I am currently learning all about digesters. It is interesting to learn that no matter what size farm you operate they can function. The best units are one’s that are “cookie-cutter” packages for farms with over a 1,000 cows, but they can be done for smaller farms too.
From the information that I have read so far, they really aren’t that difficult to construct and build. I have not gotten into the cost for the retaining walls, but I did find out that you can build them with a flex-wall! That would save loads of money over the traditional concrete I have seen used.
I think it may even work for a small farm like us. I will be completing some calculations over the next week or so to determine if it is an option for an operation as small as we are. I will update with the news of my discoveries on the topic!