Innovation Is Transforming Retail At The Shelf Level — But What’s Powering The Shelf?

After years of shaking up every vertical from print media to automotive sales and financial services, digital transformation is finally becoming an imperative on supermarket and retail shelves.

According to McKinsey, personalized brick-and-mortar experiences are the next frontier in digital. Smart shelf technologies represent that move toward transformation, bringing the power of big data and automation to grocery and retail stores.

Smart shelf solutions offer game-changing promise for retailers: sensors that track inventory levels and prevent theft; electronic price tags that retailers can update with a mobile app; and detailed analytics that support the kind of omnichannel, seamless experiences customers get when they shop online.

However, smart shelf solutions aren’t without their challenges — particularly where power is concerned. Smart shelves need power, but what is the best way to deliver it?


An Overview Of Smart Shelf Technology And How It Works

Smart shelves are systems made up of a variety of technologies designed to help retailers make smarter inventory planning and merchandising decisions, automatically sense stock levels, and collect customer data like foot traffic patterns, shopping behavior and more.

Retailers might also use digital signage technology to market to shoppers in real time, while electronic price tags ensure that shelf-level pricing is always up to date.

Smart shelves are enabled by a few different types of IoT technology, including:

  • Electronic Shelf Labels (ESL): Using ESLs,  retailers no longer need to change prices manually when items go on (and off) sale, eliminating the need for manual price checks. They also enable retailers to reduce waste by strategically pricing products approaching expiration.
  • Digital Signage: Digital signs are gaining traction indoors these days, and serve as a form of in-store digital marketing for grocers, allowing them to showcase promotions, highlight new products, or provide cooking inspiration for seasonal or unusual ingredients. For instance, large digital “end cap” signs can be placed at the end of every aisle to draw attention to a particular promotion.
  • Cameras: Placed strategically, cameras can be used to track inventory levels as well as to gain a deeper understanding of how individual shoppers behave, monitoring how they move through the store and where they spend the most time. Cameras can also help facilitate cashierless shopping akin to what you’d see in Amazon Go stores.
  • Weight sensors: Weight sensors can detect when a product is removed or replaced, helping to track stock levels and reduce theft.
  • RFID Tags: In a supermarket setting, RFID tags help stores manage and track inventory and can alert store associates when an item runs out or someone puts an item in the wrong place.

How Smart Shelves Are Changing In-Store Experiences On The Floor

Supermarket retailers have long struggled to deliver relevant information to shoppers at critical decision points and make data-driven decisions about inventory management and merchandising.

Smart shelf technology can also interact with customers via smartphones. For example, sensors embedded into shelves can detect when a customer is approaching, and can be used to offer promotions in real time based on a customer’s purchase history.

Some solutions include a shopping list feature designed to help consumers find the items on their list for example, a flashing LED light that helps shoppers locate a particular part in a hardware store.

Despite privacy and data collection concerns, smarter grocery stores might provide convenience and personalized offers that make the trade-off worthwhile. Per PwC research, 63% of U.S. consumers are open to sharing data in exchange for something they value. On the retailer and manufacturer side, smart shelf tech can offer a wealth of insights. Leading solutions use a combination of cameras, sensors and machine learning algorithms to anonymously capture shopper data as they move throughout the store.

Retailers receive reporting and analytics they can use to inform the decision-making process, while demographic criteria (detected via sensors and cameras) like age, gender and ethnicity can automatically trigger content at the shelf level for a more personalized experience.

Solving The Smart Shelves Power Problem

From the digital end-caps and sensors to the cameras, LEDs, and WiFi connectivity bringing the “online” experience into the real world all of these pieces of digital equipment require power.

Unfortunately, traditional solutions like batteries and hard-wiring add new labor costs and logistical challenges to the fold. For example, ESLs run on coin batteries, which typically need to be replaced every five years or so — although batteries tend to wear out faster depending on just how often prices are updated.

While five years seems like a long time, the issue is maintaining a replacement schedule for a large supermarket like Walmart that easily has 50,000+ ESLs running simultaneously.

Assuming we’re dealing with 50k units, that means the store would have to replace nearly 30 ESL batteries each day — with one outage here, another there, a time-wasting cycle we refer to as the “popcorn effect.” So batteries are probably out as a viable solution.

Alternatively, running power cords to every shelf in the supermarket is no good either. For one, it’s expensive. Running cords from ceiling to shelf can cost up to $5,000 per drop. This type of installation is often done at night or during off-hours, which also results in increased overtime and supervision costs that can add up over time.

Additionally, this setup can cause safety hazards (hello, dangling cords) and well, it’s ugly. It’s also worth noting that hard-wired cables don’t support easy store reconfiguration. This means that changing the layout of the store for seasonal or short-term promotional displays becomes an expensive, time-consuming activity.

Wireless Power Helps Smart Shelves Realize Benefits

Long-range wireless solutions stand to play a key role in making the future retail store a practical reality. Here’s how it works: A wireless power transmitter sends safe, infrared beams to a receiver (typically embedded in the device to be powered), and a small photovoltaic cell in the receiver converts the light to electricity. This concept is similar to solar panels converting sunlight into electricity. Infrared beams can travel with little degradation over a distance, efficiently, safely and reliably providing wireless power across a room to the device, eliminating the need for power cords or batteries.

Wirelessly delivering power from transmitters on the ceiling of the store to small receivers on the shelf eliminates costly power installations and the over-reliance on batteries.

That said, there is the question of whether one should power the individual devices on the smart shelves or, on a more holistic level, power the entire shelf.

Delivering power directly to individual devices offers flexibility to retailers in that each device functions as a separate entity. The downside here is cost. Again, if we look at the ESL example and choose to deliver wireless power directly to each ESL, we would need 50k+ wireless power receivers. Let’s face it: this could wipe out any of the cost-saving benefits of ESL adoption.

In contrast, if we delivered power to the shelf level, we would need far fewer receivers, but we would also need to ensure that the shelves are set up to distribute power to all connected devices. This can be done using short wires or by installing low-voltage ‘power rails’ on shelves.

Yuval Boger is the CMO of Wi-Charge, a provider of long-range wireless power. Boger is an expert on wireless power technology and has experience working with large hotel chains implementing this technology. He holds an MBA from the Kellogg school at Northwestern University and a M.Sc. in Physics from Tel-Aviv University.