Step by step: The quest to reduce the carbon footprint of espresso
Jenna Gottlieb investigates how innovation in espresso technology can mitigate some impacts of climate change and make coffee less carbon intensive than ever before.
When consumers visit their favourite coffee shops, they’re more likely to ask the barista about a coffee’s origin or roast profile than its carbon footprint.
But they should. The coffee industry is predicted to suffer huge losses in production capacity if climate change continues to occur. A recent study estimated that around half of the land currently used to produce high-quality coffee could be unproductive by 2050.
According to the study, which analysed the effects of climate change on crucial tropical crops, Brazil will see its arable land decrease by 79%. That’s a damning premonition for a country that produces more coffee than any other.
Deforestation and the spread of disease are other factors that are linked to climate change. Consumers and businesses alike are beginning to realise that we may not be able to take our coffee for granted for much longer.
Historically, espresso machines have been significantly energy-intensive products, but modern designs incorporate energy-saving technology that dramatically reduces their demand for electricity.
Subsequently, we’re seeing a gradually decreasing carbon footprint per cup of coffee. Looking ahead, it seems that there are several ways to reduce it further – without compromising on quality.
How much carbon dioxide does a shot of espresso actually produce?
Carbon dioxide (CO2) is a greenhouse gas that directly contributes to the warming of the planet. Although no actual CO2 is released when a barista pulls a shot of espresso – aside from any gas trapped within the coffee beans – the energy required to do so indirectly emits CO2 into the atmosphere.
A carbon footprint is the amount of CO2 released into the atmosphere as a direct or indirect byproduct of an event or the manufacturing of a product. It can be calculated for virtually anything and is measured by the number of tonnes of CO2 emitted annually. It also takes other harmful emissions like methane into consideration.
In origins like Vietnam or Brazil, it’s estimated that growing a single kilogram of arabica coffee and exporting it to the United Kingdom produces greenhouse gas emissions equivalent to an average of 15.33kg of CO2.
According to a report from University College London, changes in production methods, transport methods, and consumption habits can all contribute to lowering this figure.
At the cafe level, the average cup of coffee contains about 18g of green coffee, meaning that 1kg is equivalent to 56 espresso shots. Just one espresso shot has an average carbon footprint of about 0.28kg, but it could be as little as 0.06kg if grown, processed, and shipped according to the report’s sustainable guidelines.
When preparing an espresso shot, several factors go into extracting the perfect espresso, all of which have their own carbon footprints. For instance, grinding finer increases the pressure required to brew espresso, which is more energy intensive.
Baristas and home consumers also require scales, portafilters, tampers, filtered water, and a quality espresso machine. Manufacturing these products results in yet more emissions.
What can be done to reduce the carbon footprint of espresso?
According to the aforementioned report, an estimated 70% of carbon dioxide emissions are attributed to the brewing stage of coffee consumption, mainly due to the significant energy used by automatic coffee machines.
“This energy use could be reduced by using more efficient water using technologies – although this is largely in the hands of the consumer – and the design of more efficient coffee machines,” the report adds.
Indeed, energy-efficient machines play a crucial part in reducing coffee’s carbon footprint.
Motion-sensor coffee machines, like the smart devices developed by Carimali, detect the presence of anyone in proximity to the device. When there isn’t anyone nearby for more than a specified amount of time, it automatically switches off its heating elements, saving energy.
Another example is Heylo, a new coffee machine manufacturer that has developed a boiler-free system designed to rapidly heat small quantities of milk or water for coffee drinks. The system heats liquid on demand by channelling them through conductive metal tubes surrounded by electromagnetic induction coils.
When it’s not actively brewing, the only power used by the machine is for its digital touchscreen.
Both at home and in the café, consumers can take control of their own carbon footprints by opting for plant-based milks in their drinks. Dairy milk is by far the most carbon-intensive milk option on the market today.
“Adding milk significantly increases the carbon footprint [of coffee],“ says a report from the University of Oxford. “For example, for conventional production of coffee beans, the carbon footprints for one serving of caffe latte, flat white, and cappuccino are 0.55, 0.34 and 0.41kg CO2, respectively.”
That’s significantly more than the 0.28kg per shot of espresso reported by University College London, and if the coffee industry is aiming to get that number below 0.1kg per shot, there is a lot of work to be done.