The company, which made a profit of £12.2m in the last financial year, expects sales of well over £10m every week in the run-up to the festive period. Last year in the seven days before Christmas Tesco.com vans were making a delivery every three seconds, with sales of more than £12m.
The online grocer is adding extra capacity on its IBM and Dell servers, increasing its Microsoft SQL database size and boosting telecoms capacity to cope with the demand, said Mike McNamara, chief technology officer at Tesco .com.
"We completed our Christmas planning in July and are now adding the technology," he said. "We increase our capacity all the time as we are a growing business, and we will retain most of it after Christmas, maybe with the exception of telecoms."
Tesco.com is also investing heavily in mobile technology for employees who pick goods in Tesco stores and its van drivers, in order to ensure accuracy of home delivery orders placed via the website.
"We are trialling mobile devices in a number of stores and with some of our drivers," he said. "The applications are Windows CE-based, but we have not decided on the hardware as yet."
As well as focusing on back-office IT systems, Tesco.com is implementing new technology to improve customer service.
Earlier this month, the company went live with new intelligent search and navigation technology on the Wine Warehouse section of its website. The Infront software, from supplier Endeca, will be rolled out to the other non-food parts of the business, such as books, flowers and electricals, in the coming months.