With low IQ to Smart Packaging

The so-called impact quotient is the proportion of ecological expenditure for the production of the packaging in relation to the filling material. The smaller the IQ, the more ecologically sensible the packaging.

"The carbon footprint is an important measure that quantifies the impact of a company or product on climate change. It gives us the opportunity to identify the specific areas where the highest emissions are generated. This enables us to develop strategies to reduce these efficiently and promote more sustainable business practices, "explains Wilhelm Dyckerhoff, member of the Papiersackindustrie e.V. (GemPSI). "Compared to other packaging, a paper bag already has a very low, even partially negative, carbon footprint." For a paper bag for 25 kg of food, for example, it is only 6 g CO₂e/kg filling weight. In comparison, a 1 liter disposable PET bottle for water has an average carbon footprint of 96.5 g CO₂e/kg filling weight, and a packaging for disc cheese 313 g CO₂e/kg filling weight.

"Whether a packaging makes ecological sense can be assessed if the interplay between packaging and bottled product is considered," says Dyckerhoff. "Packaging for high-quality products is not only the carbon footprint of packaging, but also the savings achieved by product protection."

Packaging provides comprehensive protection

Packaging assumes various protective functions. Primarily, it protects the packaged product mechanically during transport and storage, but also from damage caused by moisture or oxygen. Therefore, packaging should be tailored to the entire supply chain of the bottled product. "In order to develop an ecologically sensible paper bag, it even makes sense in some cases to use more material to save CO₂ on better product protection," says Dyckerhoff. "We handle it according to the motto: As much as necessary, but as little as possible. As an independent processor, we advise our customers on which material and how much of it is appropriate. "

Carbon footprint of a paper bag

Scope 1, 2 and 3 emissions are incorporated into the calculation of the carbon footprint of a paper bag. Scope 1 affects all emissions generated by the company, for example by operating plants and vehicles. Scope 2 describes indirectly generated emissions by using purchased energy. Scope 1 and 2 are the easiest way to influence paper bag manufacturers. "There are various initiatives within the GemPSI member companies, for example by modernizing the systems, using electric vehicles and energy-saving energy management," explains Dyckerhoff. "However, Scope 1 and 2 account for only two to four percent of the carbon footprint of a paper bag. Scope 3 has the largest share with around 90 percent. " This includes all indirect emissions in the upstream and downstream supply chains, from purchased raw materials and their production and transport to the end of a product's life cycle. The corresponding data for the paper bag can be used by processors with the RISE carbon footprint calculator for their customers.

Influencing factor of raw material on Scope 3 emissions

Of the purchased raw materials, paper as the main component of the paper bag has a major influence on its Scope 3 emissions. The sack-power paper used consists of renewable raw materials that are extracted from sustainably managed forests. In Germany alone, despite intensive economic use thanks to sustainable forestry, the forest area has increased by more than 1 million ha in the last 50 years. "Our industry is actively committed to sustainable forestry and reforestation," says Dyckerhoff. Last but not least, the increase in the forest population makes an important contribution to climate protection. Because forests act as a carbon sink.

Negative carbon footprint - positive for the climate

Much of this CO₂-storage is preserved in the further processing of wood to paper. Paper bags are therefore involved in the storage of CO₂ throughout their lifecycle. Among other things, if this storage property were to be included in the calculation of the carbon footprint of an average paper bag, it would already be positive for the climate according to a 2020 study by RISE with minus 35 g CO₂e per paper bag. Other packaging materials can be produced by recycling from the valuable long-fiber raw material of the paper bags. According to a 2021 study by Graz University of Technology, wood-fibre-based packaging can be recycled more than 25 times without significantly reducing its mechanical properties. According to the Fraunhofer Institute UMSICHT, an average of 183 kg of climate gases and 3,150 kg of primary resources (wood) were saved for recycling of one tonne of kraft paper bags in 2021.

Make the right choice

"With a careful and clever selection of the raw materials used and their suppliers as well as clever design variants, emissions can be reduced even further," says Dyckerhoff. "Thanks to the efforts of our raw material suppliers, we will have even more opportunities to reduce our Scope 3 emissions in the future." Whether paper or barrier protection film - by selecting the best materials as well as by constructive refinements there are many possibilities to further lower the carbon footprint of the paper bag.

Product protection along the supply chain

The IQ defined by the Munich University of Applied Sciences provides a good indicator of finding the minimum CO₂-effort for the overall "packaging" system. It describes how much percent of the packaged products must be protected from damage, so that the resulting CO₂-reduction is greater than the expenditure for the production of the packaging used. "The inclusion of the packaged goods in the packaging design makes sense for the development of the ecologically optimal paper bag, but also demanding, because it requires a lot of knowledge. We can best advise our respective customers by understanding the downstream supply chain of their product, "explains Dyckerhoff. "Then we can configure a paper bag for them with as little carbon footprint as possible."

Low impact quotient of paper bags

Paper bags are extremely durable and tear-resistant. With a low dead weight of the packaging, they typically hold 15 to 25 kg of filling weight. Therefore, their IQ is generally low. A typical food bag has, for example, an IQ of 0.16%. This means that if one of 625 paper bags is saved from damage, it has caused less CO₂ than would be caused by product loss. In the case of a chemical bag, only around every two thousand bags would have to be saved from damage. "In general, particularly small IQ values indicate that the protection of the packaged product is particularly important," explains Prof. Dr. Dirk Burth, Munich University of Applied Sciences. "The CO₂-emissions of possible product loss in this case are higher than the emissions generated by the packaging."