Choose effectiveness over efficiency. Always.

I'm not sure if it's the sunshine or the fact that our cherry trees are bursting into blossom, but I found myself thinking back to my first encounter with the circular economy. I joined the Ellen MacArthur Foundation in summer 2019 to lead the Higher Education function. Very quickly, I was immersed in learning about the circular economy, where it stemmed from, the thought leaders that had contributed and along the way, became very familiar with the cherry tree analogy, popularised by Michael Braungart and William McDonough in their book Cradle to Cradle: Remaking the Way We Make Things.

The analogy goes like this: a cherry tree blossoms each year and each year produces infinitely more blossoms than will go on to become cherries that will then seed new trees. This is not efficient. An efficient cherry tree would only produce as many blossoms as will become cherries to reseed and keep the population going. It certainly wouldn't waste blossoms by letting them fall to the ground. However, by overproducing blossoms, a cherry tree is being very effective. The excess blossoms fall to the ground and become nutrients in the soil, upon which the cherry tree is reliant. More blossoms feed more insects, keeping natural ecosystems in balance and keeping other species alive.

If the cherry trees were efficient rather than effective, over time the number of cherry trees would go down as fewer and fewer blossoms would be produced, the soil would have fewer nutrients and insects would have less access to food. The system upon which a cherry tree survives would break. By being effective, the cherry tree has ensured its long-term survival.

I regularly used this analogy with students or when talking to businesses to demonstrate how our obsession with efficiency in the linear economy has led to economic and environmental instability, and how nature gives us all the lessons we need to build an economy which thrives in the long-term. Choose effectiveness over efficiency. Always.

In recent years, that analogy and story has been consigned to the shelves as a new narrative has taken hold. The increased urgency with which we need to curb carbon emissions has meant that efficiency is thriving as much as ever - and still perpetuating a system based on linear throughput, even if much of it looks 'better' on the outside because it meets carbon reduction targets.

Efficiency can definitely make things less bad, but does it always make them better, or fit for a circular economy? Now, I am not a specialist in plastics, LCAs or the number crunching, but this tension between efficiency versus effectiveness plays out in my fridge in a way that really annoys me, and I think highlights the challenge well.

Let me share that with you.

The humble pot of hummus. Hummus has become the unlikely victim in demonstrating how carbon reduction ambitions are just efficiency dressed up rather than an effective overall approach to a new economic model where both people and the planet thrive. Well, not actually hummus (chickpeas are excellent, as are all legumes - for human and planetary health) but in particular the pot the hummus comes in. The one that is a rigid plastic pot with a thin, flexible plastic film lid. This of course applies to yoghurts, all dips, soft fruit packaging, and so on.

A few years ago, you'd go to the shop to buy hummus and it would come in a rigid plastic container with a rigid plastic lid. In our house we never finish a pot of hummus in one go, so the rigid lid meant that we could store it in the fridge for a few days so it didn't go to waste. We also used to wash the containers and the kids would put their school snacks in them, giving them more than one use. And, when they inevitably broke, both the container and lid went into our household recycling. Then off to the recycling plant and made into new hummus pots - or something else. You get where I am going (that 'circulate' principle of the circular economy).

Let's contrast this with the hummus pot of today. Rigid plastic tub with flexible film lid. As we invariably still don't finish the tub, we now have to deal with a tub without a lid or seal. Realistically we have a few options: it sits open in the fridge, goes a bit crusty and eventually hits the food waste bin; it gets scraped into a plastic container with a lid and stored for a few more days to be finished; or (this does not happen in my house, but it's what my parents would do) clingfilm gets used. *Shudder.* In all these scenarios, the film goes into the general waste and hopefully the tub gets recycled.

So, why does this bother me so much?

In 2024, a spokesperson for one national retailer said: 'We have recently removed the lids on our hummus pots as part of our ongoing efforts to tackle plastic waste. This latest change will remove more than 31m pieces of plastic - equivalent to 157 tonnes of plastic a year.' This of course means less fossil fuels are used, which is a good thing, but…

Does it really remove the pieces? It simply changes one form of plastic to another, with thin flexible film being way less recyclable, so one could argue that in fact this move has added plastic to the environment. If lids were still made with recyclable, rigid plastic they could be kept in circulation, used longer, have more than one life, and so on.

And don't even get me started on the food waste element. If you assume that a third of the pot is unused and sits withering in the fridge (due to the lack of a suitable lid), the equivalent in food waste tonnage (157) has a much higher emissions footprint than the savings made by switching to film. Even if you assume a large quantity ends up in a food waste bin and heads into composting or anaerobic digestion, the figures for emissions as a result of food waste are vastly bigger than the savings made by switching the lids and reducing the amount of fossil fuels used to make the plastic. In fact, a conversation with my favourite AI partner says that wasting the food is worse than wasting the lid. But hey, the retailer scores on plastic reduction and emission reductions while the poor customer is left with the guilt and responsibility of dealing with the consequences.

Now, I am not an LCA specialist and there is a lot more to be calculated, but if every decision is driven by carbon reductions, we will miss out on creating a truly circular economy. In this case, the supermarket gets closer to meeting its net zero ambitions. The customer loses. Yes, we use less fossil fuels and yes, that lowers emissions, but we have created another set of issues. Efficient yes, effective - well, no. Not in my house anyway!

Until we design for effectiveness - not just efficiency - we're only making the linear economy slightly less bad, rather than creating a truly circular one.

PS. I have recently been shopping at a different national retailer as it is near where my children do ballet, and was delighted to find that some hummus pots still have a rigid lid.

PPS. Perhaps if my youngest child liked hummus, we wouldn't have this pesky food waste problem.