if you're starting with a block of aluminum or a bin of powdered aluminum, then yeah, the tooling for machining the solid block would likely take less energy th

if you're starting with a block of aluminum or a bin of powdered aluminum, then yeah, the tooling for machining the solid block would likely take less energy than the laser used for sintering the powder. However if you take into account the energy necessary to cast the aluminum block in the first place, the laser may be more efficient. But, for all I know they take cast aluminum billets and some how shred/powderize instead of making the powder as it is refined.