A system and method of reducing consumption of electricity used to cool electronic computer data center, networking, and telecommunications equipment, and to reduce the incidence of thermal failure of electronic components, includes provision of one or more partitions to reduce the volume of the cooled environment supplying coldest possible cooled air from air conditioning systems to a chamber adjacent to the cooling air intake side of electronic components, preventing dilution of the supplied cooling airflow by warmer air from outside of the reduced volume environment, and controlling the delivery of cooling air flow through the reduced volume of the cooled environment.