It’s difficult to assign an exact carbon footprint to the $200 billion coffee industry. Emissions tied to coffee production vary, and tossing milk in the mix drives them up. But an average cup of Joe comes with emissions of roughly 400 grams (a little less than a pound) of carbon dioxide equivalent. Fifteen percent of that is tied to the roasting process, with the rest largely coming from growing and transporting beans.
When you consider Americans consume more than half a billion cups a day, the carbon math gets more daunting.
At first blush, addressing those emissions seems like an intractable problem: Most roasting equipment runs on natural gas, which produces both carbon emissions and air pollution. Until recently, there wasn’t much demand for electric alternatives, and early electric models had a reputation for producing inconsistent roasts. By automating some of the roasting process and reducing emissions along the way, Berkeley-based Bellwether is hoping to corner the nascent e-roaster market.
Bellwether says its machines can cut roasting’s carbon emissions by 90% compared to gas-powered alternatives. Applied to a coffee giant like Starbucks, which saw 148,000 metric tons of CO2 emissions from its roasting operations in 2018, reductions would be in the ballpark of 129,000 metric tons of CO2 per year, according to Bellwether.
The electric machines also knock out a source of particulate matter produced by the methane gas used to roast coffee and by the coffee itself as it’s roasted. Because Bellwether’s machines are ventless, the vast majority of particulate matter and volatile organic compounds released in the roasting process don’t end up in the air.