By Peter Day Presenter, BBC Radio 4 and BBC World Service

Ocado promises customers a one hour delivery window

The underlying argument of this series of columns is that business in the 21st Century will have to wake up to a series of imperatives that have been latent but obscured until now.

The vital idea is that the internet has radically changed the way millions of people communicate, interact and reconfigure their relationship to traditional business entities.

Some companies have grasped this, and in Britain we have at least two remarkable examples.

They are both reminders that getting the shops right and the prices right are no longer enough.

Consumers want more, and the internet has made available a potent shopping alternative.

One of the first companies to recognise this theoretical potential was a lavish Californian start-up called Webvan: home delivered groceries from lavish specially built warehouses using specially designed vans.

Webvan spent $1bn (�560m) of other people's money on its launch in one of the richest, most tech savvy and most self indulgent regions of America. It crashed spectacularly in 2001 after only a year of operation.

With the wisdom of hindsight, the critics all said it never stood a chance.

High technology

But, undaunted, in Britain Ocado launched a similar operation in the south of England three years ago.

Ocado currently works from a single giant warehouse

Ocado is a fascinating operation, dreamt up and run by three dazzlingly bright 30-somethings, ex-investment bankers from Goldman Sachs in London.

Much of the money was provided by the ultra-conservative workers cooperative the John Lewis Partnership.

John Lewis owns the small Waitrose supermarket group, mostly restricted to the south of England.

Ocado spent up to �100m building a tremendously complex warehouse, a vast aircraft hanger on the redundant Hatfield airport.

Inside this enormous space, thousands of internet orders are serviced by pickers marching out across the acres of shelved goods.

Shelving rolls out into the distance; conveyor belts whiz deliveries to their allotted slots.

With considerable attention to nitty-gritty detail, similar products are not stored side by side, to reduce the chance of mispicking, which still has to be done by people, not machines.

The orders are stacked, packed into pods that attach to big trucks, and then transported all over the South East of England to car parks where the eight pods are slotted onto individual delivery vans in order for street-level deliveries.

Each is timed to a one-hour agreed delivery window, and aided by satellite guidance to get the drivers through the complexity of the middle class suburbs.

'Rampantly successful'

So far Ocado has eaten up �200m of investment, and now that it is making weekly profits most weeks, it's almost ready to float on the London stock market with an expected value of some �350m - making three Goldman Sachs investment bankers very rich indeed, and bringing sighs of relief to the normally risk averse John Lewis people.

Tesco's home delivery service picks up from its local stores

Meanwhile, the rampantly successful Tesco has built itself into Europe's largest online store with quite a different model.

Tesco's internet site sends the orders to your nearest real-life store, where pickers go down the shelves in a race with store shoppers who may get to the last item before them - by contrast, the Ocado computer can in theory allot items as the orders come in, with far less chance of disappointment when the order arrives.

Then the Tesco vans take the orders out locally (with a two-hour delivery window), just like the grocery bike delivery boys who served my mother 50 years ago.

So here in Britain we have two completely different e-commerce models battling for supremacy. I think they both may win.

Tesco has the physical stores, and a dash, muscle and management that gives it tremendous plausibility.

Hassle-free

But for all the vast costs and risk of Waitrose's superwarehouse model, it is far cheaper and faster to invest millions in Ocado than to buy sites and get planning permission for the hundreds of stores that Waitrose needs to become a really big player in British groceries.

One Hatfield warehouse may be expected to eventually do the business of 10 shopping mall supermarkets.

There's another thing, too. Waitrose is revered for the way it is perceived to deliver quality produce to picky consumers prepared to pay more for "better" groceries.

Waitrose has stepped outside the price-driven world that is running the British supermarkets ragged as they try to compete with Tesco's buying power.

Waitrose can afford to take home delivery seriously because it has much bigger profit margins than the other supermarkets. The Goldman Sachs entrepreneurs found an obvious but absolutely plausible partner.

Both Tesco and Waitrose have learnt very early how to do what most companies will have to do to keep their costumers in the 21st century: take the hassle out of shopping. Carrying it out is not easy.