Previous analyses haven’t agreed on whether online or in-store shopping is better. In fact, some studies have found that online shopping has a lower impact, because it saves the emissions associated with driving your car to the store (95 percent of Americans drive to go shopping). But this benefit can vary, or even disappear, depending on how fast we want that TP to arrive. And if you’re shopping in real life, factors like how you transport those items, how far you travel, and how much you buy at once all affect the carbon footprint of your purchase. “There have been some contradicting results, with some saying online shopping is better and some saying traditional shopping is better,” says Shahmohammadi. So he tried to settle the debate with an approach that showed how likely one option was to be better than the other. Shahmohammadi and his team compared three shopping styles: traditional in-store shopping, online ordering from a physical store (which they called “bricks and clicks”), and ordering through an online-only retailer. For every variable in their computer models, like trip distance to stores or the number of items purchased at once, they used a range of values and ran different simulations to figure out how variable the outcomes might be. Making lots of trips to a physical store would increase the footprint from driving, for instance, while making bulk orders online could decrease the impact of shipping. They also considered the weight and volume of 2,900 common products, like shampoo, toothpaste, cleaning products, and shelf-stable foods. Nearly two-thirds of the time, bricks and clicks shopping resulted in fewer emissions per item than in-store shopping—and was better than online shopping 97 percent of the time. In-store shopping had fewer emissions than online-only 81 percent of the time. In other words, ranked from most to least emissions, the results were: online-only retail, in-store shopping, and online shopping from a physical store. E-tailers performed badly for a couple reasons, explains Shahmohammadi. For one, people tend to buy a smaller number of items at a time, enabled by free shipping. Even when they buy a big batch at once, those goods might come from many suppliers and are therefore shipped separately. And each of those items comes in its own cardboard box. There’s a lot of carbon emissions to unpack there, from the trees involved in manufacturing those boxes to the direct pollution from the delivery trucks. Meanwhile, many of the physical stores that offer online services have a minimum purchase value required for free shipping, so people tend to buy more at once in bricks and clicks shopping. This reduces the packaging and delivery emissions per item. Also, with slower shipping, there’s less pressure for delivery trucks to hit the streets when they’re only partially full. Consumers can lower their impact in a few ways. Across all forms of shopping, buying more things at a time lowers greenhouse gas emissions compared to buying them on separate trips. “What we know for sure is that when the basket size is larger, then your [environmental] footprint will be smaller,” says Shahmohammadi. Jaller adds that you can consider a slower shipment option, which allows e-tailers to be more efficient in deliveries. Also, try to avoid making so many returns of products, which further jack up the impact. “If customers don’t change their behaviors, it’s a lost fight,” Jaller says. “We have to be conscious of how we use this [online shopping] privilege.”
