Recently published results and evaluations of extensive tests on the Neptune drum roaster show that the energy efficiency of the drum roaster has been significantly improved compared to the previous model. With the Neptune 1500 type 1 (formerly R1500/1), energy consumption still ran at 110 mega joules per 100kg of green coffee (roasting degree of 120 Colorette scale graduations). The new findings emerged from thorough a test series carried out by Probat's R&D department.

Considering further price increases in raw materials, a reduced consumption of up to a fifth cuts energy costs considerably. The average 10% reduction in consumption achieved is an enormous savings potential.

Various factors therefore contribute to decreased energy consumption in comparison to other drum roasters. In particular, it is Probat's recirculation system that improves the energy efficiency via full recirculation across the whole roasting process. The system feeds most of the still warm roast exhaust air back into the burner. The burner then requires less energy to get the air back up to roast supply air temperature. A further factor is the optimised insulation of the whole roasting machine.

Using modern insulation materials, it minimizes the costly loss of roasting heat. Moreover, the tightness of the drum was improved to prevent the suction of cold ambient air into the drum. Lastly, the modern burner technology equipped with a firing manager avoids unnecessary energy input during roasting with the Neptune.

Initially only available as a Neptune 1500, Probat complemented the series in mid-2008 with the Neptune 3000.

The Neptune 3000 has the same features as the Neptune 1500. Various optional extensions allow for an individual adaptation to customer requirements. Ii particular, the "Dark Roast" option package as well as the "Reflex Automatic" control extension enhance the roaster's variability. The development of extraordinary roasting profiles as well as ensuring reproducible quality is therefore enhanced.