The Climate’s resident barista explains the environmental impact of coffee and where the industry can do better.
I recently started working as a barista part-time. While I enjoy the job, I was immediately struck by the vast amount of coffee my café uses in a day. I have always loved coffee, but something about these sheer quantities made me stop and think about the nature of the vast global supply chain which makes a flat white possible, and how much each step contributes to climate change.
Indeed, the importance of understanding coffee’s impact on our climate is emphasised by recent research which suggests that demand for the drink is expected to triple by 2050. Therefore, this article examines some of the key emission-producing stages of the coffee supply chain and discusses what steps are being taken to reduce your cup of joe’s carbon footprint.
North America and Europe import two-thirds of the 9.5 billion kg of raw coffee grown annually in the fragile tropical ‘coffee belt’. The carbon footprint of a cup of coffee can vary dramatically depending on whether or not its journey from a farm in the coffee belt to a takeaway cup in, for example, London has been informed by sustainable practices. Indeed, up to 15% of a cup of coffee’s carbon footprint can come from international transportation.
The crucial choice here is between air freight or cargo ship, with the former producing 100 times more CO2 per km than the latter. I spoke to several UK-based coffee roasters, who explained that it is rare for roasters to import via air freight. They suggested that both economics and an awareness of the environmental impact of air travel inform this decision. The journey time of a cargo ship to Britain from most coffee-producing areas is roughly 3 months, presenting a challenge to roasters. But they are importing tonnes of coffee, and it is often cheaper to take this option. Equally, they said that it would be unconscionable to import the amount of coffee they do via air freight, although evidently cargo ships are hardly good for our environment.
Once raw coffee has arrived in the UK, it is roasted into the coffee beans we would recognise. The roasting process is not only energy intensive, but can also produce harmful particulates, carbon dioxide and monoxide, and nitrous oxide.
However, recent technological development has greatly reduced the quantity of emissions produced during roasting. Newer coffee roasters are far more efficient than their older counterparts, and many roasters have recently chosen to upgrade due to high energy prices. Gas abatement systems, such as catalytic converters, are also now more common and help make the gas by-products of roasting less harmful.
In the Café
The process of making espresso, the concentrated coffee drink which forms the base of most drinks served in a café, is very energy intensive. For instance, commercial espresso machines often constantly hold more than a litre of water at boiling point, and a smaller amount of water at around 120 ᵒC for steaming milk. And a commercial espresso machine stays on 100% of the time because they take a long time to warm to their optimum operating temperature. Hence, this part of the supply chain is a key area where sustainability gains can be made, with 70% of the CO2 emissions produced after coffee arrives in the UK coming from this final step.
Commercial espresso machines have always been efficient, for instance by keeping boilers highly insulated. Yet an increased focus on sustainability amongst consumers has led to innovation in this area. At the cutting edge is Victoria Arduino’s Eagle One. A prominent coffee expert who was part of the design process, James Hoffman, stated that they had one word in mind when designing the Eagle One: ‘sustainability’ (both in the environmental and economic sense).
Most notably, using an innovative new method of heating the brew water (the water that makes your espresso), the company managed to reduce the brew boiler from the standard litre or so, to only 150-200 ml. In doing so, they drastically reduced the amount of energy being wasted holding a large amount of water at almost boiling. This, along with other innovations, such as recycling heat from wastewater and a waste-reducing ‘auto flush’ system, means that the Eagle 1 uses a staggering third less energy than its competitors. It would be highly surprising if competitors, such as the ubiquitous La Marzocco, were not already developing their own more sustainable machines in response to the Eagle 1.
It is evident, then, that at the three stages of the coffee supply chain highlighted here, efforts are being made to reduce carbon emissions. This is significant, as recent research suggests that following sustainable practices across the coffee supply chain and using non-dairy milk reduces the carbon footprint of a latte from 0.6 kg CO2 to 0.2 Kg CO2.
These changes are critical, and it is encouraging that an increased focus on sustainability amongst consumers is driving change in the coffee industry. And cafés that source their coffee sustainably should proudly advertise this. It would be helpful, for instance, to see the carbon footprint of your coffee advertised alongside its price.
Anyway, consumer practices may soon change regardless; experts predict that the land suitable for growing coffee will reduce by 50% by 2050 if climate change cannot be arrested. Change is coming, whether the industry and western consumers are ready for it or not.