Oil Filled Power Transformer Market Size - By Technology, By Rating, By Application, Growth Forecast, 2025 - 2034

Oil Filled Power Transformer Market Size

The oil filled power transformer market was estimated at USD 14.1 billion in 2024. The market is expected to grow from USD 15.1 billion in 2025 to USD 25.1 billion in 2034, at a CAGR of 5.8%, as per the Global Market Insights Inc.

• The aging American transmission grid is fueling demand for oil-filled power transformers. In 2023, the U.S. Department of Energy funded nine projects on advanced power transformer technologies with USD 18 million under the FITT program. The projects target improved grid reliability and supply chain limitations by developing modular, scalable, and thermally efficient oil-filled power transformers for transmission-scale applications.
   
• Across Europe, advance investments in transmission grids are propelling the installation of oil-filled power transformers. The European Commission puts the cost of transmission grid upgrades at USD 555.5 billion through to 2040. Such upgrades demand power transformers that are strong enough to take high voltage and varying loads, particularly with Europe integrating offshore wind and other alternative sources of power into its transmission backbone.
   
• Electrification and industrial development in Southeast Asia are driving demand for oil-filled power transformers. Based on IRENA’s report, by 2030 electricity access in the region is likely to be 100%, with overall generation potential approximated at 3,664 TWh, or 25% of the world's renewable potential. Oil-filled power transformers are vital to extending high-voltage transmission networks to meet this increase in industrial and urban energy demand.
   
• Africa's drive to interconnect its grids and drive industrialization is promoting the demand for oil-filled power transformers. REN21 points out that African electricity demand is expanding at 4% per annum, with tremendous effort in motion to make the shift from access to energy-enabled production. Oil-filled power transformers are essential in developing robust transmission infrastructure supporting regional trade and industrial expansion.
   
• Japan is updating power transformer standards to enhance energy efficiency. New targets for oil-filled power transformers in buildings and factories have been established by the Ministry of Economy, Trade and Industry (METI) to achieve an 11.4% decrease in overall power loss by FY2026 from FY2019 levels. The standards encourage the use of high-efficiency oil-filled transformers in medium-voltage transmission systems.
   
• Brazilian oil-filled power transformer demand is driven by huge transmission investments. In April 2024, Brazil contracted USD 4.06 billion worth of 4,471 km of transmission lines and substations with 9,840 MVA transformation capacity. These undertakings necessitate high-capacity oil-filled power transformers to aid in interregional grid expansion as well as renewable integration.
   
• The trend worldwide toward renewable energy is also making oil-filled power transformers with improved thermal and overload characteristics more necessary. With increasing wind and solar installations, transmission systems have to accept variable inputs while keeping the system stable. Oil-filled power transformers, with better insulation and thermal characteristics, are being put on the ground more and more in renewable-dense transmission corridors to make the grid reliable.
  
   

Oil Filled Power Transformer Market Trends

• Utilities are using modular oil-filled power transformers increasingly to expand grid flexibility and scalability. The configurations enable simpler upgrades, less downtime, and greater adjustability to fluctuating load conditions. The U.S. Department of Energy collaborated with General Electric in 2024 to install the world's first flexible large power transformer (165kV, 60/80/100MVA) featuring adjustable impedance and multiple voltage ratings, paving the way for future modular transformer installations.
   
• Power transformers are being outfitted with advanced insulation systems to cope with higher thermal and electrical stress. The materials lower aging and improve reliability, particularly for high-voltage use. The Idaho National Laboratory, in partnership with the DOE, tested advanced insulation materials under simulated grid conditions to analyze their performance and durability, with the goal of expanding transformer lifespan and lowering the frequency of maintenance.
   
• In seismically active areas, oil-insulated power transformers are being designed with added seismic protection capabilities. These include vibration dampers, strengthened tank structures, and flexible bushings. The DOE and INL are in the process of designing transformer bushing isolators to protect large power transformers from seismic activity, maintaining grid stability and limiting infrastructure damage. This is especially applicable to nations such as Japan, Chile, and sections of the U.S. West Coast.
   
• Smart sensors and IoT-based diagnostics are being used more in oil-filled power transformers to track oil quality, temperature, and load conditions. This makes predictive maintenance possible, lowers failure threats, and maximizes asset performance. DOE and NETL created fiber-optic sensors for detecting acetylene in transformer oil, improving early fault detection and monitoring of transformer health. All this digitalization is enhancing operating efficiency in transmission networks.
   
• Governments are encouraging indigenous manufacturing of oil-filled power transformers to minimize import reliance and counter supply chain vulnerability. This is fueling investment in local facilities, talent development, and raw material procurement. In India, the government's "Make in India" programme has prompted the expansion of domestic capacity for transformer makers, while the U.S. DOE is facilitating local transformer manufacturing through strategic investment and procurement policies.
   
• With the growth of renewable energy schemes, oil-filled power transformers are being designed to meet variable loads and fluctuations in generation. Their overload capability and thermal stability render them well-suited for renewable-abundant transmission corridors. Oil-filled transformers are being utilized in Brazil within solar and wind regions to smooth out fluctuating inputs and provide voltage stability over long-distance transmission lines to facilitate Brazil's transition to clean energy.
   
• Manufacturers and utilities are working together to harmonize oil-filled power transformer designs, simplifying procurement and enhancing interoperability. The trend enables quicker deployment, simpler maintenance, and higher compatibility in various grid environments. Global organizations such as IEC and IEEE are revising transformer standards to accommodate changing grid requirements, such as digital integration, environmentally friendly oils, and modularity, to simplify global transformer supply chains.
   
• The DOE's May 2023 Advanced Transformers Workshop brought together stakeholders to discuss design shortfalls, procurement policies, and tech-to-market approaches for oil-filled power transformers. Modularity, intelligent monitoring, and supply chain resilience were topics of conversation. Collective action is propelling innovation and informing future transformer technologies that meet the objectives of grid modernization and energy transition plans.
   

Oil Filled Power Transformer Market Analysis

• Based on technology, the market include forced oil, water cooled, self cooled and others. The market was valued at USD 12.2 billion, USD 13.1 billion, and USD 14.1 billion in 2022, 2023 and 2024 respectively. The water cooled segment dominated over 32% share in 2024 and is expected to grow at a CAGR of 5.2% through 2034.
   
• Self-cooled oil-filled transformers are increasingly preferred in remote or inaccessible transmission locations due to their passive cooling mechanism. These units require minimal maintenance and no external cooling systems, making them ideal for isolated substations. Their simplicity and reliability reduce operational costs and downtime, especially in regions with limited technical support infrastructure.
   
• In developing countries, where grid loads are moderate and infrastructure budgets are constrained, self-cooled transformers offer a cost-effective solution. Their ability to operate efficiently without forced cooling systems makes them suitable for medium-voltage transmission corridors, supporting gradual grid expansion without complex auxiliary systems.
   
• Water-cooled oil-filled transformers are anticipated to reach the market value of USD 7.6 billion by 2034. These units are gaining traction in urban substations where space is limited. Their compact design and efficient heat dissipation allow for high-capacity operation in confined environments. This makes them ideal for underground or enclosed installations in cities with dense infrastructure and high energy demand.
   
• Industrial facilities with established water systems are increasingly adopting water-cooled oil-filled transformers. These transformers benefit from enhanced thermal management, supporting continuous high-load operations. Their integration into industrial grids ensures stable voltage regulation and reduces overheating risks in energy-intensive manufacturing zones.
   
• Forced oil-cooled power transformers market was valued at USD 3.5 billion in 2024 and is anticipated to grow at a CAGR of 6% between 2025 and 2034. These products are essential for high-voltage transmission corridors due to their superior thermal performance. Their active cooling systems enable safe operation under heavy loads and fluctuating demand. Utilities deploying ultra-high-voltage lines rely on these transformers to maintain grid stability and prevent thermal failures.
   
• Renewable energy corridors, especially those connecting wind and solar farms to the grid, require transformers that can handle variable loads. Forced oil-cooled transformers offer rapid heat dissipation and overload protection, making them ideal for managing intermittent power flows and ensuring consistent transmission performance.
   
• Transformers using eco-friendly oils like natural esters are gaining popularity due to environmental regulations and sustainability goals. These oils offer high flash points and biodegradability, reducing fire risks and environmental impact. Utilities are increasingly adopting such systems in sensitive ecological zones and urban areas.
   
• Hybrid oil-filled transformers combining forced oil and air or water cooling are emerging as versatile solutions for dynamic grid environments. These systems adapt to varying load conditions and ambient temperatures, offering enhanced efficiency and reliability. Their flexibility supports deployment in both urban and rural transmission networks.
   

• Based on application, the oil filled power transformer market is segmented into utility, commercial & industrial and residential. The utility oil filled power transformers  holds a market share of 54.3% in 2024 and is anticipated to reach over USD 12.9 billion by 2034. Rising demand for efficient and reliable transmission networks across the globe will proliferate the business landscape in the coming years.
   
• The rise in residential electrification, including electric heating and vehicle charging, is increasing load demand on local grids. Oil-filled power transformers are essential for stepping down high-voltage power safely and reliably. According to DOE, residential EV charging strategies could increase summer peak demand by ~50% and shift peak hours to 7 PM by 2045, requiring robust transformer support.
   
• Over 55% of in-service transformers in the U.S. are older than 33 years, many serving residential areas. As these units approach end-of-life, utilities are replacing them with modern oil-filled transformers that offer better thermal performance and reliability. This replacement cycle is accelerating due to increased residential electricity consumption and the need for grid resilience.
   
• New residential construction, especially in suburban and peri-urban areas, is driving demand for oil-filled transformers to support grid extensions. These transformers are deployed in substations and feeder lines to ensure voltage stability and load management. The DOE notes that new customer additions are a major driver of transformer demand growth through 2050.
   
• Commercial facilities like data centers are consuming increasing amounts of electricity. DOE reports that data centers used 4.4% of U.S. electricity in 2023 and are projected to consume 6.7–12% by 2028. Oil-filled power transformers are critical for managing high loads and ensuring uninterrupted power supply in these facilities, especially where redundancy and thermal stability are essential.
   
• Industrial facilities are adopting demand response strategies to manage peak loads and reduce energy costs. DOE’s Better Plants program encourages industries to reduce energy intensity by 25% over 10 years, often requiring transformer upgrades for load shedding and efficiency. Oil-filled transformers with smart monitoring and overload protection are key to supporting these initiatives.
   
• The DOE’s Industrial Technologies Office highlights electrification of industrial processes as a major trend, contributing to increased transformer demand5. Oil-filled power transformers are deployed in high-load manufacturing zones to support electrified heating, welding, and automation systems. Their ability to handle sustained high currents and thermal loads makes them indispensable in modern industrial grids.
   
• Utilities are upgrading aging transmission networks with high-capacity oil-filled power transformers. The DOE’s transformer study highlights that failure of a single large power transformer can disrupt service and cause collateral damage, emphasizing the need for reliable replacements. These transformers are central to utility efforts to enhance grid resilience and reduce outage risks.
   
• Utilities are increasingly integrating DERs like rooftop solar and battery storage into the grid. Oil-filled transformers are required to manage bidirectional power flows and voltage fluctuations. DOE’s Electricity Demand Growth Hub notes that DERs are reshaping grid dynamics, requiring flexible transformer solutions to maintain stability and reliability.
   
• Large-scale solar and wind projects are driving demand for oil-filled power transformers in utility transmission systems. These transformers step up voltage for long-distance transmission and stabilize variable inputs. DOE’s reports indicate that renewable generation is expected to overtake coal by 2026, necessitating transformer upgrades across utility networks.

• The U.S. oil filled power transformer market was at USD 1.6 billion, USD 1.7 billion and USD 1.8 billion in 2022, 2023 and 2024 respectively. In 2024, the nation accounted for 74% of the North American market share and is expected to experience significant growth in the coming years.
   
• Following almost two decades of flat growth, U.S. electricity usage is once again increasing, led by commercial and industrial markets. The EIA predicts that electricity usage will rise at a rate of 1.7% annually from 2026, with commercial and industrial segments expanding at 2.6% and 2.1%, respectively. This growth requires growth in transmission infrastructure, which in turn requires greater demand for oil-filled power transformers with high-load capacity and guaranteeing grid resilience in various applications.
   
• U.S. utilities are expanding high-voltage transmission lines to achieve system balancing and reliability. The expansion helps incorporate new generating capacity, particularly from solar and battery storage. Oil-filled power transformers play a crucial role in stepping up and down voltages in such systems, providing thermal stability and fault tolerance. Their use is vital in places like Texas, California, and the Midwest, where grid upgrades are focused to ensure growing demand.
   
• The electricity industry in Canada has made a substantial decrease in GHG emissions, falling from 130.1 Mt CO2e in 2000 to 72.4 Mt CO2e in 2022. This transition towards cleaner sources of generation is fueling the need for oil-filled power transformers that facilitate renewable integration and high-transmission efficiency. These transformers are being used along hydro, wind, and solar corridors to provide stable voltage and handle varying inputs.
   
• In the last few years, between, Canada's commercial sector became more energy efficient by 15%, with savings of 142.7 PJ and USD 3.4 billion in expenses. With increasing adoption of efficient systems by buildings, low-core-loss transformers and smart sensors are being deployed to facilitate optimized energy consumption. Oil-filled power transformers are used due to their ruggedness and capability to perform in sustained loads for major commercial enclaves.
   
• The EU's Ecodesign Regulation (EU 2019/1783) requires a minimum efficiency level for power transformers to reduce energy losses by 16 TWh per year, or 3.7 million tons of CO2. Such regulations are compelling utilities and industries to replace aging units with high-performance oil-filled transformers, lowering total lifecycle costs and enhancing the performance of member states' grids.
   
• The share of Europe's renewables was 34% of power generation in 2024, with growing negative price events from inflexible generation. Oil-filled power transformers with new thermal and overload features are being used in transmission grids to handle the variability. Their function in voltage stabilizing and flexible grid operation is essential for integrating renewables and ensuring market efficiency.
   
• Southeast Asian GDP has expanded at 4.7% CAGR over the years, further boosting  electrification across the region. This expansion is straining the existing transmission infrastructure, leading to installation of oil-filled power transformers in industrial areas and cities. The transformers facilitate high-voltage transmission and guarantee secure power supply for manufacturing, transport, and residential sectors.
   
• Malaysia's Generation Development Plan features integrated system planning for transmission and generation that captures future decentralization and decarbonization directions. Oil-filled power transformers are key to this approach, providing voltage regulation and load management across growing renewable corridors. Their application facilitates national energy security and sustainability targets.
   
• The Middle East in 2023 experienced a 16.6% growth in renewable capacity, led by solar and wind installations. Oil-filled power transformers are being deployed in utility-scale renewable parks to handle high-voltage transmission and balance variable generation. Their thermal robustness and overload protection make them well-suited for desert climates and large-scale grid integration.
   
• Regional nations are investing in grid infrastructure to decrease the reliance on fossil fuels and improve energy security. Oil-filled power transformers are being implemented in new interconnection and transmission corridor projects, enabling long-distance power transmission and regional energy trade. Reliability and scalability are critical in achieving national diversification of energy objectives.
   
• The mining industry in Africa is increasingly turning to hybrid solar-diesel microgrids as a means of minimizing dependency on unreliable national grids and expensive diesel. This development is creating the demand for oil-filled power transformers for the transmission of high voltage and the perpetuation of operational continuity. In 2023, the Tasiast gold mine in Mauritania commissioned a 34 MW solar PV facility with an 18 MW battery system, providing 20% of its power requirements and preventing 530,000 tonnes of CO2 emissions over its lifetime.
   
• Solar PV systems are being utilized by industrial facilities throughout Sub-Saharan Africa to save on energy expenses and enhance dependability. Oil-filled power transformers are needed to integrate such systems into local networks and balance fluctuating loads. In 2023, South African mining operators agreed to invest USD 3.8 billion in solar PV installations worth 3,900 MW, including ventures by Sibanye-Stillwater, Anglo American Platinum, and Harmony Gold, with completion by 2025.
   

Oil Filled Power Transformer Market Share

• The top 5 companies across the Oil filled power transformer industry include Siemens Energy, Hitachi Energy, GE Vernova, Mitsubishi Electric, and Hyosung Heavy Industries, collectively contributing around 45% of the market in 2024.
   
• Siemens Energy holds a significant share in the oil-filled power transformer market due to its extensive product portfolio and global manufacturing footprint. Its offerings include large power transformers up to 2000 MVA and 765 kV, HVDC converter transformers, and phase-shifting units tailored for grid flexibility and renewable integration. Siemens Energy’s transformers are engineered for resilience, digital monitoring, and sustainability, supporting decarbonization and grid modernization. Their investment in U.S. manufacturing further strengthens their position in North American markets.
   
• Hitachi Energy commands a strong position in the oil-filled power transformer market through its delivery of over 20,000 units totaling 2,600 GVA, including 800 kV UHVDC and 765 kV AC transformers. Their TXpert Enabled digital transformers and EconiQ eco-efficient models offer advanced asset monitoring and reduced environmental impact. With a unified TrafoStar design platform across global factories, Hitachi ensures consistent quality and scalability. Their recent USD 1.5 billion investment to expand global transformer production further reinforces their market leadership.
   

Oil Filled Power Transformer Market Companies

Major players operating in the Oil filled power transformer industry are:

• Bharat Heavy Electricals Limited (BHEL)
• Bharat Bijlee Limited
• Celme
• CG Power & Industrial Solutions
• Daelim Transformer
• Eaton
• Elsewedy Electric
• Fuji Electric
• GE Vernova
• Hitachi Energy
• Hyosung Heavy Industries
• Kirloskar Electric Company
• KPRS
• LS ELECTRIC
• Mitsubishi Electric
• Ormazabal
• Schneider Electric
• SGB SMIT
• Siemens Energy
• Toshiba Energy Systems & Solutions Corporation

• BHEL is a dominant player in India’s oil-filled power transformer market, with over 6,000 transformers and reactors commissioned globally, totaling more than 6,000,000 MVA. Its product range includes generator transformers up to 765 kV, auto transformers up to 1200 kV, and HVDC converter transformers up to ±800 kV. BHEL’s transformers are deployed in major transmission corridors and HVDC projects, including the Raigarh–Pugalur and North-East–Agra lines. Its manufacturing capacity of 30,000 MVA annually supports large-scale grid modernization and export demand.
   
• CG Power is among the top 10 transformer manufacturers globally, offering oil-filled power transformers from 160 kVA to 1500 MVA and up to 1200 kV. It is the first Indian company to supply coupling transformers for STATCOM and SVC applications, and 132 kV green transformers. CG’s transformers are widely used in power utilities, railways, and industrial sectors across 80+ countries. Its collaboration with DuPont for SLIM transformers using Nomex insulation has positioned it as a leader in wind farm installations and compact high-performance transformer solutions.
   
• Mitsubishi Electric is a global leader in oil-filled power transformers, known for its shell-type and core-type designs. It manufactures transformers up to 1,510 MVA, including 765 kV autotransformers and gas-insulated units for compact installations. Mitsubishi Electric’s transformers are deployed in nuclear, thermal, and HVDC transmission systems worldwide. Its U.S. subsidiary, MEPPI, is the only facility in the country capable of producing 765 kV transformers, reinforcing its strategic presence in North America. The company’s focus on high-efficiency and seismic-resilient designs supports its global competitiveness.
   
• Fuji Electric maintains a strong presence in the oil-filled transformer market through its focus on energy-efficient and environmentally friendly solutions. Its integrated report highlights a commitment to sustainability and innovation, with operations in 60+ countries and a global sales ratio of 88.1%. Fuji’s transformers are part of its broader energy systems portfolio, supporting industrial automation and grid modernization. The company’s emphasis on ESG and its mid-term strategy “Fuji 2035” aim to expand its transformer business in line with global decarbonization and electrification trends.
   

Oil Filled Power Transformer Market News

• Eaton announced a strategic investment of USD 340 million in February 2025 to establish a new manufacturing facility in Jonesville, South Carolina, focused on producing three-phase transformers. The plant, scheduled to commence operations in 2027, will generate 700 new jobs and mark Eaton’s eleventh location in the state. This expansion is part of Eaton’s broader initiative to meet rising demand from utilities, data centers, and industrial customers, supported by over USD 1 billion invested in North American manufacturing since 2023.
   
• GE Vernova unveiled a USD 600 million investment plan in January 2025 to upgrade its U.S. manufacturing footprint over two years, aimed at addressing global electricity demand. The initiative will create 1,500+ jobs across engineering and production. Key allocations include USD 300 million for gas turbine manufacturing and USD 160 million for expanding the Greenville, South Carolina facility, adding 650 jobs. Additional investments target Grid Solutions plants in Pennsylvania and Florida, and the Niskayuna, New York research center, reinforcing GE Vernova’s innovation and energy leadership.
   
• CG Power & Industrial Solutions Ltd. approved a USD 3.1 million investment in October 2024 to expand its power transformer manufacturing capacity from 35,000 MVA to 40,000 MVA. This follows a series of upgrades, including a USD 14.6 million investment in FY23 that increased capacity from 17,000 MVA to 25,000 MVA, and further expansion of the Malanpur “T3” unit to 35,000 MVA, set for commissioning by March 2025. The company also scaled its distribution transformer capacity in Bhopal from 6,900 MVA to 9,900 MVA, supporting domestic and export demand.
   
• Elsewedy Electric partnered with Electric Supply Co., Energy Vault, and Wellhead Electric in February 2024 to support a major energy storage project in Southern California. The company supplied 28 pad-mounted transformers rated at 2,600 KVA, delivered within 18 weeks despite global supply chain constraints. The project includes a 68.8 MW (275.2 MWh) battery storage system installed at the Stanton W Power Energy Reliability Center, enhancing grid flexibility and reliability while enabling cost-effective energy storage for California’s evolving power infrastructure.
   

The oil filled power transformer market research report includes in-depth coverage of the industry with estimates & forecast in terms of revenue (USD Million) and volume (Units) from 2021 to 2034, for the following segments:

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Market, By Technology

• Self-Cooled
• Water Cooled
• Forced Oil
• Others

Market, By Rating

• ≤ 100 MVA
• > 100 MVA to ≤ 500 MVA
• > 500 MVA to ≤ 800 MVA
• > 800 MVA

Market, By Application

• Residential
• Commercial & industrial
• Utility

The above information has been provided for the following regions and countries:

• North America
  • U.S.
  • Canada
  • Mexico
• Europe
  • Germany
  • France
  • Russia
  • UK
  • Italy
  • Spain
  • Netherlands
• Asia Pacific
  • China
  • Japan
  • South Korea
  • India
  • Australia
• Middle East & Africa
  • Saudi Arabia
  • UAE
  • Qatar
  • Egypt
  • South Africa
  • Nigeria
• Latin America
  • Brazil
  • Peru
  • Argentina