The 10-ton and 20-ton EP2 Series can handle low, partial and full chilling loads. In head-to-head tests against 10- and 20-ton chillers equipped with fixed-speed and digital scroll compressors, the company says, the portable chillers with variable-speed compressors provided energy savings of 20 to 50 percent in a range of realistic and low-load conditions. This option is available on both water-cooled and air-cooled models from the company. The 20-ton chiller combines a 10-ton variable-speed compressor with a 10-ton fixed speed compressor. Consequently, the energy savings compared to conventional single-speed chillers are not significant in the middle-load range, where either compressor would be running at full capacity (10 tons). All portable chillers with the variable-speed compressor option from this company also include a touchscreen controller with easy-to-use operational and diagnostic screens.