Description

A gas insulated switchgear (GIS), typically housed in a high voltage substation, is a critical component in the substations of the transmission network of utilities or in energy-intensive industrial units. In general, GIS structures are contained in a metal-sealed environment with sulfur hexafluoride gas (SF6) as the insulating medium. A GIS’s basic functions include:

• Protecting transmission circuits through interruption of short-circuit and overload fault currents
• Enabling isolation of circuits from power supplies; as the GIS equipment is able to enhance system availability

Sales for high-voltage switchgear have always been closely tied to infrastructure investment into high-voltage transmission systems to support expansion of power generation, such as from conventional as well as utility renewable resources. However, the demand lately has also been driven by the need to upgrade aging substation infrastructure, as well as from heavy industries and data centers. Several energy-intensive industrial applications such as data centers are increasingly procuring and operating their own substations and therefore are in need of high-voltage power equipment, including GIS. However, the high cost of HV GIS equipment is among the top challenges faced by the industry. Any increase in prices of these systems will subsequently impact the demand for new switchgear equipment. High volatilities in raw material prices and trade tariffs (especially with most OEMs having their manufacturing facilities outside the US) contribute the most to restraining market growth. Further, refurbishment of old transmission and distribution (T&D) assets provides a cost-effective alternative to purchasing new equipment outright as it helps to defer the need to purchase new equipment by 10-15 years. However, OEMs are beginning to offer full refurbishment services that capatilize on the current market demand, thereby strategically hedging their revenue losses from the sales of new products.

GIS have several advantages over their air insulated (AIS) counterparts. But a couple of crucial advantages that have resulted in GIS dominating the market for high voltage applications are the space required for its construction and low levels of O&M costs. With growing levels of industrialization and urbanization, the need for space is a critical element in designing its installation. A typical GIS installation may take up to 90% less space than what an air insulated switchgear (AIS) will require.

Innovative design in GIS development has not only resulted in compact modular constructions, but also in the use of less environmentally harmful insulating gases without compromising on performance. SF6-free insulating mediums in GIS will most likely account for a large share in the market beyond 2025 as global regulations to curb the impact of climate change will lead to further SF6 restrictions.