Lightweighting

Lightweighting, also known as weight reduction, is a design and production strategy aimed at reducing the amount of material used in a product, component, package or structure, without compromising its functionality, safety or durability.

Its application is essential to improve industrial sustainability, because it reduces:

• The consumption of raw materials.
• The material footprint.
• Waste generation.
• Greenhouse gas (GHG) emissions.
• Energy and transport costs.

In the circular economy, lightweighting is a key tool to dematerialise production systems and move towards more efficient, regenerative models.

Origin and evolution of the concept

The concept emerged in the aerospace and automotive sectors in the mid-20th century, where reducing weight meant greater energy efficiency and better performance.

With the rise of sustainability, it has expanded to sectors such as:

• Packaging.
• Consumer goods.
• Electronics.
• Construction.
• Logistics and transport.
• Retail and food.

Today it is a priority business strategy, driven by the European Green Deal, the EU circular economy plans, Spain's Law 7/2022 and the advance of ecodesign rules under the ESPR.

Main objectives of lightweighting

1. Reduce the amount of virgin material in products.
2. Lower the carbon footprint associated with production, distribution and end of life.
3. Optimise design while maintaining strength, safety and ergonomics.
4. Reduce waste, especially plastics and packaging.
5. Improve logistics efficiency and cut transport costs.
6. Facilitate recycling by reducing mixed or complex materials.

Lightweighting applies both to initial design and to the redesign of existing products.

How it is applied

1. Structural ecodesign

• Reducing wall thickness in packaging.
• Geometries optimised through CAD and simulation.
• Use of lightweight honeycomb or reinforced structures.

2. Material substitution

• Conventional plastics replaced by optimised polymers or biopolymers.
• Heavy metals replaced by light aluminium or fibre composites.
• Multilayer board replaced by mono-material board.

3. Packaging minimisation

• Elimination of secondary packaging.
• Reduction of empty space.
• Concentrated formats (refill, single-dose, compaction).

4. Advanced manufacturing

• 3D printing.
• Advanced polymer injection.
• Nanomaterials and microstructures.

5. Logistics redesign

• Optimised palletisation.
• Lightweight foldable or stackable boxes.
• Weight reduction in load units.

Sectors where lightweighting is most relevant

1. Packaging

This is the leading sector for lightweighting. Examples include lighter-gauge PET bottles, lightweighted glass containers, thinner food trays and the replacement of plastic films with thinner alternatives.

2. Automotive

• High-strength steel.
• Light aluminium.
• Carbon-fibre composites.
• 3D-printed components.

3. Air and rail transport

• Weight reduction in interiors.
• Aerodynamic improvements.
• Lightweight composite materials.

4. Electronics

• Miniaturisation of components.
• Reducing the volume and mass of smartphones or laptops.

5. Construction

• Lightweight prefabricated elements.
• Sandwich panels.
• Advanced lightweight concrete.

Environmental benefits

1. Lower carbon footprint

Less material means less energy and fewer emissions. Depending on the material, each kilogram avoided can represent several kilograms of CO2-equivalent saved across the life cycle.

2. Lower material footprint

A direct improvement in the material footprint indicator, which is central to circular economy strategies such as Spain's Circular Economy Strategy 2030.

3. Better recyclability

Fewer material mixes and simpler structures make recycling easier.

4. Less waste generation

A direct impact on the landfill rate, the recovery rate and the recycling rate.

5. Logistics efficiency

It helps reduce transport emissions, which can be quantified using ISO 14083.

Risks and criticisms

Although generally beneficial, lightweighting can produce unwanted effects:

• Loss of durability, if it is not properly assessed.
• Packaging that is too thin and compromises food safety.
• Recycling difficulties, if new complex composites are introduced.
• Greenwashing, if the weight reduction is communicated without transparency.

For this reason, a life cycle assessment (ISO 14040/14044) should always be carried out to ensure a real improvement.

Lightweighting and the circular economy

Lightweighting is one of the pillars of circular ecodesign:

• It reduces resource extraction.
• It facilitates reuse and refill.
• It optimises recycling.
• It cuts costs and emissions.
• It improves the energy efficiency of the life cycle.

It is also relevant to the disclosures under ESRS E5 (Resource use and circular economy) of the CSRD.

Innovations in lightweighting

1. Topology optimisation using AI.
2. Ultralight nanocomposites.
3. Aerogel plastics and technical foams.
4. Reinforced ultralight glass.
5. Biomimetic structures inspired by nature.
6. Lightweight adhesives replacing metal joints.

Practical examples

Lightweighted PET packaging

Beverage producers have reduced bottle weight (for example from around 22 g to 16 g) while maintaining strength and improving recyclability.

Aerospace

Manufacturers have removed substantial weight per aircraft by applying advanced composites, saving fuel and emissions.

Construction

Use of lightweight panels to reduce transport, foundations and embodied energy.

Retail

Lightweight mono-material packaging to improve recyclability and reduce landfilling.

Metrics and indicators

The most widely used KPIs are:

• Weight reduction per unit (%).
• Avoided emissions (kg CO2e).
• Avoided virgin material (kg).
• Reduction in material footprint.
• Logistics savings (litres of fuel per km).

These indicators can be audited and reported under ESRS E5 (CSRD), GRI 301 and 306, and circularity indicators. At Manglai we help companies measure their carbon footprint and prepare their sustainability reporting. Discover how Manglai can help you.