Five sensor technologies for value-driven grid data management

The necessary transformation of grids, in a context of a world’s transition to renewable energy and of a growing demand for decarbonized electricity, requires an infusion of digital intelligence.

In this context, sensors are essential. They are the ‘eyes and ears’ of the modern power grid, providing invaluable data critical to the reliability, efficiency, and adaptability of tomorrow’s grid data management.

Five sensor data technologies are transforming today’s power grids.

1. Smart meters for an effective energy measurement

Smart meters come in three variations, each with different features:

• Standard smart meters accurately measure electricity consumption and enable remote meter reading, eliminating the need for manual readings. They often support time-of-use pricing, allowing consumers to save money by using electricity during off-peak hours.
• Intermediate models add two-way communication between consumer and utility. They offer load profiling, providing detailed data for optimizing grid operations and load management. They may also support outage detection, helping utilities respond promptly to power interruptions. These meters may incorporate tamper detection mechanisms, alerting utilities of potential electrical energy theft, which can result in important non-technical losses to the operator.
• Advanced meters often support demand response programs, enabling utilities to control or adjust electricity demand remotely during peak times. As power quality sensors become the standard, it will help to identify voltage fluctuations and sags. Grid monitoring capabilities offer insights into the health and performance of the distribution grid, such as low voltage arcing or faults, allowing utilities to take proactive maintenance measures.

2. Single and multi-conductor current sensors

To meet ambitious net zero targets and avoid volatile and rising energy costs, grids must reduce unnecessary energy wastage.

Sarah Marie Jordaan, Assistant Professor of Energy, Resources, and Environment at Johns Hopkins University, says 500 million metric tons of carbon dioxide can be cut by improving global grid efficiencies. These savings represent more than one percent of the worldwide CO2 annual emissions. But as Scottish-Irish physicist William Thomson, better known as Lord Kelvin, wisely said, ‘If you cannot measure it, you cannot improve it.’

Solutions such as single and multi-conductor current sensors are a game changer for process and plant managers. They are field-proven solutions that can be installed directly around conductors and cable feeders to selectively and rapidly deploy audit sessions. They enable installation without operation interruption so as to build concrete energy-saving strategies leading to energy consumption reduction of up to 20 percent.

3. Energy harvesting: converting small amounts of energy from the environment

In remote or challenging-to-access locations, the deployment of sensors poses sustainability and operational expenditure challenges, primarily concerning battery management.

With the industry set to witness over 25 billion connected objects in the sector by 2025, energy harvesting emerges as a pivotal technology to facilitate the expansion of sustainable sensors and Internet of Things (IoT) solutions.

As a concept, energy harvesting involves capturing and converting small amounts of energy from the environment or nearby power sources, such as cables. The most prevalent energy harvesting method is photovoltaic, which transforms light into electrical energy. Cost-effective and customizable for indoor lighting applications, it is an ideal fit for IoT solutions.

Inductive technology is another popular choice for cable systems. It empowers devices to operate independently by harnessing energy from power cores or terminations. This approach offers sensor functionality without the need for maintenance, delivers environmental benefits, and extends the system’s lifespan.

Recent advancements in electronic devices, including processing units and low-power wireless technologies, enhance overall efficiency and thus establish the harvesting approach as a reliable power source.

4. Edge-to-cloud: a revolution in maintenance practices

Edge-to-cloud integration is continuously revolutionizing maintenance practices, making them smarter and more efficient, particularly in the context of power grids.

5. Fiber optics: minimizing power disruptions

Optical fiber can be applied for remote data acquisition or as distributed sensor applications where traditional techniques are impractical or costly to deploy.

The emergence of fiber optic sensing technology is providing grid operators with a more cost-effective and accurate way of acquiring data compared to punctual sensors.

Distributed fiber optic sensing is the ability to continuously measure activity throughout the power grid, helping operators to quickly pinpoint the exact location of potential or actual disruptions and thus minimize or even avoid costly power outages.

Sensitivity of fibers to temperature and mechanical strain offer a comprehensive approach to distributed sensor applications:

• Distributed Temperature Sensing (DTS) enables the early detection of abnormal events such as hotspots and thermal bottlenecks due to condition changes in the surrounding laying environment of the cable. When combined with real time temperature rating algorithm, DTS systems allow to assess the operational condition and circuit power rating, allowing safer operation of the cable to its real conditions.
• Distributed Acoustic Sensing (DAS) offers precise fault detection, localization and third-party interference detection both onshore (e.g., cable theft, digging, and drilling) and offshore (e.g., anchor drops and drags). Thus, providing efficient power cable condition monitoring by listening 24/7 to acoustic signatures.
• Distributed Strain Sensing (DSS) continuously measures strain and deformation along the cable’s length. It enables the assessment of cable structural health data, ensuring that cables are not subjected to excessive mechanical stress (bending, stretching, etc).

Nexans has been at the forefront of distributed fiber optic sensing measurement technology for high-voltage (HV) cables since the early 1990s, beginning with the installation of a Distributed Temperature Monitoring (DTS) system used for the Skagerrak 3 link between Norway and Denmark. Since then, these technologies have undergone continuous enhancements in length, precision, efficiency, and cost-effectiveness.

With the emergence of innovative new technologies, sensors play a vital role in shifting to smart electrical grids. Sensors provide invaluable data critical to the reliability, efficiency, and adaptability of tomorrow’s grid data management.