STUDY ON CONVERSION OF CONVENTIONAL GENERATOR SET TO FUEL WITH GASES FROM BIOMASS

Abstract

This paper presents experimental study on conversion of diesel generator engine to fuel with gases from biomass. The study was conducted on 3 phase generator set equippted Isuzu 4JJ1-T engine which has displacement of 3.0 liter and uses common rail system and tubocharger. The structure and main
symtems of the original engine were modified to work with biogas fuel. Specifically, the gases supply and ignition system are equipped to replace the original common rail system of the engine. In order for the engine to work with biogas without knocking, compression ratio of the engine is reduced from 17.5 to 13.0 by using a cylinder head gasket. In addition, the engine is equipped with an electronic speed controler to stabilize frequency of generation as the external load changes. After the conversion, the generator achieved a max power of 31.14kW with 64% CH4 by volume in biogas fuel, equivalent to 85% of rated power of the original engine. Experimental results also show that the energy conversion efficiency is 1.17, equivalent to 1m3 of biogas with 64% CH4 will generate 1.17kW of electricity. Using biogas fuel on generator sets has expand widely the usage of renewable energy sources and environmental protection and also reduce electricity consumption on small and medium farms.