Simple explanation. The article does not advocate the raising of cattle for purposes of generating heat - it is simply utilizing waste that already exists. This WASTE is renewable in a manner of speaking i.e. it is the by-product of already occurring practices. Instead of sending the left-overs to a rendering facility for full homogenization, they are using the leftovers to make heat. Instead of a landfill feast for sea gulls, we can generate something useful instead of more trash. And considering that biomass that is put into the landfills, regardless of how biodegradable the material is, will sit for decades unchanged (See National Geographic's article some time back where they dug up a 15 year old clump of lettuce from a landfill that was in no significant way degraded).

The secondary benefit is that instead of the smell of burning coal down-wind from the plant, you have the smell of hamburgers :)

Here is something that I have set up for a friend of mine and his wife, who both have computers in their homes, and have huge drives that they barely use. Vembu makes a backup system that is pretty slick, but their "personal" version allows for peer backups. Mr Smith's laptop backs up to Mrs. Smiths, and vice versa, free.

While this does not solve your NAS problem, it DOES solve your backup problem, while you either architect a solid solution within your budget, or at least give yourself the opportunity to raise your budget.

Hope this helps.

Bob