Sustainable Packaging Series: Bioplastics

corn leaves, corn field, garden, close-up, flora, rocks, trees

To be honest I’ve been avoiding writing about bioplastics in our sustainability series. Even though I work in developing sustainable packaging and products every day, it remains confusing as new information and counter-information comes to light every day. However, as many of our clients are looking to it as a promising alternative to petrochemical based materials, we need to get to the bottom of it. And it does sounds like a solution doesn't it? Coca-Cola say their PlantBottleTM has been a great marketing success, and it does have a catching ring to it.

Coca-Cola go on to say that they have saved the equivalent of 270,000 tonnes of carbon emissions by including 30% recyclable PLA in their bottles. However, it doesn't really explain why that is. Looking into if further, it would appear that it is based mainly on the principle that the plant material used (waste material in their case) in the production of bioplastics soaks up CO2 from the atmosphere in its growth thus locking it into the plant-based plastic. The CO2 emissions should also be considered and compared in the processing and manufacture of the different plastics. This will depend on all sorts of factors too complex to go into here but let us assume the net saving is real.  

Some bioplastics are compostable, but not all, so this potential benefit is yet another source of confusion. I consider compostables in another article in the series where I discuss how industrial composting is the only real option, but this uses CO2 in creating the necessary heat to speed up the process, possibly countering the CO2 saving from switching to compostable bioplastics in the first place.

Sustainability is not just about greenhouse gasses as the large amount of farming required to replace petrochemical sources (some estimates say it could reach 7% of arable land) creates its own set of problems. Most importantly, food production is going to be stressed with an increasing global population and the adverse climate effects of those CO2 emissions. So, diverting land use to plastics production is a no-no. However, use of waste from food production will be both efficient and sustainable as long as that waste wasn't used for productive purposes in the first place like feeding the soil or livestock. Pollution from fertilisers and the use of water in arable production are other factors that need to be taken into account as well in the sustainable equation and would clearly count against bioplastics use.

 Which begs the question, are bioplastics any better than petrochemical based plastic? Oil is a CO2 sink so digging it out of the ground and burning it puts that carbon right back into the atmosphere, which is not good, but turning it into plastic keeps the CO2 locked in unless of course it is burnt as rubbish. So, we just need to keep the plastic in circulation through reuse and recycling. To put in perspective, plastic production from oil is only in the order of 4% of the total. The 96% is therefore used for fuel and burnt, so reducing plastic from this source is surely not significant in the big picture. It is also cheaper and more highly developed technically than bioplastic…The main target for CO2 emissions reduction has got to be in renewable energy development not alternatives to plastic manufacture.

Back full circle to the main issue facing our clients with single-use packing. Our conclusion has got to be that bioplastics maybe a quick win marketing story, and within the capabilities of consumer goods business to change over to relatively easily but will not fundamentally solve the problem. Add to that the increased COGs, in many cases, lack of technical performance, it seems it would be better if we focus our best efforts elsewhere. When it comes down to it, we have to keep the plastic we manufacture in the system for as long as humanly possible to keep that carbon out of the atmosphere, rubbish off our beaches and particles out of our food chain. That means we need to focus on reducing and recycling, no matter how hard these challenges are to solve – the subject of the next article in the sustainability series.