Posters

Abstract

Wind generation is one of the main drivers to decarbonize power grids. As a renewable source of energy, it can produce reliable electricity with very low operational carbon emissions. While many electrical systems move towards reducing its operational emissions (i.e., losses), the focus change to so-called Scope 3 emissions, which are the equivalent GHG emitted to build equipment for windmills. Due to its usage of electrical steel and conductors, transformers are important contributors GHG emissions. Dry-type transformers were the first choice for windmills due to its enhanced safety performance, flexible design and low maintenance. Even though dry-type transformer maintenance need is still lower than the liquid filled transformers, as cooling the transformers efficiently is typically done by blowing atmospheric air into the transformer room, it makes the transformer exposed to contaminants such as moisture and salt which may impact the maintenance conditions. Furthermore, the continuous increase in power ratings of the windmills makes conventional dry-type technology often too heavy or too large and makes them almost impossible to fit into the available footprint in the nacelles and in towers. Worth to note that Scope 3 emissions of those equipment can also be of concerning. An available solution for those higher ratings is Hitachi Energy's dry-type transformers with CompactCool technology, which are liquid cooled dry-type transformers that applies a liquid coolant inside the coils to extract losses from windings and circulate the liquid to an external heat-exchanger that then dissipates the heat either to the external ambient or to a water circuit supply. This study compares overall climate impacts of such solutions (conventional dry vs CompactCool) on operational and life-cycle carbon emissions, as well resources and materials, considering different scenarios of the electricity carbon emission factor. The applied methodology to compute life-cycle emissions is presented as per ISO 14040/44.