Shoppers need to buy at least 25 items from a website, before any environmental benefits take effect. If a consumer buys fewer items than that it would be better to drive to the shops, than rely on a lorry to make the delivery to their home.
This is the finding of the Institution of Engineering and Technology, which looked at the so-called rebound’ effects of activities that are commonly thought to be green. Rebound effects are the unintended consequences of policies.
First of all, you have to strip out those parts that are common between say, Amazon and Waterstones. They both have suppliers, who both deliver to warehouses. The next part differs, but has similar levels of fuel use - delivering packages from the warehouse to depot (in Amazon's case) vs delivering from depot to Branch (in Waterstones' case).
Prof Phil Blythe, chairman of the IET transport policy panel, which produced the report, said: “We hear a lot about the environmental benefits achieved as a result of working from home. However, on closer inspection it does appear that any environmental benefits are marginal.”
But the real difference is what happens next. In the case of Amazon, they transport your book from depot to home, along with hundreds of other parcels. Whilst it's not going to be the most direct route to your home, it's going to be part of a large optimised delivery (these guys have software to work out the best route). If you consider that a van is going to deliver to even 5 houses in the same estate, it's going to use almost the same energy than one householder will use going to town.
Maybe I'm missing something in the chain here, something that adds a whole load of extra fuel to internet use, because I really don't buy this.