Grid Enhancing Technologies · Glossary

Grid enhancing technologies, or GETs for short, are technologies and operating practices that allow existing power grids to be used more intensively. They reduce congestion or steer power flows more precisely, without new lines having to be built immediately. The term comes mainly from the grid debate in the US. In Europe, people often speak of grid optimising technologies, and in Germany, in the context of grid planning, of grid optimisation (Netzoptimierung). There is no uniform, legally binding list. The core usually includes dynamic line rating, power flow control devices such as phase-shifting transformers or flexible AC transmission system (FACTS) components, and optimisation of the grid topology through targeted switching. Depending on the source, grid sensors, digital control technology, forecasts, advanced conductors or storage are also counted as grid assets.

These technologies are not based on a common technical principle. What they share is their function in the power grid: they increase the usable transmission capacity or the controllability of an existing grid. In most cases, the physical limit of a line is not permanently shifted. Instead, the actual load-carrying capacity is determined more precisely, power flows are distributed differently, or temporary congestion is eased by operational means.

Which grid limit is addressed

A power grid has no simple capacity limit like a pipe. Lines, transformers and switchgear are subject to several technical limits at the same time. An overhead line may only be heated up to a certain conductor temperature, because otherwise it sags too much and no longer maintains safety clearances to the ground or to structures. A grid section can also be limited by voltage maintenance, short-circuit currents, stability requirements or N-1 security. N-1 means that the grid must continue to run safely even if an important asset fails, such as a line or a transformer.

The effect therefore depends on the type of congestion. With dynamic line rating, the current thermal capacity of an overhead line is determined from weather data, sensor measurements and models, instead of using a fixed, conservatively set limit. Wind and low outside temperatures cool the conductors, so that they can carry more current. Strong solar radiation, calm winds and heat have the opposite effect. In German grid planning, the method is called weather-dependent overhead line operation or overhead line monitoring. It does not apply in this form to underground cables, because their cooling hardly depends on wind.

A phase-shifting transformer, in Germany also called a Querregeltransformator, changes the phase angle of the voltage between two grid nodes. This allows current to be redirected from an overloaded path to a less loaded one. Flexible AC transmission system components influence voltages, reactive power or line flows. In topology optimisation, the switching state of the grid is changed so that load flows are distributed more favourably. Battery storage at congestion points can locally absorb or release electricity and thus relieve an asset.

What matters here is usually the electrical power, measured in watts, kilowatts, megawatts or gigawatts. Grid congestion arises from the power at a specific point in time, not from the amount of energy transmitted annually. A line is not overloaded because it transports many kilowatt-hours per year. It is overloaded when, in a specific operating situation, too much current flows simultaneously through a limited asset.

Distinction from grid expansion, redispatch and flexibility

Grid enhancing technologies must be distinguished from classical grid expansion. Grid expansion creates new physical capacity, for example through new lines, more powerful transformers or additional substations. GETs use the existing infrastructure more precisely or make it easier to control. In Germany, this sequence is laid down in the NOVA principle of the grid development plans: grid optimisation before grid reinforcement before grid expansion. Optimisation there includes, among other things, topology measures, power flow control and overhead line monitoring. Reinforcement includes, for example, adding extra circuits or replacing conductors. Advanced conductors, which are partly counted among the GETs in the US, fall under grid reinforcement rather than optimisation according to this classification.

GETs are also not the same as redispatch. In redispatch, the grid operator intervenes in the operation of generation plants, storage facilities or large consumers in order to avoid congestion. GETs can reduce redispatch, because they ease congestion in the grid itself or determine the permissible load more precisely. But they can also be part of a better redispatch system, when sensors, forecasts and switching measures provide the basis for more targeted interventions.

There is a close but incomplete overlap with flexibility. Flexibility is the ability of generators, consumers or storage facilities to shift feed-in or consumption in time. GETs, by contrast, are primarily means on the grid side. Depending on its use, a battery storage system can serve as a source of flexibility, as a grid asset or as a market asset. How it is to be classified depends less on the technology than on mode of operation, remuneration and responsibility. The term smart grid is broader: it covers communication, automation, measurement and data-based coordination across all voltage levels. GETs form a subset of it, insofar as they specifically improve usable grid capacity, power flow or the handling of congestion.

Why these technologies are gaining importance

With the expansion of wind power and photovoltaics, with heat pumps, electric mobility and the electrification of industry, load flows in the grid are changing. Electricity is increasingly generated where there used to be hardly any power plants, and consumed where new electrical applications emerge. In windy hours, a lot can be fed in in the north, while large consumption centres lie further south. Photovoltaics can place heavy loads on distribution grids at midday, and in the evening other congestion occurs. Grid situations therefore fluctuate more strongly in space and time than in a system with a few large power plants close to consumers.

Physical grid expansion nevertheless remains necessary. Lines, substations and transformers cannot be fully replaced by software, sensors or control devices. New infrastructure, however, requires long planning and permitting times, and the costs of congestion management rise when renewable plants have to be curtailed and power plants ramped up elsewhere. GETs can then serve as an interim solution, as a complement or as a permanent operational improvement. One example from Germany is grid boosters: large battery storage systems that counteract at short notice after a disturbance (curative). This can enable higher utilisation of the transmission grid in normal operation. The transmission system operators take such concepts into account in the current grid development plan.

Economically, GETs pay off where a comparatively small investment in measurement, control or regulation avoids high redispatch costs, makes more renewable electricity usable or postpones expensive line construction. This benefit depends heavily on location. Dynamic line rating brings little if a congestion is not thermally caused but due to voltage or stability. A phase-shifting transformer only helps if there are alternative transmission paths with free capacity. A battery storage system at the wrong grid node can make sense on the market but contribute little to the specific congestion.

Legal classification (as of November 2026)

USA, interstate transmission under federal jurisdiction: The regulatory authority FERC issued Order No. 1920 on 13 May 2024, effective since 12 August 2024. It obliges grid planners to consider dynamic line rating, power flow control devices, advanced conductors and transmission switching as possible solutions in regional and long-term transmission planning. They are not required to deploy these technologies. Order No. 1920-A confirmed the rule in principle.
European Union: In the Action Plan for Grids of 28 November 2023 (COM(2023) 757), the Commission calls on the associations of transmission system operators (ENTSO-E) and distribution system operators (EU DSO Entity) to make smart grid and efficiency technologies more visible. Among those named are dynamic line rating, static synchronous compensators (STATCOM) and phase-shifting transformers. The Action Plan is a political communication and not directly binding law.
EU network tariff regulation: Under Article 18(2) of the Electricity Internal Market Regulation, amended in 2024 by Regulation (EU) 2024/1747, the methodologies for setting network tariffs are to provide short- and long-term incentives, among other things for optimisation solutions in the existing grid. The Commission explains this in a notice on network tariff design.
Germany, transmission grid: The NOVA principle is a planning principle of the grid development plans, which are reviewed by the Bundesnetzagentur. In the Grid Development Plan 2037/2045 (Version 2025), measures are also classified by NOVA types in accordance with § 3 NABEG. Distribution grids are subject to their own planning and regulatory requirements, which are not presented in detail here.

Typical misinterpretations

A common oversimplification is that GETs could replace grid expansion. This blurs the difference between better use and additional infrastructure. If a grid section is structurally and permanently overloaded, for example because generation and consumption are far apart or large new loads are being connected, better operational management is often not enough. Sensors show the actually available capacity more precisely, but they do not create arbitrary new transmission capacity. Planning analyses from the US also recommend evaluating GETs as a complement to new lines and not only as their substitute.

Another misunderstanding concerns security. Higher utilisation is only a gain if it stays within the limits of operational security. Grid operators do not plan with average values but with permissible states, including in the event of possible disturbances. A line with reserves in normal operation must still not be loaded more heavily if an overload would threaten after an outage. GETs can determine or distribute these reserves more precisely, but they do not lift the security requirements. The phrase "digital grid optimisation" can also be misleading. New technology must demonstrably work reliably, be integrated into control systems, fit the protection concepts and be operated with clear responsibilities. An algorithm that reduces a congestion in a model is not yet an approved asset in the real grid.

Institutional and economic classification

Whether GETs are deployed depends not only on whether the technology is available. Grid operators invest within a regulated framework. If regulation recognises capital investments more favourably than ongoing operating costs for software, data or external flexibility, an incentive arises to invest rather in physical assets. This possible distortion is one reason why EU law has, since 2024, explicitly included incentives for optimisation solutions in network tariff regulation.

There is also the separation of market and grid. Electricity markets optimise generation and consumption according to prices, but grid congestion occurs physically at specific locations. If market participants see no or only weak spatial price signals, their schedules can aggravate congestion. GETs help the grid operator deal with such situations, but they do not answer the question of how grid costs and locational signals are reflected institutionally. The use of storage as a grid asset is particularly demanding. The same storage facility could earn revenues on the market, for example through arbitrage or balancing energy. This raises questions of unbundling, market distortions, remuneration and responsibility. Only institutional integration decides whether a storage facility may be used in a grid-serving way and who bears the costs.

What the term makes visible

The term makes clear that grid capacity is not a fixed number. Usable capacity depends on weather, topology, operating state, security rules, forecast quality and controllability. Besides the question of how many kilometres of line are built, this also brings into focus the question of how existing grids are operated, monitored and integrated into market processes. Which measure makes sense at a particular location, however, is not answered by the term. For that, the cause of congestion, grid level, load flow, operational security, costs, regulatory recognition and alternatives must be examined. GETs are not a catch-all term for any digitalisation in the energy sector. What is meant are technologies that increase the usable transmission capacity or the controllability of grid operation, without concealing the physical and institutional limits of the power grid.

Sources

Order No. 1920: FERC Reshapes the Transmission Planning Landscape — Crowell & Moring LLP (Zusammenfassung der FERC-Order); 2024. Executive Summary; Abschnitte Alternative Transmission Technologies und Compliance
Grids, the missing link – An EU Action Plan for Grids, COM(2023) 757 final — Europäische Kommission (EUR-Lex); 2023-11-28. Action 7
Commission Notice on network tariff design (OJ C/2026/126) — Europäische Kommission (EUR-Lex, Amtsblatt C); 2026. Randnummer 18 mit Verweis auf Art. 18 Abs. 2 der Strombinnenmarktverordnung
Netzentwicklungsplan Strom 2037/2045 (Version 2023), 1. Entwurf, Kapitel 4 Netzanalysen — Deutsche Übertragungsnetzbetreiber (netzentwicklungsplan.de); unbekannt. Kapitel 4.1.2 Das NOVA-Prinzip, Abbildung 31
Netzentwicklungsplan Strom 2037/2045 (Version 2025), 2. Entwurf, Kapitel 6 — Deutsche Übertragungsnetzbetreiber (netzentwicklungsplan.de); 2026-03. Kapitel 6.1.2 Das NOVA-Prinzip der Netzentwicklung; Abbildung 70

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Edited by eCMS on 12.11.2026 05:05