GIL System
Ankura's GIL (Gas-Insulated Transmission Line) is redefining the future of power transmission with its groundbreaking technological breakthroughs and exceptional performance, providing global customers with more efficient, safer, and more economical power transmission solutions.
Environmentally Friendly Insulating Gas — Perfluoroisobutyronitrile（C4）
Molecular Formula: C₄F₇N (abbreviated as C4)
CAS: 42532-60-5
Sulfur hexafluoride (SF₆), a high-voltage insulating gas, is one of the six major greenhouse gases globally. Its global warming potential (GWP) is 23,500 times that of CO₂, with an atmospheric lifetime of 3,200 years.
Currently, the annual global emissions of SF₆ equate to 125 million tons of CO₂, and emissions are still increasing at a rate of nearly 10% per year.
Perfluoroisobutyronitrile (C4) is an ideal substitute for SF₆, capable of reducing greenhouse gas emissions by 99%, and has been widely adopted worldwide.
Physical Properties
Appearance under standard conditions: Colorless liquid or gas
Boiling point: -4.7°C
Freezing point: -118°C
Saturated vapor pressure: 252 kPa
Density: 7.9 kg/m³
Water solubility: 0.27 ppmw
Chemical Properties
High chemical stability, resistant to decomposition or other chemical reactions.
Non-flammable, reducing fire risks even when exposed to open flames or high temperatures.
Electrical Properties
Insulation strength is 2.2 times that of SF₆, effectively preventing current leakage and ensuring the safe operation of electrical equipment.
Provides rapid and effective arc quenching, preventing damage caused by electric arcs.
Environmental Performance
Global Warming Potential (GWP) is only 10% of SF₆, with an Ozone Depletion Potential (ODP) of 0, making it an eco-friendly gas.
Its biological toxicity is comparable to ethanol, posing minimal harm to humans.
| Properties | Perfluoroisobutyronitrile | Sulfur Hexafluoride |
| Molecular Formula |
C4F7N |
SF6 |
| Molecular Weight |
195 |
146 |
| Flash Point (°C) | Non-flammable | Non-flammable |
| Boiling Point (°C) |
-4.7 |
-68.3 |
| Freezing Point (°C) |
-118 ℃ |
-50.7 |
| Saturated Vapor Pressure (kPa) |
252 |
2149 |
| Gas Density (kg/m³) |
7.9 |
5.9 |
| Dielectric Strength (kV) |
27.5 |
14.0 |
| Water Solubility (ppmw) |
0.27 |
40 |
| ODP (Ozone Depletion Potential) |
0 |
0 |
| GWP (Global Warming Potential) |
2210 |
23500 |
| Atmospheric Lifetime (years) |
35 |
3200 |
| Toxicity | Low toxicity (comparable to ethanol) | Low toxicity |
The actual transmission capacity is 3 to 5 times that of the cable, and the maximum transmission current can reach 8000A;
The line loss is only one third of that of the cable.
The charging power is only 1/5 of that of the cable.
The GIL line is composed of inert gas, epoxy, and metal materials. Compared to cables, it has no risk of combustion or explosion. Compared to overhead power transmission lines, it is not affected by extreme weather conditions such as typhoons, rain, snow, and lightning strikes. The GIL does not pose a threat to surrounding equipment, environment, and personnel, and can solve the operational risks of cables and overhead lines in petrochemical and forest-grassland areas.
Full voltage coverage from 10kV to 1000kV
Suitable for diverse installation methods, including overhead, ground-level, direct burial, shallow trench, bridge-attached, and tunnel deployments.
Ideal for applications in petrochemical industries, steel and non-ferrous metal plants, computing centers, new energy projects, and urban power transmission scenarios.
Service life of 60 years, at least twice that of cables and 1.5 times that of overhead lines.
Unlike cables, GIL requires no reactive power compensation, fire protection investment, or additional intelligent monitoring equipment.
Whole-life-cycle operation and maintenance costs are reduced to one-third of those for cables and merely one-fifth of those for overhead lines.
The factory standard configuration enables condition-based maintenance. It includes insulation medium condition monitoring (real-time tracking of the temperature/humidity/density of the insulation gas), deformation condition monitoring (displacement and angle sensors to ensure structural safety, and optical fiber disturbance fault location). The proprietary GIL operation data management system enables real-time comparison of data from similar operating conditions.
Hybrid gas low-carbon solution: 30% SF₆ + 70% N₂ (reduces emissions by 70%), and the environmentally friendly gas C₄F₇N has nearly zero emissions.
99% of the materials can be recycled.
| Name & Unit | Power Cables | GIL |
|---|---|---|
| Actual Current-Carrying Capacity | Approx. 1200A | High capacity, 3-5 times that of cables |
| Service Life | 30 years | Full life cycle exceeds 60 years |
| Installation Method | Complex installation requiring trench excavation and drilling | Simple layout methods (tunnel/overhead/ground) |
| Safety | Combustion/explosion risks; high failure probability | No combustion or explosion risks; no bypass loss |
| Operation & Maintenance | Difficult fault prediction; external damage risks | Simple maintenance compliant with condition-based requirements |
The product has undergone numerous tests and has high safety and reliability.
