New research has revealed that within the same grade (brand), the carbon footprint of a cartonboard reduces at least in proportion to its basis weight. For example, a 15% reduction in board weight equates to a 18% reduction in carbon footprint.
To make the potential for carbon footprint reduction easier to visualize, Metsä Board has calculated that if you make 100,000 biscuit cartons using a board that is just 25 g/m2 lighter, the annual CO2 saving equals driving 1,000 km by car.
The findings are of considerable interest to brand owners and converters concerned about the sustainability of packaging. If they can specify a lighter weight board, provided all criteria regarding stiffness and performance are met, the carbon footprint will diminish accordingly.
Lightweighting combines ecology and economy
The research, commissioned from an external research institute by Metsä Board Consumer Packaging, aimed to produce Life Cycle Assessments for three different weights of the same board grade. Carbon footprints were calculated for 10,000 biscuit cartons produced with cartonboards of different weights (250, 270 and 295 g/m2), to discover if the footprint would reduce proportionately when a lighter weight board was used. Calculations assessed energy used in all stages of forestry, transport and manufacturing , from harvesting the wood to making the cartons including, for example, transporting the board to the customer.
Riikka Joukio, Vice President Marketing of Metsä Board Consumer Packaging, says: “By making packaging more effective and less wasteful, sustainability goes hand in hand with cost savings, which can be achieved both by the choice of lightweighted materials and by a design that has the right impact.”
“Other industry research has shown packaging has a relatively small global warming potential, between 5−15%, compared to other activities in the production of a food product, most notably fertiliser and cultivation, which account for 22% and 50% respectively.* At the same time, packaging’s importance in reducing food waste, which might otherwise rot down in landfill producing methane – a harmful greenhouse gas – is shown in another study.** This has found that up to 50% of food is wasted in developing countries, where food packaging is less common, compared to western countries where waste averages 2% and is mostly attributable to over-purchasing.”
* MTT Agrifood Research Food Finland and Finnish Packaging Association
** GEM – IFEC Promotion/United Nations