What is the circular economy? And how is it measured with LCA?

The circular economy is a production and consumption model aiming to keep materials in the economy as long as possible and at as high a value as possible. Its opposite is the linear model: take, make, use, dispose.

The R-hierarchy: recycling is not the best option

Recycling is what comes to mind first, yet it sits fairly low in the hierarchy, which is ordered by how much of the material’s value is preserved.

• Refuse / rethink — is the product needed at all, can the function be met another way
• Reduce — delivering the same function with less material
• Reuse — using the product again as it is; the highest value retention
• Repair and refurbish — extending life, dividing production impact across more uses
• Remanufacture — collecting components and restoring them to new-product standard
• Recycle — melting and reforming the material; part of the value is lost
• Energy recovery — burning it for energy; the material value is lost entirely

Circularity is not automatically good

This is the point that meets the most resistance and matters the most. Recycling also consumes energy: collection, transport, sorting, cleaning, reprocessing. If that chain’s total impact exceeds primary material production, recycling loses environmentally.

In aluminium, recycling uses about a twentieth of the energy of primary production — an enormous gain. For some low-density, contaminated plastics collected over long distances the balance is far finer. The answer depends on the material, the distance and collection efficiency — on measurement, not ideology.

How LCA measures circularity

There are two basic approaches, and they give different answers for the same product. Under cut-off, recycled input carries only collection and reprocessing burden; the primary production burden stays with the first user. Under avoided burden, the recycling credit goes to whoever sends the material for recycling.

EN 15804+A2 uses cut-off and reports end-of-life recovery potential separately in Module D. That separation is critical: Module D’s negative value cannot be netted off the A1-A3 total, because that benefit lies outside the system boundary and is an assumption about the future.

Measurable circularity indicators

• Recycled content share — the secondary material fraction of the input
• Recyclability rate — the share recoverable at end-of-life
• Reference service life — how many years the product performs
• Number of reuses — decisive in refillable systems
• Resource use indicators — primary and secondary material, renewable and fossil energy