TransCanada Corporation (TransCanada) is a North American energy infrastructure company focused on natural gas pipelines, oil pipelines and energy. During the year ended December 31, 2011, natural gas pipelines accounted for approximately 49% of its revenues, oil pipelines had 9% of its revenues and energy accounted for approximately 42% of the Company�s revenues. Its segments include natural gas pipelines, oil pipelines and energy. TransCanada is engaged in development and operation of North American energy infrastructure, including natural gas and regulated gas storage facilities. Its Keystone is a crude oil pipeline system. The energy segment includes acquisition, development, construction, ownership and operation of electrical power generation plants, the purchase and marketing of electricity, the provision of electricity account services to energy and industrial customers, development, construction and ownership and operation of non-regulated natural gas storage in Alberta.