Calculating GHG emissions
from food packaging

Packaging material

CarbonCloud measures 4 general types of packaging material: Plastic (fossil-based and bio-based), paper, aluminum, glass.

Plastic

Fossil-based

Plastic is produced in different kinds of resin, plastic material in a grain-like shape, that is available in many different kinds, and is then formed into the final packaging form. The most common plastic types used in the packaging industry today are:

• LDPE/LLDPE
• HDPE
• PP
• PET
• HIPS
• GPPS
• PVC
• PA

The climate footprint of plastic packaging is comprised of three main factors:

1. The energy consumption during the production of resin

The emissions from the primary production of each plastic resin type are taken from Plastics Europe.

2. The carbon embedded in the resin

The embedded carbon is added to the resin production emissions according to the carbon content of the plastic molecule for every type of resin. Today, the biggest by far part of all plastics produced have fossil origin.

3. The energy consumption during the processing of resin into the final packaging material

The emissions from the energy used for processing the plastic resin into final products depend on the specific processing type as well as the age and size, hence the efficiency of the machine in question. It also depends on the carbon intensity of the type of energy used. The energy consumption is accounted for according to RECIPE (Reduced Energy Consumption in Plastics Engineering), an EU-funded project.

Bio-based

Bio-based plastic contains carbon that originates from the atmosphere, in contrast with plastic that originates from fossil sources. The release of embedded carbon is equal to the uptake from the atmosphere and therefore results in net zero emissions. The final climate impact of bio-based plastic materials naturally includes emissions from the production of the resin, and the processing of the material to its final form, according to RECIPE (Reduced Energy Consumption in Plastics Engineering), an EU-funded project.

Aluminum

The climate footprint of aluminum is comprised of three main factors:

1.  The energy consumption of the primary production of the aluminum ingot

Aluminum ingot is a metal mass suited for further processing. Different processing techniques have different energy requirements that impact the climate footprint accordingly. The process of turning the raw material into an aluminum ingot is a highly energy-intensive process. Therefore, the emissions from aluminum ingot largely depend on the electricity mix of each country.

CarbonCloud’s model for the primary aluminum ingot is based on data from Aluminium International, which is broken down by geographical region and shows the energy intensity of the different processing steps as well as the energy mix used in the different regions.

2. The recycled content of the aluminum

The recycled content of aluminum is the distinction between how much of the aluminum is primary and how much is secondary. Recycling aluminum is much less energy-intensive than primary production. Since it is merely a matter of remelting the metal scraps, there is much less need for the energy-intensive electrolytic process applied to primary production.

Data regarding the energy requirements for aluminum recycling is taken from European Aluminium. Different regions of the world vary widely in the average mix of recycled and virgin aluminum. This data is also collected from Aluminium International.

3. The energy consumption used during the processing of the aluminum ingot to its final form

Paper

Since paper is a biogenic material, the uptake of the carbon embedded in the paper and the emissions from its decomposition even each other out. Hence, the sum of uptake and emissions from embedded carbon is net zero.

CarbonCloud measures four types of paper packaging:

• Kraft paper
  Thin paper commonly used to package e.g. flour, sugar.
• Paperboard
  Rigid thick material for cartons and boxes.
• Corrugated cardboard
  Thinner cardboard commonly used for secondary packaging, e.g. wrapping a six-pack of canned sodas.
• Liquid packaging board (LPB)
  Commonly used for liquid packaging and often coated with plastic film.

The emissions from paper packaging come from the energy consumed to produce one kilogram of paper and vary depending on the type of paper produced.

The largest energy source in paper and pulp production is pulping liquor and waste wood, followed by natural gas.

Glass

The great bulk of commercial glass for food packaging is Type III (soda lime glass) or Type II (soda lime glass treated to package acidic contents) and is almost entirely soda-lime glass. It consists of silica (SiO2), soda (Na2O), and lime (CaO), with small amounts of alumina (Al2O3), other alkalies and alkaline earths, plus some minor ingredients.

CarbonCloud measures the climate footprint of the glass packaging material based on the input of the typical composition of the ingredients above and the “yield” or the amount of glass produced after processing.

As with every other packaging material, the emissions from the energy used in processing for the final packaging form are added on top of the emissions from the extraction and production of the input material. For glass, emissions from production occur primarily from the high-temperature heat deriving from fuel combustion that is needed to melt and mold the materials into glass.

As with all other packaging materials, the emissions embedded in the material itself are allocated to the primary use of the material. So, for recycled glass, only the emissions from the energy used in the recycling process are calculated.

Finally, much like aluminum, glass packaging is usually a mix of virgin and recycled glass, the combinations of which vary across regions of the world. CarbonCloud accounts for these average variations as stated in FEVE and the US EPA.