Presentation · EN — 29-slide Siemens Energy product presentation (September 2025, classified Unrestricted) on the 8VM1 Blue GIS up to 72.5 kV — a compact gas-insulated switchgear combining vacuum interrupting technology with F-gas-free clean air insulation for on- and offshore wind turbine installations. The deck motivates the step from 33 kV to 66 kV in wind-farm grids, explains the vacuum interrupter and clean air technologies (GWP 0, zero SF6), presents the full technical data table (up to 72.5 kV, 1250 A, 31.5 kA, IAC A FLR 31.5 kA 1 s), walks through the switchgear layout with eight numbered components, current transformer and voltage detection system, cable termination compartments, low-voltage compartment, and the offshore-specific transportation, installation and packaging system (factory pre-fill, transition-piece installation, sealed alu-foil packaging for up to 12 months of storage), and closes with the global installed base as of September 2025: 2900+ units contracted, 1330+ in operation.
Growing power demand requires a new generation of wind power plants equipped with innovative technologies. One core aspect (slide 2): due to enlarged wind turbine power, there is a need to increase the voltage level from up to 33 kV to 66 kV in the wind farm grid to decrease the current and therefore the cable losses. This is where compact, environmentally friendly, high-voltage gas-insulated switchgear (GIS) can make an optimal contribution.
The outstanding technical performance and low lifecycle cost of vacuum circuit-breakers make this solution the preferred technology in medium-voltage grids up to 52 kV. Based on more than 40 years of experience producing vacuum interrupters and more than 6 million delivered units, Siemens Energy introduced this proven technology to high-voltage grids above 52 kV in 2010 (slide 3).
Vacuum is utilized for arc extinguishing, giving (slide 3): zero CO2 emissions; hermetical tightness to protect from decomposition products; high switching performance without degradation; and zero maintenance ('sealed for life').
Vacuum interrupting technology facilitates the implementation of clean air as insulating medium in GIS. Clean air is composed of 80 % nitrogen (N2) and 20 % oxygen (O2), cleaned and free of humidity, with a Global Warming Potential (GWP) of 0. Expensive purchasing, handling, and recycling costs of SF6 or other insulation gases do not apply (slide 4).
Slide 5 frames the regulatory context: the EU F-Gas Regulation no. 517/2014 (in effect January 1, 2015) brings reporting obligations, personnel training, labeling and handling requirements aimed at minimizing F-gas emissions, and there is also a movement in the USA and Korea to gradually ban SF6 based on available technology per voltage level. The clean air value proposition is summarized as 'zero' across four dimensions (slide 5): zero environmental impact (no SF6 or other F-gases, zero GHG emissions and GWP, long-lasting design > 40 years and circular materials); zero impact on health & safety (no toxic insulation gases or decomposition products); zero regulation & special handling (no reporting or accounting of gases, no gas disposal at end of life); and zero compromise on performance (voltages from 72.5 to 145 kV, highest short-circuit switching capability with zero degradation, full performance down to -60 °C, maintenance-free interrupter unit).
The 8VM1 Blue GIS is a compact GIS solution designed for on- and offshore wind turbine installations, built on a well-proven modular platform concept based on decades of manufacturing and operating experience, as implemented in Siemens Energy's new generation of HV GIS (slide 6).
Main features (slide 7, verbatim): world's leading environment-friendly and future-proof technology free of F-gases; innovative clean air insulation medium significantly reduces carbon footprint; proven vacuum interrupter technology; compact GIS solution designed for wind turbine installations; completely factory assembled, tested and shipped in single transport unit; safe and easy handling; high operational safety; and low operational costs throughout the entire life cycle. The slide shows the typical switchgear configuration in offshore wind turbine installations: one circuit-breaker feeder toward the HV transformer cable and two outgoing HV array cables, each interface equipped with a voltage detection system (VDS).
Technical data as printed on slide 8 ('other values on request'):
| Parameter | Value |
|---|---|
| Rated voltage | up to 72.5 kV |
| Rated frequency | 50/60 Hz |
| Rated short-duration power-frequency withstand voltage (1 min) | up to 140 kV |
| Rated lightning impulse withstand voltage (1.2/50 μs) | up to 325 kV |
| Rated continuous current | up to 1250 A |
| Rated short-circuit breaking current | up to 31.5 kA |
| Rated peak withstand current | up to 85 kA |
| Rated short-time withstand current (up to 1 s) | up to 31.5 kA |
| Internal arc classification of HV cable compartments | IAC A FLR 31.5 kA, 1 s (acc. IEC 62271-200) |
| Leakage rate per year and gas compartment (type-tested) | < 0.1 % |
| Drive mechanism of circuit-breaker | stored energy spring |
| Rated operating sequence | O-0.3 s-CO-3 min-CO |
| Interrupter technology | vacuum |
| Insulation medium | clean air |
| Weight of SF6 or other fluorinated green-house gases | 0 kg |
| Rated filling pressure | 0.56 MPa abs |
| GIS width (depending on GIS configuration) | up to 2935 mm |
| GIS height | depth (depending on GIS configuration) | 2430 mm | up to 1230 mm |
| GIS weight (depending on GIS configuration) | up to 2.6 t |
| Ambient temperature range | -30 °C up to +45 °C |
| Installation | Indoor |
| First major inspection | > 25 years |
| Expected lifetime | > 50 years |
| Standards | IEC / IEEE |
The switchgear layout (slide 9) identifies eight components on a labeled cutaway with matching single-line diagram: (1) integrated local control cubicle; (2) circuit-breaker with vacuum interrupter; (3) spring-stored-energy operating mechanism with circuit-breaker control unit; (4) disconnector and earthing switch (hand operated); (5) disconnector and earthing switch; (6) current transformer (ring-core type); (7) Voltage Detection System (VDS); (8) plug-in cable termination. The single-line diagram runs from the HV transformer cable through the -QA1 circuit-breaker to two HV array cable feeders (-QZ92/-QZ93 switches, -XB2/-XB3 terminations), each with VDS.
8VM1 offers typical configurations for wind turbine applications (slide 10), illustrated with two arrangement variants and their single-line diagrams, positioned at the base of the wind turbine tower.
Customer benefits (slide 11): proven platform components of the actual Siemens Energy portfolio — (1) CB drive; (2) disconnector/earthing switch drive, pin- and conductor system; (3) pressure relief system; (4) density monitoring — plus integration of all functions in one single gas compartment; one single unit that is factory assembled and routine tested including protection & control; and maintenance-free operation during the lifetime of the wind turbine generator.
The current transformer (CT) is of ring-core type design and located in the cable compartment; the voltage detector system (VDS) uses a capacitive tap-off integrated in the cast-resin outer cone bushing (slide 12).
Cable terminations (slide 13) use plug-in cable connectors acc. to EN 50 673 — connection type F5, in complete and independent metal-enclosed compartments. The transformer cable termination compartment offers room for three cable connectors (type F5) and three surge arresters; the array cable termination compartment offers space for up to six or nine cable connectors (type F5). The cable termination compartments fulfill the Internal Arc Classification IAC A FLR 31.5 kA 1 s (acc. to IEC 62271-200).
The low-voltage compartment (slide 14) measures 700 mm (W) x 550 mm (H) x 550 mm (D), with removable bus wires and plugged-in control cables, panel control via conventional control devices or digital bay controller, and customer-specific configuration including equipment for protection, control and signaling.
The offshore delivery flow (slide 15) runs from the factory in Berlin — completely factory assembled and tested, pre-filled at 0.5 bar, sealed & packed — to the dockyard, where the GIS is installed in the transition piece (TP) and filled up to 4.6 bar; the TP including the installed 8VM1 is then shipped to its final destination. At the offshore wind park the flow continues with installation of the transition piece, connection of array cables and tower installation, after which the GIS is unpacked and energized; the switchgear operates in indoor condition.
The packaging system meets offshore-wind-specific requirements (slide 16): suitable for land transport by truck, sea transport via container and sea transport in an offshore wind turbine transition piece (TP); handling via fork lifter and/or crane; protection against mechanical and environmental impacts during transportation and storage; additional sealed packaging suitable for all climate conditions up to 12 months; simple opening and closing/re-sealing so the inter-array HV cables can be installed on the GIS with low effort; suitability for a partly energized GIS with inter-array lines in service; in- and outdoor storage; ambient temperature min. -25 °C / max. +55 °C; humidity ≤ 100 %; and labels/information carriers.
Two basic configurations exist (slide 17): minimum protection via tarpaulin cover — suitable for land transport and when the GIS will be installed in the tower; and full protection via sealed special air-tight and moisture-repellent alu-foil packaging plus tarpaulin cover on top — suitable for land transport and when the GIS will be installed in the TP at the offshore site for up to 12 months. For sea transport via container, an additional wooden box suitable for high-cube containers is added on top of the full-protection configuration (slide 18). Handling points on the different packaging configurations support crane and fork-lifter handling (slide 19).
Inter-array HV cable installation shall be performed by trained staff only, following the dedicated manual; each inter-array HV cable compartment includes a dedicated repair/re-seal kit (slide 20). The sealed alu-foil packaging offers zippers at the needed areas for simple access to the installation areas of the switchgear, and technically needed cutting areas are reduced to a minimum and marked with red dotted lines on the alu-foil (slide 21).
As of September 2025, the global project reference count for the 8VM1 Blue GIS stands at 2900+ units contracted, thereof 1330+ in operation (slide 22, shown on a world map of deployment countries). The presentation's individual reference-project slides (slides 23-26) name customers and projects and are therefore omitted from this entry per catalog guardrail.
The closing summary (slide 27) condenses the deck into five essentials. Environmental-friendly: the 8VM1 uses clean air as insulation medium — a composition of 80% N2 and 20% O2, cleaned and free from humidity (technical air), with GWP 0; clean air is not and will not be part of the EU F-gas regulation. Experience: the 8VM1 is based on vacuum interrupter technology with more than 40 years of successful operational experience in medium-voltage and since 2010 in high-voltage, and offers well-known and proven design components of the Siemens Energy high-voltage GIS portfolio.
Robustness: the compact layout leads to high mechanical resistance regarding transport and operation in a wind turbine generator and an improved seismic resistance level 'high' acc. to IEC 62271-207. Installation and commissioning: the 8VM1 is completely factory assembled, routine tested and shipped in one single transport unit for maximized readiness to installation in a wind turbine generator. Highest quality and reliability: the 8VM1 is type tested acc. to relevant international standards and is the world's only 72.5 kV high-voltage GIS with cable compartments obtaining Internal Arc Classification IAC A FLR 31.5 kA, 1 s acc. to medium-voltage standard IEC 62271-200.
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