Dirty Power: A Clear & Present Danger to the Customer Experience

A leading factor in POS system failures at convenience stores is low-quality power.
power quality

Convenience stores across the United States cumulatively process up to 165 million transactions per day, according to data from NACS, the Association for Convenience & Fuel Retailing. While c-store shoppers seek a broad range of offerings, like fuel, prepared or packaged food and beverages, toiletries and beyond, there is one thing they will never want a long wait time.

Convenience stores are known for speed, with a customer journey averaging just 3 to 4 minutes from entry to departure. Waiting undermines the very purpose of the store, which is to serve customers as quickly and smoothly as possible.

A crucial component of minimizing wait times in convenience stores is optimizing the performance of point-of-sale (POS) systems. These systems simplify the checkout experience when they function properly, but can extend a wait time indefinitely if they lock up or if their communication with other digital systems is corrupted.

A leading factor in these types of POS system failures is low-quality power, a problem that plagues retail businesses of all kinds, but has an outsized impact on those reliant on transaction speed like convenience stores. To maintain operational speed and offer an outstanding customer experience, “dirty power” needs to be understood, resolved and prevented before it causes an interruption.

Power Availability Doesn’t Equal Power Quality

Seeing the lights on and equipment running is often enough to convince operators and customers alike that the power environment is just fine, but this is not always true. 

Understanding power performance begins with differentiating between power availability, the amount of time power is operating connected equipment, and power quality, a measure of a power supply’s deviations from normal sine waves. These deviations can impact overall power quality in many ways depending on the unique power environment of the convenience store.

Sags, swells, spikes and other inconsistencies that result from weather events, variable usage patterns or any number of other triggers affecting power coming into the building can cause visible failures like outages, external disturbances, or even complete lockups in electrical performance. Yet only 10 percent of these failures are immediately visible, with the rest silently distressing critical systems.

The largest, most consistent and often unseen causes of power disturbances are caused by electrical noise inside the building, emitted from each piece of nearby electrical equipment, especially energy-intensive machinery like commercial refrigerators. Electric cooking equipment, HVAC systems and even overhead lights also produce noise in the form of electrical impulses, high-frequency noise, and high-voltage transients.

Over time, these minor yet manifold blips corrupt the smooth sine wave that electrical power is supposed to travel along. These anomalies result in subsequent departures from the expected performance baselines the manufacturer originally assigned to its equipment.

Just like impurities in tap water, power inconsistencies are common. And unfortunately, commonly overlooked. Power anomalies won’t necessarily destroy equipment, but over time, can cause degradation, system lockup, and undetected data logic errors, which all contribute to the slow erosion of system components and performance levels.

These issues have a real impact on business continuity. For instance, an untreated power spike that locks up a POS system for an hour could compromise dozens of transactions and ruin the customer experience for many guests.

Convenience store customers spend a combined average of 63 seconds waiting in line and paying for their purchases, accounting for roughly a third of their total in-store time. A downed POS system can easily balloon that number, frustrating shoppers who may abandon their purchase and never come back.

Performance Slippage Disappoints Customer Expectations

POS system issues can arise even when equipment remains online, as electrical noise can interfere with data transfer and lead to logic and communication errors. The interconnection of electronic devices from order terminals to site controllers to ticket printers is crucial to providing an in-store experience on par with consumers’ heightened post-pandemic expectations.

For example, if poor power affects the communication between an order kiosk and a POS system, consumers could receive incorrect orders or lose their orders altogether. Especially with the proliferation of on-the-go and order-ahead e-commerce mingling into the traditional customer service territory, digital connectivity between systems is essential to maintaining competitive performance.

Properly protected power ensures that POS data strings are sent and received without error, whether from a direct input at the register or via connected systems like mobile or kiosk ordering, so no lockups or order detail issues occur.

As demand for immediacy and digital transformation continues, this reliability will also be crucial in outfitting today’s stores with instant pay or cashierless checkout solutions. These are potential growth areas for convenience stores, as NACS research shows 65 percent of frequent convenience store visitors indicate interest in technologies that allow them to skip checkout lines.

At a high level, dirty power can also stunt the lifecycle of POS products and connected devices. If they are consistently served high-quality power, they are much less likely to become exhausted or require repairs early on than if they run on dirty, untreated power.

Amortizing expensive equipment across two additional years is the difference between assigning 20 percent annually or just over 14 percent a year, independent of interest. That’s a big margin in a small-margin industry; and a time investment to install, calibrate and train employees to use new equipment that could interfere with customer service more frequently.

Convenient, Reliable Solutions for POS Systems  

The adverse impacts of inferior power quality on everyday equipment performance and lifespan define a fiscal responsibility for convenience store operators and managers to implement proper management solutions. While every power environment presents different needs, there are some key elements that prospects should look for in a solution to ensure consistent performance for POS systems.

The three key components that ensure a solid power quality system are:

  • A surge diverter;
  • A noise filter; and
  • A low impedance isolation transformer

The low impedance isolation transformer, while not always commonplace in power management solutions, is especially useful to complete power protection as it isolates devices like POS systems from the power source and conditioning power before it reaches the sensitive electronic components.

When employed in tandem, these three features work together to condition and provide clean power that is free from noise, voltage spikes, and common-mode disturbances (ground noise).

But what if the power goes out entirely? Generators can address that, but they take around 30 seconds to kick on. Deploying a local area UPS (Uninterruptible Power Supply) system to provide uninterrupted power, especially one that incorporates effective power conditioning and ground guard technology, bridges the gap to cut out downtime entirely.

Several devices exist and incorporate these solutions proven to protect POS performance, but ultimately, your store’s power environment should be assessed by a power professional to understand which features and solutions will be best for your equipment, traffic flow, and bottom line.

The conversation around power quality boils down to knowing what consumers want and expect in their convenience store experience. They don’t want to wait, and you don’t want to disappoint. Power viruses are curable ailments in your store that can and likely will often result in longer wait times and operational interruptions if left untreated.

Imagine being the only store on the block with power and a fully functional POS. Now, imagine being the only one without that. One of these scenarios is obviously preferable, and a key action you can take to fulfill that prophesy it is to protect your devices with power quality assurance.

David Sansenbach is national account sales manager, retail technologies at Powervar, a global provider of advanced power quality solutions. For more information, visit

Editor’s note: The opinions expressed in this column are the author’s and do not necessarily reflect the views of Convenience Store News