting"] --> B["🔧 Repair and reuse<br/>Fix, patch, resell, buy second-hand"]
  B --> C["♻️ Recycle<br/>Material returns to the loop"]
  C --> D["🔥 Recover<br/>Energy from burning waste"]
  D --> E["🗑️ Dispose<br/>Landfill"]

The key insight for durables (appliances, electronics, furniture, clothing) is that roughly 70 to 80% of lifetime emissions happen before you first use the product. That chunk is called embodied carbon, and it is already spent. Repair extends the life of emissions that have been paid for, which is why the second rung of the ladder so often beats the third: recycling recovers materials but loses the energy and labour baked into the finished object.

Note: For food scraps the logic is different. In landfill, food breaks down without oxygen and releases methane, a much stronger greenhouse gas than CO2. Separate food waste collection or home composting tackles that directly, and it does not reduce the emissions of growing the food in the first place.

Worked Example 1: The Washing Machine That Would Not Spin

A six-year-old machine stops draining. A new door seal and drain pump cost €130 fitted. A comparable new machine costs €550 and carries about 350 kg CO2e of embodied emissions (typical range 250 to 500 kg).

• Cost per year of use. Repair: €130 over 5 more years is €26 per year. New: €550 over 10 years is €55 per year.
• Carbon per year of use. The existing 350 kg CO2e spread over 15 years instead of 10 drops from about 35 kg per year to about 23 kg per year.
• Money and carbon avoided in year one. About €420 and about 350 kg CO2e.

That last line is the punchline of this whole lesson: repair is one of the few climate actions that pays you back immediately rather than over decades.

Worked Example 2: A Laptop and the Embodied Carbon Clock

A four-year-old laptop holds a charge for 40 minutes. A replacement battery costs €90 and buys roughly two more years. A new equivalent laptop costs €900 with about 300 kg CO2e embodied.

$$ \text{cost per year} = \frac{\text{purchase or repair price}}{\text{years of service}} $$

• Battery: €90 ÷ 2 years = €45 per year.
• New laptop: €900 ÷ 4 years = €225 per year.
• Emissions avoided: about 300 kg CO2e, roughly what a petrol car emits over 1,200 km.

Manufacturers often price repairs close to a new device, so check the battery and storage first. Those two parts cover the majority of "it is too slow" complaints, and both are usually replaceable.

Worked Example 3: Clothing, Second-Hand, and the Rebound Trap

A new pair of jeans carries roughly 25 kg CO2e (range 15 to 35), mostly from cotton growing, dyeing, and shipping. A patch and a reinforced seam cost €15 or nothing at all. Two more years of wear avoids one purchase: 25 kg CO2e and €55 or more.

Buying second-hand works on the same principle. A €20 used pair skips the production emissions entirely, leaving only a small footprint for transport and washing. The trap arrives on the next rung down: if second-hand prices tempt you into buying five pairs you did not need, your total consumption and your total spending both go up. Reuse only counts when it replaces a purchase you would otherwise have made.

Practical supports worth knowing: Repair Cafés lend tools and volunteer know-how for free or a small donation, many countries now require spare parts and manuals under right to repair rules, and manufacturer-refurbished units usually carry a warranty at 20 to 40% below new.

Rules of Thumb That Survive Real Life

• Ask "what breaks first?" Batteries, seals, belts, zips, and screens fail long before the rest of the product. Price that part before you price a replacement.
• Divide by years, not by sticker price. A €90 repair that lasts two years competes with a €900 purchase that lasts four, not with the purchase price alone.
• Use the 30-day rule. Put an item you want on a list and revisit it in a month. Most wants expire, and the ones that survive are the purchases worth making once, well.
• Skip the guilt about recycling imperfectly. If an item is genuinely dead, recycling is a fine landing spot. It is just not a substitute for the two rungs above it.

Key facts to lock in before the next lesson:

• The waste hierarchy runs prevent, then repair and reuse, then recycle, then recover, then dispose.
• About _____ of a durable product's lifetime emissions occur before first use.
• Repairing a machine with 350 kg CO2e of embodied carbon avoids that _____ when it replaces a new purchase.
• Recycling recovers materials but not the _____ already invested in the finished product.
• Second-hand shopping only reduces emissions when it _____.
• Comparing options by _____ is the fastest way to see that repair usually wins on money as well as carbon.

What to Take Away

Keeping things in use is the highest rung of the waste hierarchy you can reach without spending anything, and it is the rare case where the low-carbon option is also the cheaper one. Before you replace anything this month, price the failing part, divide both options by years of service, and check whether a repair or a refurbished unit closes the gap.

Next up: Sustainable Purchasing and Spotting Greenwashing, where we take the same numbers-first mindset and point it at labels, claims, and packaging.

Front: What is the order of the waste hierarchy? Back: Prevent, then repair and reuse, then recycle, then recover energy, then dispose.

Front: What share of a durable product's lifetime emissions happens before first use? Back: Roughly 70 to 80 percent, mostly in manufacturing and shipping.

Front: What is embodied carbon? Back: The emissions already spent making and delivering a product, before you use it.

Front: Why does repair usually beat recycling? Back: Recycling recovers material but loses the energy and labour invested in the finished product.

Front: Approximate embodied footprint of a mid-size washing machine? Back: About 350 kg CO2e, with a typical range of 250 to 500 kg.

Front: How do you compare a repair against a replacement fairly? Back: Divide each price by the years of service it buys, so you compare cost per year of use.

Front: Approximate footprint of one new pair of jeans? Back: About 25 kg CO2e, mostly from cotton growing, dyeing, and shipping.

Front: Why is repairing often better than a discount on a new item? Back: The repair avoids the whole embodied footprint and is usually cheaper per year of use.

Front: What is the rebound trap in second-hand shopping? Back: Buying used items you did not need, so total consumption and spending both rise.

Front: What is the 30-day rule for purchases? Back: Wait a month before buying a wanted item; most wants expire.

Front: Where do most emissions from landfilled food come from? Back: Methane released when food decomposes without oxygen.

Front: What does a Repair Café provide? Back: Tools, volunteer repair skills, and help fixing household items for free or a small donation.

Front: Which parts usually fail first on appliances and electronics? Back: Batteries, seals, belts, pumps, zips, and screens, all commonly replaceable.