The Logistics Research Centre at Heriot-Watt University
has produced a comparison of the carbon footprints of online and conventional shopping for small goods such as books, CDs, cameras and household items.
The researchers found that a typical van-based home delivery produced 181g of carbon dioxide, compared with 4,274g of CO2 for an average trip to the shops by car. An average bus trip by a shopper produced 1,265g of CO2.
In other words, the researchers conclude, when a customer drives to the shops and buys fewer than 24 small non-food items per trip, or travels by bus and buys fewer than seven items, home delivery is more environmentally-friendly.
The critical factors in the calculation, they explain, are the number of items purchased per shopping trip, the choice of travel mode, the probability of the consumer being at home to receive the goods and the way in which unwanted goods are returned. The figures quoted, for instance, make no allowance for failed home delivery or the return of unwanted products.
"While this research suggests that home delivery is less carbon intensive, neither it nor a conventional shopping trip can be said to have an absolute environmental advantage," says Professor Alan McKinnon, director of the Logistics Research Centre and one of the authors of "2009 Last Mile Carbon Auditing," a new report based on the findings. "Someone using public transport at peak times and buying goods in bulk can match the emissions per item of home delivery."
"The willingness of shoppers to combine shopping with other activities and to group purchases into as few shopping trips or online transactions as possible is clearly important to minimise the environmental impact of both conventional shopping trips and home delivery," he explained. "Online retailers and home delivery companies can also apply various measures to enhance the CO2-efficiency of their logistical operations and gain a clearer environmental advantage".
The report emphasises that both consumers and suppliers need to be better informed about the environmental implications of their respective shopping behaviour and distribution methods.
"It has long been assumed that the overall efficiency improvements inherent in e-retailing make it more planet-friendly than going out to the shops, but this factual, wide-ranging research nails the point," says James Roper, chairman of IMRWorld.org. "Now that Heriot Watt University has proven the general principle, further research into the subject of consumer goods distribution is certain to follow in order to discover precisely what aspects are more efficient and to what degree, and how still greater efficiency improvements can be obtained."
Readers can download a copy of the full report free of charge
from the IMRWorld website.