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National Transmission System

The National Transmission System (NTS) is the high-pressure gas pipeline network in that safely transports over long distances from coastal entry terminals and facilities to regional networks, stations, large users, and interconnectors for export. Comprising approximately 5,000 miles of pipelines, 21 compressor stations equipped with more than 60 compressors, and over 500 above-ground installations, the NTS forms a critical backbone for the country's infrastructure, delivering up to three times the annual energy volume transported by the electricity grid. Owned by a comprising Macquarie Asset Management (60.09%), Investment Management Corporation (27.71%), and Australian Retirement Trust (12.20%) as of September 2024, and operated by National Gas Transmission—regulated by under the Revenue = Incentives + Innovation + Outputs (RIIO) framework—the system ensures reliable gas supply while maintaining safety standards and adapting to evolving energy needs. Established in the late following the discovery of reserves, the NTS has expanded to connect major production points in the and , supporting both domestic consumption and the transition toward lower-carbon alternatives like transmission and transport networks. Its operation involves real-time balancing of through system management, contributing to Great Britain's and economic stability.

History

Origins

Following , the faced significant energy challenges, with reconstruction efforts increasing demand for reliable and affordable fuels. The gas industry, nationalized under the Gas Act of 1948, relied heavily on town gas produced locally from , supplemented by imported oil-derived feedstocks such as to meet growing needs. By the 1950s, over 90% of gas supply came from coal-based processes, but scarcity of suitable coals and the post-war boom in oil refining led to greater dependence on imported oil, exposing the system to supply vulnerabilities and higher costs. The discovery of substantial natural gas reserves in the North Sea during the 1960s transformed these prospects. The first major find occurred on September 17, 1965, when BP's Sea Gem rig struck gas at the West Sole field, approximately 42 miles off the coast, confirming viable domestic resources after earlier explorations inspired by the 1959 Groningen field in the . This breakthrough prompted the government, through the Ministry of Power, to initiate feasibility studies assessing the potential for a nationwide shift to , including requirements. In 1965, the Gas Council published its report " for ," advocating for based on these studies, which highlighted the economic and technical advantages of replacing inefficient town gas production with a centralized supply. In response, the government endorsed the conversion in late 1965, marking a pivotal decision to transition the entire gas to and reduce reliance on local manufacturing and imports. The Gas Council, established in 1949 to coordinate the 12 regional gas boards, took the lead in planning a national high-pressure transmission network to distribute the new resource efficiently, evolving from the earlier National Methane Pipeline approved by the Ministry of Power in 1961. This network was designed to replace fragmented local production with a unified capable of handling high-volume flows from fields and initial LNG imports. In 1966, Gas Council Chairman Sir Henry Jones formally announced the full-scale project, initiating the Conversion Executive to oversee the transformation, which began with trials at in June of that year.

Construction of the Network

The construction of the core National Transmission System (NTS) pipeline infrastructure in the 1960s and 1970s was divided into separate feeder networks for and to transport from coastal terminals to inland distribution points. In , the primary feeder pipelines originated from the West Sole field via the Easington terminal on the Yorkshire coast, extending southward across the estuary to major demand centers such as and the . In , initial pipelines carried gas from southern to and urban areas like and via extensions such as the Leeds-Newcastle line, until the field terminal at St Fergus began supplying gas in 1977. Engineering efforts centered on durable high-pressure pipelines, typically 30 to 36 inches in , capable of operating at initial pressures up to 1,000 psi to efficiently move large volumes of methane-rich over long distances. By the end of the , the constructed spanned over 4,000 km, forming the backbone of the UK's high-pressure gas . A pivotal early project was Feeder No. 1 from the Easington terminal, which began in and became operational in July of that year, delivering gas from the West Sole field—the first North Sea discovery—across the to the East Midlands Gas Board works at Paull. Subsequent feeders, such as No. 3 in 1969, further linked Easington to , including the South London Ring. Building the network presented significant engineering challenges, particularly in where rugged terrain, including hilly moorlands and river crossings, required specialized trenching techniques and route alignments to avoid geotechnical instability. Environmental considerations were addressed through practices like separation and reinstatement to limit long-term land disruption, though formal assessments were less standardized than today. Skill shortages in pipeline maintenance led to reliance on sub-contracted labor, helping to accelerate progress amid the rapid national conversion to . The English feeder network achieved full operational status by 1970, enabling widespread gas supply from southern terminals like Easington and Bacton. The Scottish extensions, starting with gas reaching in spring 1970 via the Leeds-Newcastle pipeline, were completed by 1973, integrating the northern grid with the main NTS.

Expansion and Key Milestones

Following the initial construction phase in the 1960s and early 1970s, the National Transmission System (NTS) underwent substantial expansion to integrate growing supplies from gas fields, with key additions including the Theddlethorpe terminal in 1972 and the St. Fergus terminal in 1977, which facilitated connections from northern offshore production areas. These interconnections enhanced the network's capacity to handle increased volumes, particularly as domestic production ramped up to meet rising demand. By the mid-1980s, further extensions supported the integration of new fields, such as the gas field via the Barrow terminal in 1985, marking a significant step in linking Irish Sea resources to the mainland grid. A pivotal milestone was the completion in 1982 of the fourth major feeder from the St. Fergus terminal, a 40-inch line that boosted overall and supported the influx of gas. In the , the system saw upgrades to stations and segments, enabling sustained operations at pressures up to 94 barg to accommodate higher throughput amid growing industrial and power generation needs. The 1988 Piper Alpha disaster, while primarily an offshore incident, prompted widespread safety enhancements across the UK gas sector, including revised protocols for onshore integrity, risk assessments, and regulatory oversight through bodies like the . The network's growth reflected the economic scale of North Sea development, expanding from roughly 2,500 km in to over 7,000 km by , driven by the of feeder lines and regional spurs. This expansion was further influenced by the privatization of under the 1986 Gas Act, which introduced , incentivized efficiency gains, and spurred investments in modernization without disrupting core transmission reliability.

Development of Storage Facilities

The development of storage facilities for the UK's National Transmission System (NTS) initially focused on (LNG) imports to meet peak demand and provide supply flexibility during the 1960s and 1970s. The pioneering terminal in , constructed by the Gas Council, became operational in 1964 and received the world's first commercial LNG cargo from aboard the Methane Princess on October 20 of that year. This facility featured six double-skinned storage tanks, each with a capacity of 4,000 tonnes, totaling approximately 24,000 tonnes of LNG, along with equipment to vaporize the liquid for injection into the gas grid, enabling buffering against seasonal variations in consumption. The terminal's design emphasized safety and efficiency, marking a shift from manufactured town gas to imported resources. The heightened concerns over , prompting increased investment in storage to mitigate supply disruptions and support self-sufficiency efforts amid rising global prices. LNG imports via continued into the late 1970s, peaking at about 0.3 billion cubic meters annually, but the boom in gas production—starting with the West Sole field in 1965—reduced reliance on overseas supplies. By 1979, the Algerian contract expired, and the Canvey terminal was decommissioned and repurposed for (LPG) storage, reflecting the transition to abundant domestic that diminished the need for early LNG infrastructure. In the late and , attention shifted to underground using depleted fields and caverns to handle the NTS's growing volumes. The Rough field in the southern , initially developed for production starting in 1975, was converted into the UK's first major depletion-type storage facility by , with operations commencing in 1985. Connected to the Easington onshore terminal in —upgraded for bidirectional flow—this site provided working gas capacity of approximately 3.3 billion cubic meters, equivalent to about 70 days of average winter demand at the time, and played a key role in balancing seasonal fluctuations. Concurrently, high-pressure storage evolved with facilities like the Killingholme site in , which opened in 1985 using chalk caverns at around 180 meters depth for LPG but informed techniques for applications. By the , these developments had expanded total NTS-accessible storage capacity to over 4 billion cubic meters, driven by Rough's dominance and initial salt cavern projects, ensuring greater as the network integrated more offshore supplies. This growth aligned with market liberalization under the 1986 Gas Act, prioritizing flexible storage to support competitive trading while avoiding over-reliance on imports.

Infrastructure

Pipeline System

The National Transmission System (NTS) consists of approximately 7,600 kilometres of high-pressure pipelines that form the backbone of the UK's transportation . These pipelines are engineered to operate at a maximum of 94 and incorporate diameters ranging from 12 to 48 inches to efficiently move large volumes of gas. The network links more than 20 entry points, including aggregate system entry points (ASEPs), to over 300 offtakes, enabling distribution to local networks, power stations, and industrial users across . The pipelines adhere to rigorous design standards, primarily utilizing API 5L-grade for construction, which ensures durability and resistance to operational stresses in transporting . Corrosion is mitigated through external coatings combined with systems, which apply electrical currents to prevent electrochemical degradation of the . Route planning emphasizes safety and minimal environmental impact, with the majority of the network comprising buried onshore segments that avoid densely populated urban areas; limited sections connect coastal terminals to the main grid. Key components include major feeder mains originating from North Sea gas terminals, such as the extensive lines from the Bacton terminal in , which integrate imported and domestically sourced gas into the system. The network is organizationally divided into zones, broadly categorized as northern, eastern, and western regions to facilitate regional management and flow optimization, with seven operational zones covering and the North, North West, North East, , South West, , and South East. Safety is enhanced by features like automatic shut-off valves, strategically placed to isolate sections in the event of pressure anomalies or detected leaks, complying with Pipeline Safety Regulations. Maintenance protocols for the NTS pipelines emphasize proactive integrity management to ensure long-term reliability. operations, involving the insertion of pipeline inspection gauges (pigs) through dedicated trap facilities, are routinely conducted to clean internal surfaces, remove debris, and assess wall thickness without excavating the buried lines. systems, incorporating computational and fiber-optic sensing technologies, were progressively implemented across the network starting in the early to enable and rapid response.

Compressor Stations

Compressor stations are essential components of the National Transmission System (NTS), with National Gas operating 21 such facilities equipped with over 60 units across to maintain gas pressure and flow. These stations boost the pressure of to counteract losses due to in pipelines, ensuring efficient transportation over long distances at speeds up to 25 mph (40 km/h). Typically, they achieve compression ratios of around 2:1 per stage, powered primarily by gas turbines that drive centrifugal compressors, though some incorporate electric motors for enhanced flexibility. Key compressor stations include Chelmsford in Essex, which supports eastern network flows, and Alrewas in Staffordshire (West Midlands region), aiding central distribution; capacities vary, with examples like Hatton in Lincolnshire featuring three 25 MW gas turbine-driven units for a total station output of approximately 75 MW. These facilities typically range from 100 to 500 MW in aggregate power across units, enabling the NTS to handle peak demands up to several billion cubic meters annually. Technical specifications emphasize centrifugal compressors with variable speed drives (VSDs) on electric units for operational efficiency and load balancing, often integrated with high-voltage supplies. Environmental controls at NTS compressor stations focus on reducing emissions, particularly nitrogen oxides (NOx), through technologies like Dry Low Emissions (DLE) combustion systems and selective catalytic reduction (SCR). These measures comply with the Industrial Emissions Directive and Medium Combustion Plant Directive, limiting NOx to below 150 mg/Nm³ in many cases. Post-2000 upgrades have included electrification pilots, with nine electric-driven compressor units installed by 2018 providing nearly 200 MW of capacity to lower the carbon footprint by eliminating direct combustion emissions at those sites. Ongoing projects, such as at Hatton and Wormington, replace older gas turbine units with more efficient models or electric alternatives to further cut CO2 and NOx outputs.

Storage Sites

The storage infrastructure integrated with the UK's National Transmission System (NTS) primarily consists of three types: depleted gas fields, salt caverns, and (LNG) terminals, which collectively enable seasonal balancing of gas . Depleted field storage, the largest category, utilizes exhausted onshore or offshore gas reservoirs to hold large volumes over extended periods. The Rough field in the southern , operated by Centrica Storage Limited, exemplifies this type and accounts for approximately half of the UK's total operational storage capacity with a current working gas volume of 1.5 billion cubic meters as of 2025. When fully operational, Rough provided up to 3.3 billion cubic meters, representing about 70% of national capacity, but it was closed in 2017 due to uneconomic operations and partially reopened in 2022, with expansions completed by 2025 enhancing deliverability. Salt cavern facilities, formed by solution-mining in underground salt deposits, offer smaller-scale but higher-speed storage suitable for short-term flexibility. The Holford site in , operated by , has a working gas capacity of 240 million cubic meters and supports rapid injection and withdrawal to respond to daily fluctuations in NTS demand. LNG terminals, such as South Hook in , provide additional buffer storage through regasification of imported liquefied gas, with equivalent working capacity of approximately 465 million cubic meters of natural gas across its five tanks. These facilities connect directly to the NTS via pipelines, contributing to a total accessible storage of approximately 3.2 billion cubic meters across nine operational sites as of 2025. Operationally, these sites manage seasonal peaks by injecting gas during summer surplus and withdrawing during winter demand, with Rough capable of withdrawal rates up to 44 million cubic meters per day and injection up to 100 million cubic meters per day at full capacity to support NTS flow stability. Salt caverns like Holford enable even faster cycles, with withdrawal rates exceeding 20 million cubic meters per day for intra-day balancing. Safety and monitoring protocols are stringent, incorporating seismic surveys to detect ground movement or leaks, particularly in salt caverns prone to , and periodic integrity tests such as pressure buildup analyses to verify containment. These measures align with directives on gas supply security and geological storage standards, adapted post-Brexit under regulations enforced by the .

Operation

Gas Entry Processes

The National Transmission System (NTS) receives primarily through over 20 designated System Entry Points, which include onshore terminals, (LNG) import facilities, interconnectors, and storage sites across . Key examples include the in , which processes North Sea gas from eastern fields, and the St Fergus Gas Terminal in Aberdeenshire, handling supplies from northern and Scottish sources. These entry points serve as critical gateways, where gas from diverse origins—such as production platforms, LNG plants like South Hook in , and cross-border pipelines—is aggregated before injection into the high-pressure NTS network. At these beach-head facilities, incoming gas undergoes essential pre-entry processing to meet NTS standards, including to remove and prevent formation, as well as to achieve the required up to 70 and temperatures between 1°C and 38°C. typically employs glycol absorption or other methods to ensure the remains below -2°C, while stations at terminals like St Fergus utilize turbo-expanders and de-ethaniser trains for liquids separation and flow optimization. These processes ensure the gas is pipeline-ready, free from interfering materials such as solids or excessive liquids that could damage infrastructure. Shippers nominate gas volumes for entry through the Gemini System, a centralized platform managed by Xoserve that facilitates daily trade nominations and allocation based on metered quantities at each . Allocations are determined using the User Daily Quantity Invoiced (UDQI) and Delivery Proportion formulas, with actual flows reconciled against nominations to maintain system integrity; meters at entry points record daily quantities, enabling precise tracking and invoicing. This mechanism supports around 2.6 trillion cubic feet (74 billion cubic meters) of annual gas entry, as of 2024, balanced against offtakes to minimize imbalances. Quality assurance occurs pre-entry through mandatory sampling and analysis at each facility, verifying compliance with strict Gas Entry Conditions outlined in the Uniform Network Code, such as a maximum CO2 content of 2.5% molar, calorific value limits of 36-56 MJ/m³, and absence of contaminants like hydrogen sulfide or mercury. Sampling systems ensure representative gas composition, with continuous monitoring via ultrasonic or turbine meters; non-compliant or off-spec gas triggers emergency protocols, including temporary shut-in or blending services at select terminals like Bacton and St Fergus to adjust parameters before acceptance. National Gas Transmission oversees these checks to safeguard network safety and interoperability.

Transportation and Flow Management

The transportation and flow management of the National Transmission System (NTS) relies on precise zonal pressure management to facilitate gas movement across Great Britain's high-pressure pipeline network. The system is designed to operate at pressures up to 94 barg, with zonal controls ensuring minimum pressures typically above 20 barg to support reliable delivery to offtakes and prevent operational constraints. Real-time monitoring is achieved through systems operated from the National Control Centre, which track key parameters such as gas pressures, flow rates, and linepack levels to detect and respond to fluctuations dynamically. These systems enable the system operator to adjust flows proactively, with compressor stations providing brief pressure boosts where needed to maintain momentum across the 7,600 km network. Balancing is a responsibility of the system operator, National Gas, which acts as the residual balancer to match total gas inputs and outputs on a daily basis. Under the , shippers are incentivized to manage their portfolios through mechanisms like the On-the-Day (OCM) for trades and imbalance notifications, with unresolved discrepancies settled via cash-out prices derived from system actions. These prices can impose effective penalties during tight markets, as exceeding linepack limits—such as a change of 15 million cubic meters (mcm) or more—triggers financial adjustments up to £24,000 per day for the operator, encouraging overall system stability. Linepack, the volume of gas held in pipelines, serves as a natural buffer, typically maintained between 80 and 100 mcm to absorb short-term imbalances without compromising pressure integrity. Capacity trading supports flexible flow management, with auctions for interruptible capacity allowing shippers to access additional entry or exit points on a daily basis through the Daily Interruptible System Entry Capacity (DISEC) process. These auctions, held the day ahead, allocate limited firm-equivalent capacity during peak periods, enabling peak daily flows of up to approximately 416 million cubic meters across the network. In emergencies, such as the 2017/18 cold snap, linepack maintenance and demand-side response tools like Operating Margins gas are deployed to handle disruptions, simulating extreme demands and averting supply shortfalls through coordinated notices and potential Network Gas Supply Emergency declarations. This integrated approach ensures the NTS meets the 1-in-20 peak aggregate daily demand standard, providing resilience against weather-driven volatility.

Offtakes and Connections

The National Transmission System (NTS) features over 500 above-ground installations (AGIs) that serve as primary offtake points, enabling the exit of to downstream users. These offtakes include approximately 129 connections to the eight regional Gas Distribution Networks (GDNs) across , where gas pressure is typically reduced from the NTS's high-pressure levels (up to 94 barg) to around 7 barg for safe distribution to residential and commercial consumers. Additionally, the NTS provides direct connections to about 35 gas-fired power stations and various large industrial users, such as refineries and chemical plants, allowing these major consumers to receive gas at higher pressures without intermediary distribution. Connection standards at these offtakes are governed by the and involve specialized AGIs equipped with metering, pressure regulation, and safety systems to ensure accurate measurement and controlled flow. Metering at AGIs records gas volumes in energy terms (kWh or ), facilitating billing and balancing, while pressure reduction stations use regulators and slam-shut valves to prevent over-pressurization in downstream networks. Capacity for these offtakes is allocated through a competitive process where shippers book exit rights via auctions, with trading and balancing coordinated at the National Balancing Point (NBP), the UK's virtual gas trading hub. This system ensures efficient allocation, with GDNs required to book sufficient capacity annually to meet forecasted demand while maintaining system . Notable examples highlight the NTS's role in serving high-demand areas. In the London region, operated by the GDN, multiple offtakes supply a substantial portion of the 's gas needs, supporting approximately 20% of national demand through dense urban infrastructure and major industrial sites. Internationally, the NTS connects to the BBL Pipeline at Bacton, enabling bidirectional flows of up to 20 million cubic meters per day between the and the , linking the NBP to European markets like the TTF hub for import/export flexibility. These interconnections enhance supply security by allowing gas to be sourced from or exported to during periods of imbalance. Demand patterns at NTS offtakes exhibit significant daily and seasonal variation, profiled to match consumption peaks, with power generation accounting for around 40% of total offtake volumes in recent years due to its role in electricity production. Domestic and commercial heating via GDNs dominate winter peaks, comprising the majority of the remaining demand, while industrial uses provide more stable baseload flows. This profiling integrates with upstream flow management to maintain system integrity, ensuring offtakes do not exceed available capacity without coordinated balancing.

Ownership and Regulation

Historical Ownership Changes

The National Transmission System (NTS) was initially developed and owned by the Gas Council, a public body established in 1949 to coordinate the UK's gas industry, which oversaw the construction of the high-pressure pipeline network starting in the early 1960s to distribute . Under the Gas Act 1972, the Gas Council was abolished effective 31 December 1972, and its functions transferred to the newly formed state-owned Corporation (BGC) on 1 January 1973, which assumed full responsibility for the NTS as part of its nationalized operations until privatization. The BGC maintained public ownership of the NTS, integrating it into a monopoly structure for gas supply, transportation, and distribution across . Privatization occurred under the Gas Act 1986, which transformed the BGC into on 8 October 1986, transferring the NTS to private ownership while retaining its integrated role in the company's operations. held the NTS until 17 February 1997, when it demerged into two entities: for retail supply and for exploration, production, and infrastructure, with retaining ownership of the NTS through its Transco business unit responsible for transmission and storage. In 2000, BG Group (the successor to BG plc) demerged its UK regulated infrastructure businesses, including Transco, into the newly listed Lattice Group plc on 26 October 2000, as part of efforts to separate transmission from other activities. This separation was influenced by the Utilities Act 2000, which established the Gas and Electricity Markets Authority and mandated functional and legal unbundling of transmission networks to enhance competition in the gas sector. On 1 October 2002, National Grid Group plc acquired Lattice Group plc for approximately £6.6 billion, forming National Grid Transco plc and consolidating ownership of the NTS under a unified entity alongside the electricity transmission system. The company was renamed National Grid plc on 25 May 2005, continuing to operate the NTS as its core gas transmission asset.

Current Ownership Structure

The National Transmission System (NTS) is owned and operated by National Gas Transmission plc (NGT), a standalone company established in 2021 as part of the operational separation from to facilitate the divestment of its gas transmission assets. This separation created NGT as a distinct entity responsible for the NTS, marking a shift from integrated ownership under National Grid to a specialized transmission-focused structure. As of 2025, NGT is wholly owned by a consortium of infrastructure investors through its parent company, Luppiter Consortium Limited, following the completion of National Grid's divestment in September 2024. The consortium comprises Macquarie Asset Management with a 60.09% stake, British Columbia Investment Management Corporation (BCI) with 27.71%, and Australian Retirement Trust (ART) with 12.20%. This full private ownership structure reflects the culmination of phased sales initiated in 2021, with the initial 60% stake sold to the consortium for £2.2 billion in cash (implying an enterprise value of approximately £9.6 billion for NGT's assets, including the NTS pipelines valued around £10 billion), followed by an additional 20% completed in March 2024 and the final 20% in September 2024. NGT operates as the licensed Transmission Operator (TO) for the NTS under the Gas Act 1986, regulated by , with no direct public ownership since the privatization of plc in 1986. The company's assets, encompassing over 7,000 km of high-pressure pipelines, compressor stations, and related infrastructure, support the secure transportation of across .

Regulatory Framework

The regulatory framework for the National Transmission System (NTS) is primarily overseen by the Office of Gas and Electricity Markets (Ofgem), which acts as the economic regulator responsible for issuing licences, setting price controls, and promoting competition and consumer protection in the gas sector. Ofgem ensures that the NTS operator develops and maintains an efficient, coordinated, and economical transmission system capable of meeting current and future demands. Complementing this, the Health and Safety Executive (HSE) enforces safety regulations, including risk assessments and operational standards to prevent accidents and protect workers and the public. The Uniform Network Code (UNC) establishes the commercial rules and contractual arrangements between the system operator, shippers, and other network users, covering aspects such as capacity allocation, balancing, and dispute resolution. Licensing requirements for NTS operation are governed by the Gas Act 1986, as amended, which mandates that transmission owners (TOs) hold a specific licence from to own, operate, and develop the high-pressure gas pipeline network. This licence includes obligations to ensure system security, non-discrimination in access, and compliance with technical standards. The current regulatory regime operates under the RIIO-2 price control framework (Revenue = Incentives + Innovation + Outputs), effective from April 2021 to March 2026, which allows the licensee to recover efficient costs while providing incentives for investments in reliability, innovation, and environmental performance through a totex (total expenditure) model. Compliance with the framework involves annual reporting to on key performance indicators, including system reliability and availability, where the operator must demonstrate adherence to output measures such as minimising unplanned outages and maintaining network integrity. Additionally, carbon reduction mandates align with the 's net zero emissions target by 2050, with holding a statutory duty under the Energy Act 2023 to consider this objective in its regulatory decisions, including incentives for reducing from operations like venting and supporting the transition to low-carbon gases. For international aspects, cross-border flows through are regulated via specific interconnection agreements, such as those for the Interconnector (UK) pipeline, which incorporate retained EU-derived rules adapted post-Brexit under the UK-EU Trade and Cooperation Agreement to facilitate secure and non-discriminatory access.

Regional Aspects

Northern Ireland System

The Northern Ireland gas transmission system operates as a distinct network separate from the National Transmission System, comprising approximately 429 km of high-pressure pipelines that deliver primarily to industrial users, power stations, and distribution networks serving around 25% of the region's households (as of ). This system, which became operational in the mid-1990s following the completion of key interconnectors, is managed by multiple independent operators under the oversight of the Utility Regulator for , ensuring localized supply security without direct integration into the broader UK offshore gas fields. The core infrastructure includes the Scotland-Northern Ireland Pipeline (SNIP), a 24-inch diameter, 135 km interconnector constructed between 1994 and 1996 that runs from Twynholm in under the to in , landing at the Ballylumford —a major off-take point supplying significant capacity. Additional pipelines encompass the 112 km North West Pipeline (NWP) from to the Coolkeeragh , the 26 km Belfast Gas Transmission Pipeline (BGTP) serving the Greater area, and the 156 km cross-border South North Pipeline () linking Gormanston in the to Antrim. Ownership is divided among entities such as Premier Transmission Limited (PTL, under Mutual Energy Ltd.) for the SNIP and BGTP, and BGE for the NWP and , reflecting the system's fragmented yet interconnected structure designed for regional resilience. Gas supply to the system relies almost entirely on imports from via the SNIP, with no direct connections to production fields, resulting in a smaller-scale operation compared to the NTS and a maximum operating of 75 barg to accommodate lower throughput demands. This import-dependent model supports peak daily flows sufficient for local power generation and heating but limits overall capacity to around 10% of the GB system's scale, emphasizing efficient cross-border coordination for supply stability. Development of the Northern Ireland network traces back to planning efforts in the 1960s and 1970s for infrastructure, which were significantly delayed by the socio-political instability of from 1968 to 1998, postponing major construction until the advanced in the early 1990s. In the , expansions such as the Gas to the West and Gas to the East Down projects have extended the network by over 200 km of pipelines (including 78 km of ), integrating renewable gas sources like biomethane to support decarbonization goals and accommodate growing demand from variable . These initiatives aim to enable up to 100% renewable gas transport by 2050, enhancing the system's role in Northern Ireland's net-zero transition while maintaining supply to key sites like Ballylumford.

Integration with Scotland and Wales

The National Transmission System (NTS) integrates through its northern feeder pipelines originating at the St Fergus Gas Terminal, a critical entry point on the northeast coast where gas from fields and Norwegian imports is processed and injected into the network. This terminal handles a substantial share of Great Britain's gas supply, with reports indicating it processes around 35% of the natural gas consumed in the , underscoring its role in securing national energy flows from upstream sources. Following in 1999, while the NTS remains a matter under jurisdiction with centralized ownership by National Gas, Scottish policy influences aspects of network planning and utilization, particularly through the Scottish Government's emphasis on strategies that prioritize decarbonization and renewable over fossil gas expansion. In , NTS integration centers on the region, where the LNG terminals—comprising South Hook and —serve as major hubs connected directly to the high-pressure . These facilities collectively manage up to 25% of the UK's LNG during peak winter periods, facilitating southward flows into the broader NTS and supporting industrial demand in the area. Devolved planning powers under the enable oversight of associated infrastructure developments, such as extensions and terminal expansions, through mechanisms like the Developments of National Significance framework, which streamlines consents for energy projects while aligning with regional environmental goals. The Isle of Grain LNG terminal in links indirectly via NTS interconnectors, enabling balanced distribution and reserve capacity sharing across the Wales- border. Inter-regional gas flows within the NTS between and are managed through a zoned charging structure, where entry and exit points are grouped into regions like North Scotland, , and the National Transmission System Area, resulting in differentiated transportation costs that reflect locational supply-demand dynamics and infrastructure constraints. Upgrades in the 2010s, including reinforcements to feeder pipelines, enhanced connectivity for industrial offtakes such as the in , improving reliability for cross-border transfers amid fluctuating production. Policy nuances, including the focus on accelerating net-zero transitions—such as repurposing pipelines for —have influenced investment decisions for Scottish NTS sections, while cross-border tariffs under the Uniform Network Code impose zone-specific fees to incentivize efficient flows between devolved regions.

Modern Developments

Hydrogen Blending and Decarbonization

The National Transmission System (NTS) is undergoing adaptations to incorporate as part of the 's transition to low-carbon energy, with blending trials demonstrating the feasibility of integrating into existing infrastructure. The H100 project, led by SGN and initiated in 2023, began supplying 100% —produced via powered by offshore wind—to up to 300 households in Buckhaven and Denbeath, , through a dedicated 8.4 km local transmission network in autumn 2025 for trials running until 2027. This initiative provides evidence on the operational viability of in high-pressure local pipes, supporting broader NTS decarbonization by testing end-use compatibility without relying on blending in that segment. Complementing this, the Brigg trial in 2025 achieved a UK first by injecting a 2% blend into the NTS, powering a gas-fired and validating safe transport and combustion at scale. A comprehensive national study published in July 2025 analyzed the impacts of blending into the NTS at levels up to 20% by volume, assessing effects on network operations, end-users, and . The study highlighted that such blends could propagate further into the network during low-demand periods like summer, while identifying needs for modifications in compressors and turbines at higher concentrations. Currently, content in the NTS is limited to 0.1% by volume under the Gas Safety (Management) Regulations , though consultations propose an initial cap of 2% to enable early deployment without extensive retrofits. Technical adaptations focus on material compatibility, with tests revealing risks of in pipelines, where atomic can reduce and increase fracture susceptibility under high pressure. These efforts align with the UK's Net Zero by 2050 target, positioning blending as a bridge to reduce while scaling low-carbon production. At St Fergus, the Acorn project integrates (CCS) to produce blue from natural gas reforming, with initial output planned from 2025 for blending into the NTS at up to 2%, capturing over 90% of CO2 for offshore storage. Investments exceeding £100 million have supported related R&D, including £29.9 million allocated to SGN for national transmission studies and broader government funding for electrolytic demonstration plants. Economic analyses indicate that full conversion of the NTS to 100% could offer a cost-effective decarbonization pathway for residential heating compared to alternatives like heat pumps, with repurposing costs estimated at lower than building new infrastructure.

Capacity Expansions and Challenges

The National Transmission System (NTS) has undergone targeted reinforcements to maintain its operational capacity amid shifting supply dynamics, with investments focused on compressor stations and import terminals. For instance, National Gas is installing three new compressor units at the St Fergus Terminal to enhance processing capabilities, with final cost submissions planned for 2025. Similarly, a new gas-powered compressor at Hatton Compressor Station became operational in May 2025, while a 15 MW gas turbine is scheduled for installation at Wormington Compressor Station by January 2030. These upgrades address compliance with emissions regulations such as the Industrial Emissions Directive (IED) and Medium Combustion Plant Directive (MCPD), which mandate modifications or decommissioning of older equipment by 2030. Overall, has proposed £2.5 billion in draft determinations for operating and maintaining the NTS during the RIIO-3 regulatory period from 2026/27 to 2030/31, ensuring resilience and secure supply to households and businesses. Looking ahead, capacity expansions are increasingly tied to the UK's net zero ambitions, including NTS infrastructure for low-carbon alternatives. Project Union, a flagship initiative, plans to develop a 2,500 km backbone by the mid-2030s, utilizing repurposed pipelines and new builds to connect production sites, industrial clusters, and storage facilities. In November 2025, approved £107 million for initial studies and development of Project Union components. Complementing this, the SCO2T Connect project aims to construct approximately 340 km of in Scotland's by 2035, enabling the capture and transport of up to 3.5 million tonnes of CO2 per annum to offshore storage at St Fergus. These efforts reflect a strategic shift, as the NTS demonstrates sufficient capability to meet Great Britain's gas needs safely through 2034, according to assessments by the National Energy System Operator (NESO). However, post-2035 uncertainties arise from evolving technologies, policies, and market conditions, prompting a review cycle for network reinforcements. Despite these advancements, the NTS faces significant challenges from declining domestic production and rising import dependence. UK Continental Shelf (UKCS) and Norwegian Continental Shelf (NCS) supplies are diminishing, with output projected to decline by approximately 7% annually, leading to over half of gas being imported, primarily via (LNG) terminals and interconnectors. This shift heightens the risk of constraints at key entry points, such as the terminal in , where increased LNG imports during low-demand periods (e.g., summer) could strain network flows, though safety and capacity obligations remain unaffected. Aging exacerbates maintenance needs, while a shrinking base—driven by and decarbonization of heating and power generation—complicates affordability, potentially leading to higher costs per user or asset stranding. Regulatory and transitional pressures further compound these issues, as the targets 95% clean power by 2030, reducing the NTS's role in and prompting a pivot to blending, biomethane, and carbon capture, utilization, and storage (CCUS). Balancing these changes requires enhanced measures, including potential government-backed mechanisms like cap-and-floor models, with consultations on network scheduled for autumn 2025 and transition planning for 2026. forecasts under various Future Energy Scenarios (FES) could reach up to 7,000 GWh/day by 2050, necessitating adaptive planning to avoid bottlenecks in a more volatile global market.

References

  1. [1]
    National Gas Transmission
    Every year, the National Transmission System (NTS) for gas quietly and efficiently delivers up to three times the energy transported by the electricity grid.
  2. [2]
    Gas transmission | Ofgem
    Nov 4, 2025 · The National Transmission System (NTS) is the network of pipes and pressure stations used to safely move gas at high pressure from its ...
  3. [3]
    [PDF] Lessons Learnt: Past Energy Transitions in the Gas Industry
    5.8 The National Gas Transmission System. Today's National Gas Transmission System (NGTS) grew out of the National Methane. Pipeline (NMP), which stretched ...
  4. [4]
    Running on fumes: how Britain squandered its gas wealth
    Feb 5, 2023 · But then, on 17 September 1965, 42 miles out in the North Sea, workers on a British Petroleum oil rig called Sea Gem made a surprising find: as ...
  5. [5]
    A history of natural gas in the UK - Office for Budget Responsibility
    In this box we summarised the historical events and changes that has led to the UK has become increasingly dependent on imported gas.Missing: post- WWII
  6. [6]
    History of the gas industry - National Gas
    The gas industry in the UK began in the 1790s, when Scotsman William Murdoch developed an experimental plant to manufacture gas from coal to light his home ...Missing: origins | Show results with:origins
  7. [7]
    None
    ### Summary of National Transmission System Pipeline Construction (1960s-1970s)
  8. [8]
    National Transmission System - Global Energy Monitor - GEM.wiki
    Dec 4, 2024 · National Transmission System is the United Kingdom's network of natural gas pipelines that supply both commercial and residential consumers.
  9. [9]
    [PDF] Gas Production from the UK Continental Shelf:
    Jul 1, 2019 · In 2017, gross production included 0.7 bcm of gas from the Rough field which was granted approval to cease storage operations in 2017 and began ...Missing: feeder | Show results with:feeder
  10. [10]
    The future of the UK gas network - ScienceDirect.com
    Construction of the NTS began in the 1960s and the majority of the current network was built over a 10-year period (Williams, 1981). Transmission pipes have an ...
  11. [11]
    None
    ### Summary of UK National Transmission System Evolution Post-1970s
  12. [12]
    Rough Gas Storage Facility, off the east coast of the UK - NS Energy
    Aug 24, 2023 · The field commenced gas production and processing in 1975, following the development of offshore facilities and Easington terminal.
  13. [13]
    Underground gas storage: An introduction and UK perspective
    For safety reasons a minimum pressure must be maintained within the National Transmission System ... 1981; Thoms & Gehle 2000; Crotogino et al. 2001; Cheung et al ...
  14. [14]
    [PDF] Rough gas storage undertakings review: Final decision - GOV.UK
    Apr 22, 2016 · This smaller installation was the original platform, completed in 1975 for gas withdrawal only. process gas from Centrica's York field.
  15. [15]
    None
    Summary of each segment:
  16. [16]
    Our network and assets | National Gas
    The National Transmission System consists of nearly 5,000 miles of high-pressure steel pipes and more than 500 above-ground installations. Gas is fed into the ...Missing: diameter offtakes
  17. [17]
    [PDF] System Flexibility on the NTS - Ofgem
    Dec 16, 2010 · National Grid Gas (NGG) is the owner and operator of the National Transmission. System (NTS). Gas shippers and gas distribution network (GDNs) ...
  18. [18]
    [PDF] Pipes, Fittings & Flanges Brochure - National Tube Stockholders
    Suggested Maximum Design Pressure based on S235 Min Yield*. 11,400. Temperature. Maximum Allowable Stress. LINEPIPE PRESSURE. TEMPERATURE RATINGS. PRESSURE ...
  19. [19]
    Pipelines and gas supply industry: FAQs - HSE
    Aug 7, 2023 · The Milford Haven pipeline will operate between 70 – 94 bar. The National Gas Transmission System (NTS) currently operates pipelines at up to 85 ...Missing: increase 1990s
  20. [20]
    Gas terminals - National Gas
    The Bacton Gas Terminal is a complex of five gas terminals across four sites, located on the North Sea coast of Norfolk. National Gas owns and operates one of ...Missing: zonal divisions West feeder
  21. [21]
    [PDF] Contents - National Gas
    1. PIG Trap assets which are used to enable inspection of buried pipelines on the NTS without full pipeline outage or excavation. These are located on NGT sites ...
  22. [22]
    Advances and challenges in oil and gas pipeline pigging technology
    Oct 8, 2025 · Magnetic flux leakage detection pigs utilize the magnetic flux leakage principle to detect surface and near-surface defects like cracks and ...Missing: NTS | Show results with:NTS
  23. [23]
    Pipeline Leak Detection & Testing: Methods & Best Practices - NiGen
    Oct 27, 2025 · Learn about modern pipeline leak detection and testing methods, including nitrogen testing, acoustic sensors, and computational monitoring ...Missing: UK NTS
  24. [24]
    Compressor stations - National Gas
    National Gas owns and operates more than 60 compressor units at 21 compressor stations around Great Britain.
  25. [25]
    [PDF] Annex A14.10 Compressor Train Engineering Justification Paper
    Compressor trains are made up of a centrifugal Compressor that pressurises the gas in the NTS. This may be powered by an Electric Drive or a Power Turbine.
  26. [26]
    https://www.nationalgas.com/sites/default/files/documents/Compressor%2520Train%2520Engineering%2520Justification%2520Paper%2520REDACTED_0.pdf
  27. [27]
    [PDF] Hatton IED Needs Case June 2019 - Ofgem
    Jun 10, 2019 · Hatton compressor station is currently equipped with three Rolls Royce RB211-24 25 MW gas turbine driven compressor units (Units A, B and C) ...
  28. [28]
    [PDF] Variable Envelope Compressor - National Gas
    The electric driven compressor comprises a variable speed electric motor directly coupled to the gas compressor. National Gas Transmission's fleet of gas.
  29. [29]
    [PDF] Peterborough and Huntingdon Compressor Stations January 2023
    This report seeks approval for the proposed option to comply with emissions legislation, ensure network resilience, and meet future supply/demand patterns. It ...
  30. [30]
    [PDF] Notice of variation and consolidation with introductory note - GOV.UK
    Jan 1, 2016 · The Hatton Compressor Station operates three gas turbine compression units. Units A, B and C comprise an industrial hot gas generator, power ...
  31. [31]
    Optimal operation of compressor units in gas networks to provide ...
    May 15, 2021 · Centrifugal compressors commonly used in high pressure gas transmission networks could be driven by gas turbines or electric motors. Including ...Missing: specifications | Show results with:specifications<|control11|><|separator|>
  32. [32]
    UK: gas storage capacity by site 2024| Statista
    ### Gas Storage Capacity in the UK (2024) - Summary
  33. [33]
    Rough responds to manage demand from early winter - Centrica
    Nov 29, 2024 · Centrica confirms that Rough reached a new record fill level on 5 November 2024 – the fullest the site has been since reopening in 2022. The ...
  34. [34]
    UK gas storage levels 'concerningly low' on weather, power demand
    Jan 10, 2025 · Rough storage levels decrease 20% from same time in 2024. UK sits at less than one week of gas demand in storage: Centrica.
  35. [35]
    Energy Storage | Uniper
    As an independent company, we offer access to 8 underground gas storage facilities in Germany, Austria and the UK with a total capacity of 80 TWh, which are ...Gas Storage Products · Gas Storage Technology · Hydrogen Storage · About us
  36. [36]
    Our Capacity - South Hook Gas
    It is one of Europe's largest LNG terminals, with the ability to regasify 15.6 million tonnes of LNG per annum and handle around 20% of UK gas demand. South ...
  37. [37]
    UK Gas Storage: Capacity, Sites and Security - Business Energy Deals
    The table below lists all nine UK gas storage facilities, showing their locations, owners, storage types, and how much gas each can hold in relation to national ...
  38. [38]
    Re-opening Rough: what are the prospects for gas storage this winter?
    Aug 8, 2022 · Even at a quarter of capacity, re-opening Rough would increase Britain's gas storage capacity by just over 1.5 times. ... UK gas storage capacity ...Missing: growth 1970s 1990s Hatton
  39. [39]
    [PDF] Rough gas storage undertakings review: Provisional decision
    Mar 4, 2016 · This represented 29.6% of total available withdrawal capacity. (485 GWh per day). 24 Injection and withdrawal represent maximum physical ...
  40. [40]
    E.ON opens new UK gas storage site | Reuters
    Dec 20, 2011 · The facility is expected to open its full 160 mcm capacity with eight storage caverns by the end of next year. "Without question the Holford gas ...
  41. [41]
    Regulation (EU) 2017/1938 of the European Parliament and of the ...
    This Regulation establishes provisions aiming to safeguard the security of gas supply in [F1the United Kingdom] by ensuring the proper and continuous ...
  42. [42]
    LNG terminals - Consent and operational issues - HSE
    Jul 29, 2025 · This document describes the legal framework and the role HSE has in ensuring safety at Liquefied Natural Gas (LNG) terminals in the UK.
  43. [43]
    Capacity - National Gas
    Capacity is essentially 'space' in the pipeline. Shippers must rent pipeline space for the duration they wish to move gas through it.
  44. [44]
    How Britain's National Transmission System (NTS) works
    The National Transmission System (NTS) is the network of high-pressure gas pipelines in Britain. We explain what it is and how it works.
  45. [45]
    [PDF] Part A – Gas Entry Conditions in respect of the NTS System Entry Point
    (p). Pressure shall be that required to deliver gas into the System taking account of the back pressure as the same shall vary from time to time. The delivery ...Missing: length diameter
  46. [46]
    St. Fergus Gas Terminal - NSMP
    Gas is processed by JT valves and/or turbo expander. Liquids are handled by two de-ethaniser trains. The identical gas trains are designed for parallel ...Missing: NTS | Show results with:NTS
  47. [47]
    Natural-gas processing - Wikipedia
    In the UK the hydrocarbon dew point is defined as <-2 °C for entry into the NTS. The hydrocarbon dewpoint changes with the prevailing ambient ...
  48. [48]
    Gemini System - Xoserve
    The Gemini System is a suite of online applications for managing the transportation of gas through the National Transmission System (NTS) in Great Britain.What is the Gemini System? · Applying for access to the...
  49. [49]
    None
    ### Summary of Gas Entry Processes into the NTS
  50. [50]
    Gas Quality - National Gas
    National Gas monitors the quality of gas at entry points to the National Transmission System (NTS). As a gas transporter, we are required by the Health and ...Missing: pre- sampling
  51. [51]
    [PDF] Gas Ten Year Statement December 2023
    St Fergus terminal is an entry point into the UK in the North of Scotland. ... The National Transmission System (NTS) is a complex system of physical assets such.
  52. [52]
    ITI Group consult on Net Zero SCADA for UK transition to hydrogen ...
    Oct 7, 2024 · ITI Group are partnering with National Gas Transmission on a project which will support the National Transmission System (NTS) to transition to hydrogen gas.
  53. [53]
    Residual Balancing | National Gas
    The maximum amount National Gas can lose is £24,000 for a single day, which is the penalty for a linepack change of 15mcm or more. The incentive recognises the ...Missing: UNC | Show results with:UNC
  54. [54]
    NTS Linepack | National Gas
    The model contains a database of NTS pipeline diameters and lengths, updated as required to accommodate changes to the network. ... Specific gravity is determined ...Missing: offtakes | Show results with:offtakes
  55. [55]
    Entry capacity | National Gas
    This page provides an overview of entry capacity, including the different types of capacity that are available, the different types of auctions (and the ...
  56. [56]
    [PDF] National Preventive Action Plan: Gas - GOV.UK
    According to NGT's data explorer, the peak winter day demand for 2022/23 was 416 million cubic metres (mcm) on the 15th of December, an increase of 46 mcm ...
  57. [57]
    [PDF] Gas Transmission Winter Review and Consultation June 2024
    Jun 20, 2024 · Cold snap (2017/18). We have simulated demands from winter 2017/18 as representative of demand levels during an extreme cold snap as this ...
  58. [58]
    https://www.nationalgas.com/our-businesses/entry-capacity
  59. [59]
    About Us - National Gas
    National Gas Transmission owns and operates the gas National Transmission System (NTS) ... 129 gas distribution offtakes; 35 gas power stations; 15 gas ...Missing: GDNs | Show results with:GDNs
  60. [60]
    [PDF] Exit Capacity Planning Guidance 2025 Final Outcomes Report
    Oct 1, 2025 · Permanent reduction in Assured Pressures at Cowpen Bewley offtake was accepted, but Coldstream offtake was declined due to the concern with the ...
  61. [61]
    [PDF] RIIO GD2 Business Plan Appendix Transmission Integrity ... - SGN
    Dec 9, 2019 · Our Transmission system comprises the following: Offtakes. We have 30 offtakes (12 in Southern and 18 in Scotland) that accept gas into ...<|control11|><|separator|>
  62. [62]
    Exit capacity | National Gas
    Exit capacity gives shippers the right to take gas off the National Transmission System (NTS). Capacity is often also referred to as 'rights' or 'entitlements'.
  63. [63]
    [PDF] Exit Capacity Planning Guidance - Ofgem
    Mar 19, 2021 · In order for Gas Distribution Networks (“GDNs”) to offtake gas from the National. Transmission System (“NTS”), they need to book exit ...
  64. [64]
    Gas Distribution in the UK Industry Analysis, 2025 - IBISWorld
    The industry comprises eight Gas Distribution Networks (GDNs) across Great Britain, owned by four companies operating regional monopolies.
  65. [65]
    Our International Connections - National Gas
    It connects the NBP hub (in Bacton, UK) to the ZTP hub (in Zeebrugge), with access to the TTF (Netherlands), PEG (France markets and surrounding LNG Terminals ...
  66. [66]
    [PDF] Experts in Networks - National Grid
    In October 2000, Lattice was demerged from BG Group and comprised Transco, together with start-up telecommunications and non-regulated infrastructure services ...
  67. [67]
    [PDF] May 2002 Proposed merger of National Grid Group plc and Lattice ...
    May 1, 2002 · Lattice. 4.2. Lattice was formed in 2000 by the demerger of BG Group plc and is primarily involved in gas transportation. Lattice also has ...
  68. [68]
    Our history - National Gas
    The business was rebranded and the regulated operating company (which owns, manages and operates the gas National Transmission System) was renamed to National ...
  69. [69]
    Our company structure | National Gas
    National Gas and its group of companies (together the Group) is owned by a consortium of investors, comprising Macquarie Asset Management (60.09%), ...Missing: current | Show results with:current
  70. [70]
    Sale of majority interest in NGGT and Metering - National Grid
    Mar 27, 2022 · National Grid plc ('National Grid') today announces that it has agreed to sell a 60% equity interest in its UK gas transmission and metering business ('NGG') ...Missing: Council | Show results with:Council
  71. [71]
    National Grid Completes The Sale Of Its UK Gas Network
    Sep 27, 2024 · Macquarie, an Australian investment fund renowned for its management of energy infrastructures, becomes the sole owner of NGT.
  72. [72]
    [PDF] RIIO-3 Draft Determinations – National Gas Transmission - Ofgem
    Jul 1, 2025 · Residual Balancing system operator costs as pass-through. 4.62. In its RIIO-GT3 Business Plan, National Gas has provided an early forecast of.
  73. [73]
    Licences and licence conditions - Ofgem
    We issue the licences that companies need in order to work in the energy markets, and set the conditions they need to meet.
  74. [74]
    Midstream gas system: update to the market - GOV.UK
    Jun 30, 2025 · Great Britain's gas demand used to be met by gas manufactured from coal, known as 'town gas'. After the discovery of North Sea gas in 1965, 13 ...
  75. [75]
    [PDF] End-to-end balancing guide - National Grid
    Compressor fuel usage is the energy used to run compressors to manage pressures within the gas transmission system. This can either be gas or electricity ...
  76. [76]
    Gas Act 1986 - Legislation.gov.uk
    Part I Gas Supply Introductory Licensing of activities relating to gas The gas code Gas transmission and the operation of gas interconnectors: independence
  77. [77]
    How we are regulated | National Gas
    Our licence to participate in gas transmission activities is established under the Gas Act 1986, as amended (the Act). This requires us to develop, maintain ...
  78. [78]
    https://www.gov.uk/government/publications/midstream-gas-system-update-to-the-market/midstream-gas-system-update-to-the-market
  79. [79]
    [PDF] RIIO-2 Gas Transmission Annual Report: 2023-24 - Ofgem
    Annual Delivery Incentives: NGT is performing strongly against annual incentive targets. It has received £31.9m in incentive rewards in RIIO-2. NGT ownership: ...
  80. [80]
    Ofgem welcomes proposed legal mandate to prioritise the UK's ...
    Jun 7, 2023 · Ofgem has welcomed the Government's amendment to the Energy Bill giving the regulator a statutory net zero duty.
  81. [81]
    Energy Security Bill Factsheet: Ofgem net zero duty (added 6 June ...
    Jun 6, 2023 · This measure clarifies Ofgem 's role in supporting government to achieve the net zero targets in the Climate Change Act 2008.Missing: transmission | Show results with:transmission
  82. [82]
    Trading gas with the EU - GOV.UK
    Dec 31, 2020 · The UK government has concluded a Free Trade Agreement with the EU to come into effect following the transition period, ending 31 December 2020.Missing: IPA | Show results with:IPA
  83. [83]
    At a glance: natural gas pipeline transportation and storage in ...
    Feb 9, 2024 · A gas transporter owns and operates a pipeline system in the United Kingdom that conveys gas from one point of the pipeline system to another. A ...
  84. [84]
    Networks | Utility Regulator
    The SNIP is owned by Premier Transmission Limited which is part of the Mutual Energy Ltd. group of companies.
  85. [85]
    [PDF] Households off the gas-grid and prices for alternative fuels
    Oct 24, 2024 · Northern Ireland's 2021 Census found that around half (49.5%) of households ... Between the Census 2011 and Census 2022 the proportion using mains ...
  86. [86]
    25 years ago Northern Ireland's natural gas industry was born
    Sep 20, 2021 · Unheard of in 1996, Phoenix Natural Gas is now one of the most successful private company start-ups in Northern Ireland's history.
  87. [87]
    Scotland–North Ireland Pipeline (SNIP) - GEM.wiki
    Dec 4, 2024 · Scotland-Northern Ireland Pipeline (SNIP) is a 24-inch, 135 km long natural gas pipeline which runs from Twynholm, Scotland and Islandmagee in Northern Ireland.
  88. [88]
    Gas - Mutual Energy
    Apr 22, 2025 · Premier Transmission Limited is the owner and operator of the Scotland to Northern Ireland natural gas transmission pipeline. The 24-inch ...Missing: length | Show results with:length
  89. [89]
    [PDF] Northern Ireland gas capacity statement 2024-25 - Mutual Energy
    Sep 30, 2024 · 200 km of gas pipelines (78 km being transmission pipeline) was commissioned by 2019 (the Strabane connection commenced operation before then, ...
  90. [90]
    [PDF] Northern Ireland Gas Capacity Statement 2019/20 – 2028/29 | GMO NI
    sufficient capacity to facilitate the connection of an additional power station of nominal. 450MW generation capacity. The sensitivity analysis on various ...
  91. [91]
    Gas (Northern Ireland) (Hansard, 19 July 1985)
    Jul 19, 1985 · We commissioned a very detailed study from Deloitte, Haskins and Sells to help plan the natural gas network at that time. I have the report ...
  92. [92]
    [PDF] Northern - GMO NI
    3.7 The Belfast Gas Transmission Pipeline (BGTP) comprises a further 35km of. 600mm pipeline with a maximum operating pressure of 75barg and runs from.
  93. [93]
    [PDF] NI Gas Network Pathway to Net-Zero
    Today, the distribution pipeline network stretches over. 6,000 kms. The distribution network is supported by a large volume transmission network managed by ...<|control11|><|separator|>
  94. [94]
    [PDF] SGN-Aberdeen-Vision-Project_Final-Report_0520.pdf
    Nov 25, 2020 · The study has demonstrated that 2% hydrogen can be injected into the National Transmission System. (NTS) at St Fergus and its distribution ...<|control11|><|separator|>
  95. [95]
    Scotland's electricity and gas networks: vision to 2030 - gov.scot
    Mar 12, 2019 · They are owned by Transmission Owners ( TO 's). SSE Networks in the north of Scotland and SP Energy Networks in the south of Scotland. National ...
  96. [96]
    UK's Dragon LNG terminal offers capacity from September 2029
    May 16, 2024 · With over 300 cargoes received, Dragon LNG has handled up to 25 percent of the UK's winter LNG imports in recent years, it said.
  97. [97]
    [PDF] The Planning Series 17 – Consenting energy infrastructure
    In July 2022, the then First Minister, Mark Drakeford MS, announced the Welsh · Government would bring forward an infrastructure consenting bill to simplify the ...
  98. [98]
    [PDF] Gas Network Capability Needs Report
    Dec 1, 2024 · For Scotland and the North, South Wales, and South East, we assessed both entry and exit capacities. RIIO Zone. Entry RIIO Zone. NTS Area. Exit ...
  99. [99]
    [PDF] Gas Ten Year Statement 2016
    Nov 1, 2016 · improvements to the health of over 2,000 NTS assets. Within the ... NTS pipelines transport gas from terminals to NTS offtakes and are ...
  100. [100]
    Grangemouth Industrial - just transition plan: supporting a fair ...
    Jun 18, 2025 · Strategic Pipelines – major Crude Oil, Ethylene, and Natural Gas pipelines linked to the Grangemouth cluster, as well as planned hydrogen ...Missing: 2010s NTS
  101. [101]
    H100 Fife: A world-first green hydrogen project from SGN
    Our world-first demonstration will bring 100% green hydrogen gas to customers for the first time, providing evidence for future low-carbon policy decisions.Missing: System blending 2023-2025
  102. [102]
    Pioneering SGN trial confirms UK gas network's potential for low ...
    Sep 3, 2025 · We have successfully completed a pioneering project in Scotland, demonstrating that the UK's gas network can be repurposed to transport ...Missing: blending | Show results with:blending
  103. [103]
    Brigg Breakthrough: Hydrogen Blending Powers Up UK's Net Zero ...
    Oct 13, 2025 · Centrica and National Gas have successfully completed a landmark trial, marking the first time hydrogen has been blended into the National ...Missing: H100 Fife
  104. [104]
    Hydrogen blending into the high-pressure gas grid marks a UK first
    Oct 14, 2025 · The trial involved National Gas injecting a 2% blend of green hydrogen into the gas grid, before being blended with natural gas to generate ...Missing: 2023-2025 H100 Fife<|control11|><|separator|>
  105. [105]
    National Transmission System hydrogen blending: study - GOV.UK
    Jul 23, 2025 · The project sets out analysis on the potential impacts of hydrogen blending in the national transmission system (NTS) at blend percentages ...Missing: 2023-2025 H100 Fife
  106. [106]
    Hydrogen blending into the GB gas transmission network - GOV.UK
    Jul 23, 2025 · The focus of this consultation is on hydrogen blending into the existing GB gas transmission network, however responses are invited from all ...
  107. [107]
    [PDF] National Transmission System hydrogen blending: study - GOV.UK
    Jul 22, 2025 · This study examines the potential impacts of hydrogen blending in the National Transmission System (NTS) at up to 2%, 5%, and 20% blend ...
  108. [108]
    Hydrogen pipelines and embrittlement in gaseous environments
    Jun 1, 2025 · Steel pipelines are susceptible to hydrogen embrittlement (HE) in high-pressure hydrogen gas environments, potentially leading to pipeline failures.
  109. [109]
    Acorn: Project Details - The University of Edinburgh
    Jul 31, 2023 · The hydrogen will be blended with natural gas in the national transmission system at St Fergus; the CO2 will be stored as part of Acorn CCS.
  110. [110]
    [PDF] Acorn Hydrogen Project - Technip Energies
    The Acorn Hydrogen Project reforms North Sea natural gas into clean hydrogen, safely mitigating CO2 emissions through the Acorn CCS infrastructure. The produced ...
  111. [111]
    3. Reducing emissions across the economy - GOV.UK
    We will be providing up to £140m to establish the scheme, including up to £100m to award contracts of up to 250MW of electrolytic hydrogen production capacity ...
  112. [112]
    Conversion of the UK gas system to transport hydrogen
    Jun 18, 2013 · In the 1960s, large deposits of natural gas were discovered under the North Sea and the UK Gas Council decided to switch the entire country from ...Missing: Ministry | Show results with:Ministry
  113. [113]
    [PDF] Gas Ten Year Statement 2024
    Dec 6, 2024 · We analyse the required network capability of the National. Transmission System over the short, medium, and long term to address our drivers of ...
  114. [114]
    Ofgem approves initial £24 billion to operate and maintain critical ...
    Jul 1, 2025 · Ofgem has given the provisional green light to an initial £24bn investment programme to enhance energy security.
  115. [115]
    Our view of the National Transmission System's capability to meet ...
    Dec 6, 2024 · Our first independent view of the National Transmission System (NTS) and its capability to meet GB's current and future network requirements.