Hi Peter, Thank you very much for your time taken for this very thorough reply, finally sorting out this issue which has bugged me for a while. It makes sense that the biogas volume would be at field conditions. The elevation and atmospheric pressure remain an issue though, but I guess the range of values could cover elevation/pressure as well. I suppose one could assume sea level and then adjust for higher elevations if required. M&E also refer to the methane formula based on BOD which is very specific in terms of temperature and pressure, but unfortunately BOD and COD information in and out of AD's is seldomly reported in SA.  One could convert from VS to BOD or COD but this all adds to the variability of the answer. Thanks again for your reply, much appreciated. Best wishes, Andre

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Hi Peter,

Thank you very much for your time taken for this very thorough reply, finally sorting out this issue which has bugged me for a while. It makes sense that the biogas volume would be at field conditions. The elevation and atmospheric pressure remain an issue though, but I guess the range of values could cover elevation/pressure as well. I suppose one could assume sea level and then adjust for higher elevations if required. M&E also refer to the methane formula based on BOD which is very specific in terms of temperature and pressure, but unfortunately BOD and COD information in and out of AD's is seldomly reported in SA.  One could convert from VS to BOD or COD but this all adds to the variability of the answer.

Thanks again for your reply, much appreciated.

Best wishes, Andre