Induction Powered Electricity Current Monitoring A Self-Powered Sensor That Reads a Wire's Current

This patent describes an electricity monitoring device that powers itself from the very wire it is measuring, harvesting energy by electromagnetic induction so it needs no battery change or external supply. It comes from Vutility, Inc., an American company that makes real-time energy metering hardware.

The Problem

Knowing how much electricity a circuit is using is the first step to managing energy in a building, but installing meters is often harder than it sounds. Traditional current sensors need their own power, which means running a supply or fitting batteries that eventually die and must be replaced, sometimes on hundreds of monitored circuits. Wiring in a powered meter usually requires an electrician and a shutdown, which is disruptive and expensive. The result is that most circuits go unmonitored simply because instrumenting them is too much effort. What is needed is a monitor that installs quickly, runs indefinitely without maintenance, and does not depend on an external power source.

What This Invention Does

The device monitors the current in a wire while drawing its own power from that wire’s magnetic field. It includes an inductive energy transfer medium, an energy storage device, a power management circuit, and a processing circuit. The inductive energy transfer medium induces an electromotive force from the fluctuating magnetic field around the monitored conductor, producing electrical energy that is kept in the energy storage device. The power management circuit controls both the storage and the release of that harvested energy, and the processing circuit measures the current in the monitored source based on the same fluctuating magnetic field. In effect the device treats the monitored wire as both its subject and its power source: energy harvesting keeps it running while it takes the measurement, so it can be clipped on non-invasively and left in place without wiring or batteries.

Key Features

• Self-powering. An inductive energy transfer medium harvests power from the monitored wire’s magnetic field.
• Energy storage. Harvested energy is stored in an energy storage device for steady operation.
• Power management. A dedicated circuit controls the storage and release of the harvested energy.
• Current measurement. A processing circuit measures the wire’s current from the fluctuating magnetic field.
• Non-invasive install. Because it needs no external power, the device can be attached without an electrician or shutdown.

Who Is Behind It

The applicant is Vutility, Inc., a company that develops self-powered, non-invasive submetering devices used to give buildings real-time visibility of their electricity use. The named inventors are Stephen K. Ellis and Kody S. Brown. This filing is a divisional application from an earlier related Australian application.

Why It Matters

As buildings and businesses work to cut energy costs and emissions, cheap, easy-to-install monitoring is the foundation for measuring and managing consumption. A sensor that powers itself and clips on without rewiring removes the biggest barriers to metering more circuits, feeding data to energy management and Internet of things systems. Protecting the device in Australia supports the rollout of granular energy monitoring across its commercial and industrial sites.

Related Concepts

• Electromagnetic induction – the principle that both powers the device and lets it read the current.
• Current clamp – the non-invasive current-sensing approach this device builds on.
• Energy harvesting – the self-powering strategy at the core of the invention.
• Electricity meter – the metering function the device performs.
• Internet of things – the connected systems that consume the monitoring data.

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AU 2026202023 was published in the Australian Official Journal of Patents on 2 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.