Hara Ra wrote:
> [Dan Clemmensen wrote:]
> >IMO by the time we have replicators, we can consider the biological model
> >for solar energy storage: plants store a lot of energy in a distributed
> >manner. I'm pretty sure that the energy density of biochemical storage
> >greatly exceeds the energy storage in a battery.
>
> You forget that a biological body oxidizes oxygen from the air. A fuel cell
> with a supply of fuel and oxidizer will have a higher energy density.
>
Probably true, and applicable for space-going applications. However, on
the ground, and from a systems perspective, there is no reason not to
treat the atmosphere as part of the storage system. In particular, from
a practical standpoint we're competing against gasoline-burning IC engines,
which also use biochemical energy storage and atmospheric oxygen.