The Deutsche Post's DHL delivery company estimated that shipping a package results in fewer than 500 grammes of greenhouse gases emitted into the atmosphere.
With 500 grammes a modern car can travel 3.5 kilometres, but most shopping trips in Germany are around six kilometres, according to the Environmental Institute in Darmstadt.
So on the surface it seems that internet shopping is greener.
But the paper noted that many internet products are bought only after shoppers have first combed the brick and mortar stores. Items like bicycles, computers and other electronics are normally first tested in actual shops – and then only purchased online because the prices are better.
For a correct environmental accounting, though, these store trips, often made with an automobile, need to be taken into account.
“Just because e-commerce is booming and more and more goods are being purchased online does not automatically mean that customers are forgoing their car use,” said Dieter Urbanke, head of Hermes Fulfilment, a logistics company owned by the Otto Group.
On top of this the environmental calculation has to take into account when the delivery person comes to the door and no one is home and there isn't a neighbor who is willing to accept the package.
Hermes, for example, will make up to three attempts – with an additional 500 grammes of greenhouse gasses being released into the atmosphere per attempt – before leaving the package at the nearest Hermes Package Station, where the client has to pick it up.
DHL will only make one effort before it parks the package at a nearby pick up station. Clients usually come to pick up their goods with a car, the paper wrote.