I could get behind this idea. Open Compute has a 48 volt rack specification, negative 48V is common in telecom since forever, PoE standards use roughly 48V, and

I could get behind this idea. Open Compute has a 48 volt rack specification, negative 48V is common in telecom since forever, PoE standards use roughly 48V, and 48V is at the upper limit of what's often considered "safe" by various standards and many (but not all) regulatory bodies across the world. What hurts 48V adoption is typically component cost. In the past there was a large price jump between 12V and 48V-60V capable circuits, with a lot of competition and demand at 24V from industrial stuff but less at 48V. Part of the problem is the huge ratios of 10x-50x between the voltages and the idea that the semiconductor switching elements have to be able to handle the peak voltages encountered in the system. In order to realize a 48V system at minimum cost you kind of need a flyback style power converter, leaning on a transformer's winding ratio to help. Dealing with custom magnetics sucks and engineers have in the past related to me how much they try to avoid dealing with magnetics. The frequency you want to use is high and this makes the magnetics smaller but increases the stress on the switching element (MOSFETs). The power you get off a flyback-buck like this can be a little noisy if not postregulated so you might need clever tricks to regulate it better to reduce that in the first place. I have noticed that high powered PoE adoption and lithium battery pack demand (like for electric bikes etc) is driving some of the costs on these things down a bit.