Tough to burn stuff: Is it consuming more heat than it's producing?

[theholycow]

I receive/have large quantities of newspaper, cardboard, etc. Of course, a little can be used to start a fire. One can go to lots of effort to make firelogs out of it. One can just bring it all to be recycled, as most people do.

However, if I put a rolled up newspaper or folded up non-corrugated carboard in my fire, I wonder...does it make more heat than it consumes? I know if I try to burn it alone it won't stay burning, most of it will be unburned. OTOH, if I have a decent fire going, it will burn to ashes (and lots of them!).

Does this mean it's consuming energy or is it still producing energy and just needs the constant fire or higher temperature around it to keep producing?