A Tesco.com test store in Croydon has helped the supermarket chain up its sales by 30 per cent in the last year to hit £1bn for 2006.

The Factory Lane store, which exists solely to fulfill online grocery orders made by customers, is one of only a few locations thought suitable for the scheme and as a result has proved very successful.

A spokesman for Tesco said: "While only a few locations are likely to be appropriate for this, it has been providing busy stores with more capacity to grow and freeing up a lot more convenient delivery slots for Tesco.com customers."

Overall, Tesco has reported profits of £1.1bn for the first half of the year and a spokesman said the success of the Croydon store is likely to increase the number of online grocery stores nationwide.