Viable investment is somewhere around $150K to start(that would be very minimal). Around here its about $5 for 20 p0unds of those Eco bricks retail , that works out to $612/ton. I do remember that the estimate is 1 pallet of eco bricks = apx 1 cord of good firewood btu wise- just do not remember the weight if a pallet at present for comparison costs . In theory the retail cost of the bricks should be about equal to a cord( here average is $250/ cord mixed hardwood- same as pellets, about $250-299/ton, to be a viable function)) They really haven't caught on and then you have a lot of stove mfg saying using those voids warranty. That doesn't due much for sales as a business model- stand alone function. I have heard of but never been able to get my hands on the Idaho Energy logs - not distributed in my area. I have used a bunch compressed block products for my own edification. My take at present is great for the ambiance,casual,weekend cabin burners. So it is a niche sales area and very cyclic .
I also looked into , rather in depth, a stand alone production system - for me the the logistics were killers on the idea. As an add on to an existing business to use what would otherwise be waste requiring expenditure to get rid of it can work out or at least break even on a 7 year depreciation schedule. If you can garner enough Govt. subsidies to offset the intial equipment acquisition and operational costs say for 2-3 years it might fly. Sourcing , transport of raw materials - storage of same, and then storage and distribution of finished product are the devil details that can and will eat you alive. The actual equipment cost/ run is trivial in comparison. I do not mean to be discouraging- rather present this quick over sight as a informational post for a start to a business model. Chris