Lego has been searching for a green alternative to the engineering plastic, from which their toy bricks are made, for a number of years. They have spent large sums on research into biobased and mechanically recycled alternatives. Now, a recent announcement indicates that having failed to find a suitable alternative, they are pursuing the mass balance route to reduce and then eradicate fossil fuel derived raw materials from their supply chain.
Lego’s predicament is a result of the exacting quality standards they have set for the toy bricks, to ensure that the colours are vibrant, and the bricks tough enough to survive years of play. It is a problem shared by many brand owners whose products contain, or are packaged in, polymers. Now Lego has come to the same conclusion as others already have, that making the same high quality consumer products or packaging at scale, directly from recycled or renewable materials, is very difficult if not nearly impossible. The required shift in processing technology, or final specification, is too expensive to implement or too hard to sell. So, the petrochemicals industry, in collaboration with sustainability schemes, is offering an alternative: coprocessing with mass balance accounting.
The most readily available recycled polymers, natural sugars or biobased oils are first treated to ensure they can be mixed with petrochemical feedstocks, and then processed as a mixture in existing facilities. The biobased or recycled raw materials become further diluted as they pass through world scale facilities. The company at the end of the supply chain has a specific mass of the sustainable material allocated to them. Certain sustainability schemes, such as ISCC, and their auditors certify that the mass of raw material purchased is in balance or agreement with the recycled or bio content claimed by brand owners. Hence the term ‘mass balance’ The cost of these materials exceed their conventional counterparts. Lego claims that they are paying up to 60% more.
Many companies are however still persevering with mechanical recycling, whilst adapting to overcome the quality problems. For example, polyethylene and polypropylene recyclates have an unpleasant odour. So, automotive companies are limiting their use to parts which are outside of the passenger cabin, until a solution is found. Also, most plastics suffer a deterioration in their qualities as a result of the melting and re-forming that occurs during the process of mechanical recycling. In response, polymer producers are blending recycled content with specially developed virgin monomers to offset the loss of strength.
Lego is committed to scale up its use of mass balance without passing the cost onto customers. It is a very good start. But is mass balance a solution for a net zero future for all chemicals and plastics? The idea is that, as more and more waste plastic is collected or crops produced, responsible feedstocks will replace fossil ones. But the processing necessary to ensure these new raw materials are compatible with existing chemical facilities can be both energy intensive and inefficient. Losses occur, as waste or less valuable side products. Hence the high price. It is likely that the supply of sustainable raw materials will not be sufficient to cope with the world’s demand for high quality chemicals and plastics, so the need for other sources of carbon will remain. Into the future, captured carbon dioxide, together with renewable electricity, could provide that carbon, but the scale of technology development and investment needed to get there is daunting.
We are only at the beginning of the transition to a net zero chemicals industry. Lego has made a bold move and helped to boost the credibility of the mass balance method of sustainable content allocation, without passing the cost onto consumers. Other brand owners should heed the writing on the (brick) wall.
Watch a video on the mass balance approach
Published: 9 September 24
