Digital Twins: Turning complexity into better decisions

Modern transmission and distribution electrical grids are the most complex machines ever built. They span continents and encompass numerous interconnecting components and subsystems—while intricately balancing energy demand and fluctuating supply.

Not only are today’s grids complex, they are mammoth in terms of components and their geographical size. There are over one billion operational smart meters worldwide and the cables and lines stretch across 80 million kilometers. In other words: ten roundtrips between earth and moon!

And this complexity is only expected to grow. According to a newly released IEA report—Electricity Grids and Secure Energy Transitions—to reach climate targets and ensure energy security, 80 million kilometers of power lines will have to be replaced or added by 2040.

As power grids increase in complexity and scope, grid operators are turning to digital twins. While digital twins have been applied for decades by an array of industries, they are increasingly being used to help grid operators make strategic planning decisions, optimize operational performance, and manage risks within the context of unprecedented complexity.

3 factors that made grids so complex

1. As the world transitions from fossil fuels to renewables, grids need a better equipment to handle the variability of energy sources from wind, solar and hydroelectric.
2. The growing threat of severe weather caused by climate change is putting an additional strain on antiquated electric infrastructures globally.
3. 40GW of rooftop solar panels have been installed worldwide in 2022. This massive, fuzzy, intermittent deployment of solar energy injected into the grid has brought major challenges in power quality and load forecast management.

To handle these growing challenges, power grid operators have turned to digitization to improve the operational management of networks. Smart meters and IoT sensors provide operators with valuable data; yet, they add an additional layer of complexity.

Digital twins: From grid knowledge to understanding

With this increasing complexity and the overwhelming flow of real-time data, digital twins are proving pivotal to the operation of smart grids. They are used in order to:

• Simulate ‘what-if’ scenarios to understand, for example, operational outcomes of varying decisions
• Manage and foresee maintenance needs
• Avoid or limit grid downtime
• Help operators present data-backed asset investment plans.

The power of digital twins is their capacity to virtually reproduce the multi-scale interactions and correlations between organizations, thus providing a more holistic view of the grid and avoiding decisions made in silos. This gives decision-makers of any given department, such as engineering, planning, and operations, the ability to stimulate the consequences of various decisions and their impact throughout the organization. As such, calculated decisions are made based on implications, expected outcomes, and trade-offs and not just on past knowledge and experience.

Digital twins are revolutionizing grid management, as demonstrated by the landmark initiative to build a digital twin of Europe’s electricity grid. One of the initiative’s key aims is fostering innovative technologies in the race to ensure the readiness of the electricity grid for the drastic increase of renewable energy and resiliency to future shocks (such as climate and cyber-attacks).

6 key areas where digital twins are revolutionary

There are six key areas where the deployment of IoT-connected instrumentation sensors together with digital twins are providing impactful benefits and value to grid operators.

Digital twins represent a significant paradigm shift in electrical grid management. They facilitate all aspects of the business and operational mission of grid operators. They are paving the way for more reliable, resilient, efficient, and sustainable power grids, thus enabling the industry to meet its ambitions to be at the forefront of the transition to clean and decarbonized energy.

As a key driver to move away from fossil fuels, which are a massive source of CO2 emissions, renewables are an essential part of the future of energy. In this context of race against time to combat climate change, a growing emphasis is put on decarbonization of electricity.

The transition to renewable energy on a large scale is reliant on energy storage technologies. Energy storage is an essential part of the transition to clean energy and the foundation upon which the decarbonization of today’s grids must be built. Due to the intermittent nature of renewable energy — mainly wind and solar — grid operators must rely on energy storage systems to balance supply and demand. This interdependence means that storage is integral to grid resilience and reliability.

It is projected that by 2030, global energy storage installations will reach a cumulative 411 gigawatts (GW), according to the latest forecast from research company BloombergNEF — an increase of 15 times the storage online in 2021.

Other significant factors driving energy storage growth are government policies aimed at curbing increasing energy prices, meeting peak demand, and energy independence. In 2022, the Inflation Reduction Act (IRA) bill was signed into law, representing the U.S.’s largest investment to fight climate change.

Energy storage challenges: the need for widespread grid-scale technologies

A major challenge facing the industry today is the need for widespread grid-scale storage technologies. Today, the most viable solution is pumped-storage hydropower, which generates electricity by pumping water into a reservoir and then releasing it to generate electricity at a different time. Unfortunately, this technology can only be applied in specific locations. As such, grid operators must resort to fossil fuel energy sources to meet peak demand periods.

However, in recent years, advancements in storage technologies are now providing new opportunities for the potential to meet energy fluctuations in energy demand without resorting to fossil fuels. Thus giving grid operators the ability to store excess renewable energy and, to some extent, help balance in real-time energy demand to meet peak periods.

Five renewable energy storage technologies ensuring a reliable power supply

Proper energy storage ensures a reliable power supply as the electricity grid becomes more dependent on variable renewable energy (VRE) sources. What often differentiates technologies are their storage capabilities, reactivity, scalability, and application requirements.

Thermal energy storage: a viable alternative for commercial buildings

The emergence of newer thermal energy storage (TES) technologies is making it a viable alternative in commercial buildings. TES systems can store heat or cold to be used later and are divided into three types: sensible heat, latent heat, and thermochemical. When installed in a building, a TSE solution allows the building itself to act as a thermal battery — storing renewable energy in tanks or vessels to be used when needed.

Superconducting magnetic energy storage: for an instant and efficient release of energy

Superconducting magnetic energy storage (SMES) stores energy in a magnetic field. Because it can release stored energy instantaneously, it is considered ideal for grid applications requiring fast reaction time. Due to its negligible energy losses, there is increasing interest in finding a way to use it in large-scale energy storage applications. A few prototypes are currently in service, mostly under investigation, and they are beginning to be identified as a possible cost-effective solution.

What is the future of energy storage?

New materials and the development and supply of storage batteries for surplus renewable energy are quickly evolving to meet maturing requirements. Newer power electronics can convert stored energy into electricity to provide low to zero-impact solutions.

Nexans contributes in several ways to the energy transition, of which electricity storage is a key element, starting with the supply of transmission and distribution grids for the collection of renewable energy—wind and solar—at the source. It is crucial to collect electricity where it is generated (e.g. offshore wind farms) at an acceptable cost. The integration of storage sites is based on the same connection capacity, whether on a high-power scale or more widely distributed over a region.

Integrating variable renewable energies into smart grids will require an ever-increasing ability to monitor real-time usage requirements alongside automated systems in order to balance demand and supply loads. Faced with the need for greater flexibility, Nexans has developed new services accordingly.

For electric mobility applications, which are highly dependent on the technical and economic performance of electricity storage, Nexans supplies proper cable connections and protections, as for charging stations of electric vehicles, through specific safety functionalities to ensure safe energy storage.

Nexans has also acquired worldwide expertise and leadership in electrical and fire safety, that can be extended to the new applications of storage, such as vehicle batteries as they are becoming increasingly crucial.

The Group has been innovating for decades with industrial cryogenic and superconducting systems, such as with the development of a cryogenic transfer system of liquefied natural gas and hydrogen. As liquid hydrogen is very likely to play a key role in storage, Nexans will continue to innovate with breakthrough technologies to design tomorrow’s electricity grid.

Progress in energy storage technologies is vital to the transition to clean energy and the decarbonization of electricity. In the future, large-scale energy storage technologies will evolve and thus provide smart grids with the ability to reach their full potential. Diversifying and strengthening the supply chain of the new equipment for a massive deployment is a major challenge, especially for critical raw materials in a tense geopolitical context. Innovating by recycling materials used in end-of-life products is already a key driver, for which Nexans has prepared and positioned itself particularly well

As intermittent renewable energy becomes a larger share of the world’s power, grid flexibility will become increasingly instrumental. According to the European Commission Joint Research Center, compared to today, grid flexibility requirements will more than double by 2030 and be seven times as large by 2050.

As clean energy transition advances, grid digitalization will be an enabler alongside flexibility management. In recent years, grid digitalization investments have progressively increased from 12% of total grid investment in 2016 to 20% in 2022, driven by system operators requiring digital solutions to improve the management of the grid with real-time monitoring and control of energy flows for transmission and distribution networks.

Grid modernization is imperative to accommodate the expected electrification growth. Moving away from fossil-fuel-based electricity means that today’s grid must be able to integrate large share of renewable energy resources and address associated technical challenges.

Virtual power plants: The big move for electric generation

A new generation of distributed electricity resources (DERs) is gaining momentum as a way to solve the increasing demand for clean, renewable energy.

Advances in battery storage, EV and solar technology, coupled with the desire of utilities to expand renewable power, mean Virtual Power Plants (VPP) are fast becoming a favored approach to meeting growing electricity demand and the need for more resilient power systems.

A VPP is both a technical and transactional platform connecting a vast number of diverse resources to deliver, in seconds, a megawatt-scale power response to an instruction, reducing complexity for grid operators. In addition to the technical aspects, it provides the transactional flow by remunerating each resource for its contribution to the final service receiving payment from the Transmission System Operator (TSO), Distribution Grid Operator (DSO) or power market upon the available opportunity. Revenue stacking is gaining importance in delivering value to the DERs owners.

Because a VPP can provide power by tapping into the Distributed Energy Resources (DERs)—building blocks of VPPs—it can quickly balance supply and demand, thus avoiding potential power outages and reducing energy costs to the end user. In recent years, VPPs have increasingly been implemented in residential and commercial buildings to attract new buyers and provide reliable, lower-cost electricity. Even consumers can join a VPP. As an example, last year, Tesla launched its new power utility provider service in Texas that lets Powerwall owners sell excess energy back to the grid.

DER: paradigm shift in energy distribution

The distribution grid is facing unprecedented transformation as the growth in DERs increases. This transformation will require new levels of grid management and monitoring. The Advanced Distribution Management System (ADMS) is an essential component of the modern control center. Instrumental will be the digitalization of power flow observability, fault detection isolation and restoration, network reconfiguration and outage management systems. The new challenge of the distribution grid will predominantly be at the low-voltage level, where a greater level of observability is needed and requires the flexibility from DERs. This is where the Distributed Energy Resources Management System (DERMS) complements the ADMS by enabling a grid aware DER flexibility orchestration down to low-voltage level.

Grid digitalization: a journey

To solve the lack of network observability, Nexans is collaborating with Sensewaves to create a computable grid topology for DSOs. Sensewaves’ Artificial Intelligence-based analytics software leverages smart meter data (or other sources) to enhance planning and asset reliability (particularly cable systems) for DSOs. This unique combination of data analytics and AI provides invaluable insights beyond operational management typically offered through the ADMS and DERMS platforms.

Grid modernization is imperative to adapt to the expected electrification growth. Moving away from fossil-fuel-based electricity means that today’s grid must be able to accommodate the interconnection of renewables. New technologies in distributing, transmitting, and managing clean energy will play an instrumental role in reducing carbon emissions.

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.