Earlier quoted context omitted.
This usecase is more about running it as a homeserver, where i guess that limitation is not that important. Of course there are a lot of usecases where the Pi is the better choice.
In my case I run my RPi2 as my home server, but off-grid from my non-grid-tie solar PV section, which is a nominal 12V, so a single part (switching 7805 2A, well plus cap) gets my power sorted nicely...
Here's mine:
thisisthebus.com