Probably a good idea to audit and analyze all heat loads in the building in order to minimize the heat load into the workspace. Every piece of equipment needs to be analyzed with a critical view toward reducing the heat load to the workdspace. Also, providing local cooling to specific high heat load machines ( lube oil water coolers instead of air cooling, for example, or "passive solar" shielding of the south side of the building and window louvers/shades).
The overall efficiency of the chiller system can be improved by (a) using a multistage chiller ( b) use of a working fluid better suited for the local ambient temperatures and rquired chilled water temperatures (c) improving the heat rejection system ( cooling towers) . If natural gas is available, one can (d) use the natural gas to fire a microturbine which powers the chiller compressors, and the turbine exhaust heat can operate an auxiliary absorption chiller. For item (d) the energy efficiency is on the order of 85% of the combined cycle, whereas the purchase of utility electircal power is on the order of 25% energy eficiency, including losses in transmission and generation.
