'Christmas slots went in five hours': how online supermarket Ocado became a lockdown winner

For years, it never made a profit - despite having bigger warehouses and better tech than its rivals. Post Covid-19, can Ocado go global?

Ocado's warehouse in Erith, 15 miles east of London on the Thames estuary, is staffed by 1,050 personal shoppers". Outnumbering them are 1,800 robots the size of small washing machines.

You see them by climbing to the top level of the vast warehouse - at 564,000 sq ft, it is more than three times the size of St Peter's in Rome - where a sign tells you that photography is strictly prohibited. The online supermarket is paranoid that rivals will glimpse the technology it believes to be revolutionary.