Hydrostatic Fan Drives Advantages of the Rexroth Solution Here you can see the benefits of hydrostatic fan drives at a glance.   Environment Compliance with exhaust emission regulations (EURO 4/5/6, TIER4, US10, Stage IV ...) Optimum control quality of all temperatures Measuring and weighting of many operating parameters Reduction in noise emissions Costs Significant reduction in operating costs up to 5 percent Long lasting Rexroth components System efficiency more effective compared to other fan drive technologies Function Steplessly variable fan speed independent of combustion engine speed High fan power at low combustion engine speed Reversing and fan standstill option Flexible device arrangement Small- and space-saving components Splitting of the cooler package Energy Cooling on demand: Demand-based regulation of cooling power and, thus, reduced fuel consumption Additional fuel savings with fan standstill option