Prefer to shop from the comfort of your couch or home office? Turns out, you're doing the environment a favor. A recent study from Carnegie Mellon University has found that shopping online - especially from a retailer that ships products directly from wholesalers, rather than collecting and sorting items at a warehouse - can cut out 35 percent of the CO2 produced by an average trip to the mall.
Much of the CO2 that results from purchasing an item comes from a consumer's trip to the mall. Researchers compared an online and mall purchase of a flash drive - calculating the drive's emissions from manufacturer to final destination in the consumer's home - and learned that online retail is more efficient in pretty much any scenario, even when the item is being air shipped overnight (but barely - it's basically a draw). Both e-commerce and traditional shopping were evaluated for the energy used by computers, customer transport, product transport, retail stores, warehouses, and packaging.
The company that CMU used as its example, Buy.com, has an especially efficient model. Buy.com eliminates the processing warehouse that many other online retailers like Amazon use, and instead ships products directly from the distribution partners, cutting out the energy used in sorting, processing, and repackaging in warehouses. Online shopping uses the most energy in last mile delivery (meaning the UPS truck) but the researchers found that delivery still used less energy per package than a typical trip to the mall.
If you live close enough to take public transportation to a mall (or even walk), you're better off doing that. Auto emissions from trips to shopping centers make up such a large portion of the traditional retailers' share of CO2 that, if eliminated, you'd consume less energy than you would shopping online. But if you live more than a couple of miles away from a mall, you're better off curling up on the couch with a laptop and clicking away.