TransAlta Corporation is engaged in the production and sale of electric energy. The Company is focused on generating electricity in Canada, the United States and Western Australia through its diversified portfolio of facilities fuelled by coal, natural gas, diesel, hydro, wind and geothermal resources. The Company is organized into three business segments: Generation, Energy Trading and Corporate. The Generation segment is responsible for constructing, operating and maintaining the Company’s electricity generation, as well as the operation and maintenance of its related mining operations in Canada. The Energy Trading segment is responsible for the wholesale trading of electricity and other energy-related commodities and derivatives.