I'll describe a design for a bookcase:
It would be this large machine like device with lots of gears and mechanical arms and so forth. You select which book you want and pull a lever and the gears start turning and the mechanical arms move and it makes clanking and hissing noises. Steam shoots from the top of it and it vibrates and shakes. And after a few minutes of this, the book you selected appears in a tray at the bottom of the machine. Then when you're done, you put the book back in the tray, pull another lever, and the machine clanks and whines and puts the book back whee it was.
This bookcase would be powered by 27 AA batteries. One set of batteries would be good for 5 uses, and the whole thing would be 18 feet tall and weigh 2.7 tons. And it would be able to hokd a maximum of 5 books.
And still it would be more efficent then that bookcase shown in the pic.