Introducing the Clockwork Reliability Index: A New Standard for Measuring EV Charger Performance

The EV industry has made impressive strides in deploying more charging infrastructure—but availability doesn’t always equal reliability. Drivers still routinely encounter broken stations, confusing interfaces, or chargers that simply don’t deliver a full charge.

Yet, many networks continue to report uptime above 99%. This figure, while accurate by some definitions, often fails to reflect the actual experience of drivers. That’s the problem we set out to solve at Clockwork.

You can't fix what you don’t see.

99% uptime doesn’t mean 99% success—and without a full picture of what's really happening at the charger, the problems persist.

What is the Clockwork Reliability Index?

The Clockwork Reliability Index is a site-level performance score based on what really matters: whether drivers can charge successfully. At full power. The first time they plug in.

It moves beyond narrow definitions of uptime and offers a more complete view of how chargers perform in practice. The Index highlights the gap between what networks report and what drivers experience.

Why This Matters

EV drivers need stations that work—consistently and predictably. Better charging reliability isn’t just a nice-to-have; it’s a requirement for continued EV adoption.

Without real insight into the performance of charging networks, we risk undermining the trust that drivers, regulators, and investors place in public infrastructure.

How It Works

• The Clockwork Reliability Index is calculated using historical OCPP data and driver-based signals.

• It reflects activity over a predefined period at the site level (preferably 60+ days), identifying chronic performance issues.

• The score is based on measurable indicators such as charge session failures, authorization problems, communication faults, etc.

• Reports include a breakdown of how the score is calculated, offering full transparency into the calculation behind it

The goal is to provide a clear, objective view of network performance that drives action—whether that’s identifying underperforming sites, streamlining operations, or informing investment and funding decisions.

What It Means for Fleets + Charge Point Operators

If you operate a charging network, unreliable stations are more than just a nuisance—they’re costing you:

• Lost revenue: Every failed session is a missed opportunity. When chargers are down or underperforming, you’re leaving money on the table.

• Brand damage: Drivers remember failed sessions. Poor reliability erodes brand trust and pushes users to more dependable networks.

• Operational inefficiencies: You’re scaling fast. The Index provides the insight needed to scale confidently—without hiring an army of support staff. By knowing which stations need attention, your team can work smarter and cover more ground.

This isn’t about finding fault. It’s about giving operators the data they need to succeed, build trust, and grow efficiently.

Who Else Benefits

• Regulators and funding agencies who need clear, trusted data to make decisions.

• EV industry partners and developers who rely on dependable charging for their operations and business models.

Moving from Guesswork to Clarity

You can’t fix what you don’t see. By using real-world performance data, the Clockwork Reliability Index offers a practical, site-specific view into how charging stations are working - and where they’re falling short.

If you manage charging stations, the Index gives you the insight needed to take meaningful action. And, if you’re an investor or policymaker, it’s a way to ensure that the infrastructure you funded is delivering on its promises.

Learn More

Visit clockwork.energy/reliability-index to see a sample index and connect with our team. You can request a Clockwork Reliability Index report for your site or network and start building the data foundation needed for a better EV charging future.