The study compared three delivery methods: traditional “bricks-and-mortar” shopping, “bricks-and-clicks” where consumers purchase products online and the last leg of their distribution is conducted from a retail shop, and “pure players”, where consumers purchase online and their distribution bypasses a physical retail unit, instead being conducted by a parcel distribution centre. The pure-players supply chain is the only option for online-only retailers. The median total GHG emissions per item delivered via pure player were 0.18kg CO2 equivalent, almost twice as high and bricks-and-mortar retailing at 0.10 kg CO2eq/item and 2.5 times greater than those of bricks and clicks 0.07 kg CO2eq/ item.
This research emerges amid growing concerns about GHG emissions and the climate crisis. Presently in the UK only 7.5% of all FMCGs sold are purchased online, but that proportion is expected to grow to 12% by 2025. This research contradicts past studies which have indicated online shopping may be less carbon-intensive that traditional bricks and mortar shopping. This is because this research takes into account the purchasing habits of consumers. When purchasing from a local shop consumers are more likely to make a large order, reducing the carbon footprint per item. On the other hand, while purchasing from online-only stores, consumers are more likely to order individual items.
However, the scope of this research is limited by the complexity and diversity of supply chains, even within the FMCG sub-section of the retail market. The largest proportion of GHG emissions within pure players supply chains came from the last mile transport, which takes the product from a parcel distribution centre to the consumers home. This transport is highly dependent on the density of consumers in the delivery region, and therefore there is a lot of variability in GHG emissions depending on region. This was mitigated to an extent in the research by using data from multiple regions in order to generate figures broadly representative of the UK.
Increasing popularity of online shopping may result in a rise in the pure-player supply chain, despite it being the most carbon-intensive. To combat this issue the researchers found substituting delivery vans with electric cargo bikes reduces overall GHG emissions by 26% for pure-player supply chains. They also advocated trip-chaining to reduce GHG emissions by bricks-and-mortar shoppers, for example by attaching shopping to a larger trip such as travelling home from work. Furthermore the GHG emissions of online shopping can be reduced by avoiding fast delivery, as it reduces the emissions efficiency of delivery routes chosen. This places environmental sustainability at odds with convenience for consumers.