Core4 Systems, Inc announced the introduction of its next-generation computer room air-conditioning (CRAC), air-handling units (AHU), and chiller systems. Unlike systems that use airside economizing (ASE) solutions that use more energy, require additional consumable expenditures for filters, and do not provide consistent temperatures and humidity levels, Core4 systems deploy refrigerant side economizing (RSE) that can reduce refrigeration compressor energy by up to 100 percent. Since Core4 deploys RSE directly in the return air and is based on the outside wet-bulb temperature rather than dry bulb temperature relied upon by ASE, economizing hours are increased by as much as 50 percent, as compared to airside economizing and typical waterside economizing.