Mexico's Federal Electricity Commission "was determined to support Texas with electrical energy faced with the problems the state is suffering due to climatological conditions," a statement said.
An energy transfer of 280 megawatts began recently via the north Mexican border cities of Nuevo Laredo, Reynosa and Piedras Negras, it added.
Texas Governor Rick Perry said in a statement that power and emergency management experts were working with utility providers to ensure power was restored as quickly as possible.
"Until that happens, I urge businesses and residents to conserve electricity to minimize the impact of this event," Perry added.
An epic winter storm Wednesday buried more than a third of the United States in drifting snow, sleet and ice that brought air and road travel to a halt.
Snowstorms also paralyzed air transport, blocked operations in factories and caused schools to shut in the Mexican city of Ciudad Juarez, across the border from El Paso, Texas.
Ciudad Juarez mayor Hector Murgia said the temperatures of around minus 13 degrees centigrade 8.6 Fahrenheit were the lowest recorded in almost 50 years.