|Better Farming Series 32. Biogas 2: Building a Better Biogas Unit (FAO Better Farming Series, 1986)|
|How to build a better small biogas unit|
27. Before you build your new biogas unit you should decide where to put it. Items 26 to 34 in Booklet No. 31 will tell you where.
28. However, do not put this unit underground. If the unit is underground you will not be able to shake it to break up the scum (see Items 109 to 1 13 in this booklet).