A very popular answer to this question is to select screw technology for best energy efficiency at lower flows and centrifugal technology for the higher flow demands. To advise the customer on the best technology fit, we have to look at the customer's application. It all starts from our customer's need. For sure, the energy efficiency will play a role in the final selection, yet other parameters like the compressed air demand profile will have to be taken into account as well. Applications that show a fluctuating air demand will benefit more from the wide turndown capabilities of a variable speed driven oil-free screw, while centrifugal units typically would be a better fit on more steady flow demand patterns. In most cases, the optimum selection is a combination of the 2: An oil-free centrifugal unit taking care of the base load combined with a variable speed driven oil-free screw unit to handle the fluctuating top load. This combo, together with our heat-of-compression dryers, forms a winning team, unique in the compressed air industry, providing ourselves and our customers the guarantee for success.