Online sales are increasing and so is customer satisfaction, says Tesco, the largest supermarket chain in the UK. In its interim results for the 26 weeks to August 29 the retailer reported group wide growth.Tesco.com, the online grocery shopping service, reported an 11 per cent increase in sales, reaching a sales value of \u00a31.0 billion. Tesco Direct, the non-foods online service saw its sales increase by 29 per cent. The company said that customer churn was decreasing and its call centre is receiving fewer calls.UK like-for-like sales from June to August grew by 3.1 per cent. Group sales rose by eight per cent. Tesco has been under pressure from market rivals Sainsbury's and Asda and analysts today reported that its share of the UK grocery market fell from 31.1 per cent to 30.9 per cent.Tesco recently implemented the CA EcoSoftware monitoring platform to improve its monitoring of carbon emissions across the retail chain, replacing a spreadsheet method it had previously been using.Sir Terry Leahy, chief executive at Tesco told the Today programme on BBC Radio 4 this morning that the company was well prepared for an improvement in the economy and that they were expecting a "slow and steady" economic recovery and he said consumers were gaining confidence and spending again.