Plastic V Cardboard: Which is Greener?

When considered over the lifetime of the packaging, paper and cardboard embody far more greenhouse gases than their plastic equivalents.

From Carbon Commentary, part of the Guardian Environment Network


Riverford Organics, one of the largest vegetable box schemes in the UK, has suggested it may move away from cardboard packaging and towards plastic. In this week’s note to customers, Guy Watson at Riverford says that plastic boxes could reduce the carbon footprint of the company’s packaging by 70%. He strongly hints that the company wants to move to plastic immediately but is frightened of the reaction of customers.


This issue is an important one. Householders continue to see plastic as wicked and paper-based goods as benign. But when considered over the entire life of the packaging, paper and cardboard embody far more greenhouse gases than their plastic equivalents.


Paper products take substantial amounts of energy to make. Crushing a tree down into small fibres, mixing the wood pulp into a slurry and then passing the wet mass through huge rollers cannot be done without use of enormous quantities of power. Making paper and cardboard is almost certainly the third largest industrial use of energy on the planet. By contrast, plastic is light, durable and its manufacture is generally not particularly energy intensive – at least by comparison to paper.


A second concern is that many paper and cardboard products, probably including Riverford boxes, end up in local authority landfill, where they rot down anaerobically, creating the greenhouse gas methane in the process. Plastic, as is well known, doesn’t rot and sequesters its carbon for ever.


Guy Watson’s company delivers its products to homes in cardboard boxes that can be returned to the delivery driver the following week. Watson says that the boxes are designed to last for ten delivery cycles before being recycled. They typically only actually survive four outings before they are lost or made unusable. Because these boxes are ‘free’, the householder doesn’t look after them properly. As a result, about 10% of the total carbon footprint of the business is derived from making and recycling the boxes. This is about the same figure as the carbon cost of shipping the Riverford vegetables to the local distribution hubs. If I have done the calculations correctly, the carbon cost of its boxes would be greater than plastic replacements even if they did actually last 10 cycles and were never used, as the company says, ‘to let the dog give birth in’.


Riverford has done some of the best and most incisive work on carbon footprinting of any business in the UK. The company’s view seems to be that that plastic – far more reusable than paper and cardboard – is a far better solution that its current packaging both for the outer boxes and for carrying the individual products. Its sense of frustration is palpable as it says 85% of our packaging footprint is mad