As part of the LIFE programme, a European funding instrument for initiatives to preserve the environment and limit global warming, GE’s Grid Solutions is launching the LifeGRID project to enable electricity transmission and distribution companies to reduce their CO₂ emissions.

In response to climate change, GE Grid Solutions is committed to reducing greenhouse gas emissions. We have created g³, a gas for high-voltage electricity grid equipment. The mass of gas contained in high-voltage equipment using g³ has a CO₂ equivalent 99% lower than SF₆.

LifeGRID contributes to reducing greenhouse gas emissions thanks to the development of new 420-kilovolt switchgear using g³ gas.

What are electricity substations and high-voltage switchgear?

To transfer electricity safely throughout the grid, from the power station to the end customer, electrical substations are used to transform the high voltage into medium and then low voltage, and vice versa. They are also used to secure and route flows of energy. High-voltage electricity substations act as interconnections in electricity transmission grids. Inside a substation, high-voltage circuit breakers are protective equipment used to switch the flow of current if there is a problem on the network. 420-kilovolt high-voltage circuit breakers are found, for example, in substations along long-distance electrical lines.

Example of a 420-kilovolt gas-insulated circuit breaker used in a high-voltage substation.

The goal of the LifeGRID project is to develop 420-kilovolt, 63-kiloamp switchgear that will operate using g³ technology rather than SF₆. g³ is a mixture of gases used, like SF₆,  for dielectric insulation and as arc quenching medium inside the switchgear. Using g³ reduces the climate impact of the gas in the switchgear by almost 100%. The development of the 420-kilovolt g³ gas-insulated circuit breaker demonstrates that the g³ technology can be applied to all the other power grid voltage levels in Europe, opening the way for significant reductions in greenhouse gas emissions. Once its design is completed, the g³ switchgear should be the first SF₆-free 420-kilovolt gas-insulated substation switchgear in the world.

Exemple de poste éléctrique de 420 kilovolts isolé au gaz.

To evaluate and compare the climate impact of greenhouse gas emissions, they need to be compared with CO₂ emissions on the basis of their calculated CO₂-equivalent value (CO₂e)

The LifeGRID circuit breaker will be installed in high-voltage substations containing other electrical equipment which will also be encapsulated in gas-insulated compartments (see above).
The 420-kilovolt substations contain on average 10 bays and 1 km of gas-insulated lines. They have an operating life of at least 40 years.
This is an estimate of the CO₂e emissions avoided by using a 420-kilovolt substation over 40 years:

Using g³ gas leads to a drastic reduction, of about 99%, in the equipment’s CO₂ emissions. But equally importantly, it retains the size of the initial SF₆ equipment, meaning that the carbon footprint of the equipment can be kept at its lowest level throughout its lifetime. This has already been demonstrated by environmental life cycle analyses (LCA) conducted on the existing range of g³ products.

The development of the 420-kilovolt g³ gas-insulated switchgear will demonstrate that this technology can be applied to all the other electrical grid voltage levels in Europe, opening the way for significant reductions in greenhouse gas emissions.
As new equipment is commissioned, more and more CO₂e emissions will be avoided.