The variation of temperatures ranges from 52 ºC to 57 ºC while keeping
other parameters constant such as the total solid concentration, organic load and pH. The highest biogas yield
from industrial wastes and energy plants was found at 52 ºC with average yield of 674.4 l·kg-1·VS-1 and energy
value of 14.2 MJ·kg-1·VS-1. By rising temperature to 57 ºC there was a rapid initial drop in the biogas yield rate
averaging yield 512.3 l·kg-1·VS-1 and energy value of 10.2 MJ·kg-1·VS-1. In addition, the temperature
fluctuations influence variations of biogas production significantly.