And that’s a great advance in reducing the number sent to landfill sites.
However researchers at Cardiff University have found that offering this discount had no effect.
But charging an additional 25p per cup increased the usage of re-useable cups by 3.4%
And if you displayed environmentally friendly messages and provided some free re-useable cups the use of such cups increased by 12%.
This is a good demonstration of behavioural economics. People are more sensitive to losses than gains when making decisions. Charging 25p more is seen as a loss and people are more sensitive to that than saving the same amount.
“If we really want to change a customer’s behaviour then a charge on a disposable cup is more likely to be effective” said the author of the research report.
Many people might find it difficult to remember to take a re-useable cup with them. I have one in my car but hardly ever use even when visiting Costa at my local Tesco (partly because I don’t think Cappuccino travels well).
Last year Starbucks temporarily doubled the discount to 50p but it only increased the use of re-useable cups by 0.2% up to 1.2%.
After the success of charging people for plastic bags in shops it’s worth considering a similar move with coffee cups.