‘Dark stores’ are the massive facilities behind online commerce – but members of the public aren’t allowed in. How do they work? Chris Baraniuk finds out on a behind-the-scenes tour.

Occasionally, people turn up at the 120,000sqft, warehouse-like ‘store’ in a business park on the outskirts of Nottingham. After all, it is an Asda: the British supermarket retailer known for selling every product from mattresses to microwaveable meals. But would-be shoppers are quietly turned away. This store, like all ‘dark stores’, is a place where supermarket employees only – called ‘pickers’ – collect the items for people’s online grocery shopping and load them into delivery vans. Members of the public never see inside.

In an age when online retail has revolutionised consumer expectations, dark stores are just another example of how traditional businesses like supermarkets have had to adapt. But what goes on inside these mysterious, box-like buildings? And what have supermarkets learned in their attempts to woo more customers to their tills – both online and on the street?

A surreal supermarket

The Asda dark store is laid out like a sort of mock supermarket. There are aisles, but they are wider and more functional than in your local branch. No signs or frills brighten the shelves; the crates full of produce are marked with barcodes and identity numbers. Pickers trot up and down with ‘totes’, empty plastic boxes that eventually end up at a customer’s door, and fill them with the requested items. What they’re doing, essentially, is the manual part of a weekly shop – but on behalf of the customer, who simply receives the delivery. The physical activity of shopping itself has been outsourced.

The physical activity of shopping itself has been outsourced

There is some ambience, though. The radio is on and plays across the whole dark store. The store’s manager Richard Jackson explains that they used to broadcast Asda’s in-store radio station, Asda FM. But there was an interesting development when they decided to let employees choose what station to listen to instead: productivity went up 5%. The change stayed in place.

A veteran retailer, Jackson is hugely enthusiastic about the operation that he runs. Crisps, he notes, are big sellers. He points to one brand. “Quavers,” he says, referring to the deep-fried potato snacks. “We can do a pallet a day.”

As well as rooms kept frozen, chilled or at regular temperature, there are small kitchens where employees bake bread, fillet fresh fish and prepare pizzas – just like the specialist counters in public supermarkets. The pizzas, notes Jackson, can be wildly popular. When the television show X-Factor broadcasts, order numbers jump into the hundreds, he says.

Trying to meet – and predict – customer expectations is Jackson’s job. Jackson knows, for instance, that all of the children’s nurseries in a nearby county are open after the holidays, so he’s been preparing extra orders of fruit and milk.

A supersized struggle

But getting customers to keep coming back is the real challenge. Still gigantic in retail terms, the profit margins for supermarkets have recently been falling. The once-unflappable British chain Tesco has been forced to close stores and lay off thousands of staff. Meanwhile, customer loyalty is in tatters and loyalty schemes – once highly lucrative – are adding little to supermarkets’ profits.

Once customers start ordering online, they expect the service to be seamless

But supermarkets which have opened dark stores, click and collect locations and other schemes in a bid to get customers’ online shopping to them faster – and to keep customers loyal – have discovered the logistical challenges of delivery. Once customers start ordering online, they expect the service to be seamless. Parents will order school uniforms at 11pm and expect them to be delivered first thing the next morning, explains Jackson.

As a result, the whole dark store operation is constantly being streamlined to run as smoothly as possible. The pickers, for example, are aided by a new highly automated loading machine: it tracks barcode-stamped totes for each order and sends them to the right loading bay for the waiting vans.

This is the future

The pickers themselves carry hand-held devices, telling them which aisle to go to next for an ordered product. The instructions are organised to give them the quickest route through the store. And only the most essential information is sent: uploading and downloading pictures of products on these devices takes a few seconds longer, explains Jackson.

Picker Jamie Wigfield has worked here for about two years. “There’s a lot of pressure, but it’s a very relaxed environment, as well,” he says. Looking around at the strangeness of the facility, he smiles. “This kind of thing is the future,” he says.

Questionable convenience

Although dark stores arose as a way to make shopping more convenient, many customers find that staying at home to meet a scheduled delivery is the opposite. Some prefer to be able to collect an item themselves on their way home from work. Amazon has its version of the scheme with Amazon Locker; in the United States, Walmart is experimenting with pick-up locations.

Perhaps the supermarket will return to the days of stocking fresh produce only

Most of all, the idea of handing your weekly shopping over to a stranger doesn’t suit many people. “Customers like to interact with the product, especially fresh food, so they can look at it and check it,” says retail commentator Clare Rayner. Perhaps the supermarket, which sells almost anything, will return to the days of stocking fresh produce only. Then again, by that time Amazon Fresh could have conquered the world.

The biggest challenge, however, may be the increasing expectations – and the diversity of expectations – of today’s customers. Some like home delivery, some don’t. Some like picking their fresh products in person, some aren’t bothered. Some love self-checkout machines, others loathe them. The result? The no-nonsense, self-service ethos that made supermarkets profitable in the first place has begun to evaporate.

At the dark stores, for now, picking and processing goes on. Jackson shows off a system where employees decide how to substitute items if something a customer has ordered isn’t available. It’s important to try and substitute something that won’t cause disappointment. The strange part, though, is that consumers seem to think that the same picker does their shopping every week for them, says Jackson. They expect the picker to know what they themselves would choose.

The task, then, is to assume the mentality as well as activity of the high street shopper, who now simply orders their groceries from their computer, phone or tablet. It’s a funny delegation of duties.

“The best pickers,” Jackson comments, with no hint of irony, “are the ones who go shopping.”

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