Your 12 ounce latte comes with a pound of carbon emissions, just from the drive-thru.
How convenience for cars makes cities less livable for everyone, and contributes to climate change.
Last week, twitter user Maris Zivarts posted this telling image of 20 car queue wrapping around the block of a Starbucks, all lined up to go through the store’s drive-thru. It shows how the store’s driveway and parking lot taking up vastly more space than the store itself, and how the backup from the drive-thru window spills out onto adjacent streets, creating congestion and a safety hazard for others.
As Zivarts observes, 20 people showing up at a coffee shop on foot, by bike or transit is no problem. The same 20 headed for the drive-thru window is a disaster. It’s clearly a blight on the neighborhood as well.
And more than that, it’s bad for the environment. Those cars idling while they wait in line are burning gasoline and creating pollution, including greenhouse gases. How much, you might ask? Well, we’ve studied queueing and service at coffee shops before (to create our Cappuccino Congestion Index), so we have a pretty good handle on this. We would estimate that the average wait would an average of and ten minutes to handle all the cars in a queue like this. (This assumes that the store can produce an order about every 30 seconds).
The US Department of Energy tells us that a typical large US car burns about a third of a gallon per hour at idle. A gallon of gas produces about 20 pounds of carbon when burned. So that means that in ten minutes of idling would produce about a pound of carbon (10/60 * 20 * .33 = 1.1). So, in addition to their twelve-ounce latte, each customer is producing another 16 ounces or so of carbon to be added to the global total, just from the time spent idling in their car, waiting to be served their coffee. And, of course, this doesn’t count any of the emissions from driving to and from the coffee shop to get served, which by the same math works out to about another pound per mile.