NOVELTY - The supply unit (120) has filtering and compressing unit (122) whose pyrolysis gas filter unit (126) removes tar from received pyrolysis gas and compressor unit (128) pressurizes pyrolysis gas. A pyrolysis gas regulating unit (124) regulates a flow of pyrolysis gas leaving regulating unit. A pyrolysis gas admission valve (140) controls amount of pyrolysis gas provided to charge air system. A charge air passage (115) is fluidly connected to charge air system. The pyrolysis gas admission unit is fluidly connected to admission valve to provide pyrolysis gas to passage.    USE - Pyrolysis gas supply unit for providing pyrolysis gas into charge air system of internal combustion engine (claimed).    ADVANTAGE - The over all efficiency of pyrolysis based power plant technology is improved. Safe operation of the internal combustion engine with the various fuel types and combination is performed.    DETAILED DESCRIPTION - The pyrolysis gas supply unit provides pyrolysis gas into a charge air system (161) of an internal combustion engine (162) operated with a liquid fuel. A pyrolysis gas inlet (121) receives pyrolysis gas. The pyrolysis gas filter unit is provided with a centrifuge based filter, a cyclone based filter and a rotating net based filter. The compressor unit is provided with rotary compressor, Root blower, small ventilator and screw spindle compressor. The pyrolysis gas regulating unit is provided with a service valve (130), a pyrolysis gas purity indicator and safety filter (132), pressure sensor (135) based control valve, shut-off valve, a venting valve, and a shut-off valve control unit (138). A pyrolysis gas admission unit (142) is provided with a cylinder head with release nozzle opening into the charge air passage. A pipe section (114) is provided with a nozzle (116) opening into the charge air passage. An insert element for mounting within a charge air manifold of the internal combustion engine is provided with cylinder specific openings for releasing the pyrolysis gas into the charge air within the charge air manifold. The pyrolysis gas admission valve and pyrolysis gas admission unit are provided for each cylinder unit of the internal combustion engine to enrich charge air with pyrolysis gas. INDEPENDENT CLAIMS are included for the following:    (1) an internal combustion engine system has a compressor system that compresses charge air. The pyrolysis gas supply unit provides pyrolysis gas upstream and downstream and between stages of the compressor system into charge air system. The compressor system compresses the pyrolysis gas to a pressure of up to 0.3 bar when the pyrolysis gas is provided upstream of compressor system up to 4 bar 3.5 bar. A control unit (170) controls the compressor unit and the pyrolysis gas admission valve to adapt the pressure of the pyrolysis gas and the amount of the pyrolysis gas provided by the pyrolysis gas admission valve into the charge air system in dependence of the load of the internal combustion engine. The control unit controls the energy content provided by the pyrolysis gas to the combustion to be in the range of about 10 % - 35 % of the total energy content of fuel combusted in the internal combustion engine. The control unit controls the compressor system compressing pyrolysis gas in dependence of load of the internal combustion engine, an output and/or intermediate pressure of the compressor system, an amount of liquid fuel provided for injection by the liquid fuel system. A pyrolysis gas intermediate storage unit fluidly connected to pyrolysis gas supply unit downstream of the compressor unit stores filtered and pressurized pyrolysis gas. The internal combustion engine operates on pyrolysis oil based fuel, crude oil based fuel and ethanol/castor oil based fuel.; and    (2) the method for operating internal combustion engine based on pyrolysis based fuels involves enriching charge air with pyrolysis gas and combusting pyrolysis oil based fuel, crude oil based fuel, and/or ethanol/castor oil based fuel with the pyrolysis gas enriched charge air. The charge air is enriched with pyrolysis gas downstream of a compressor system of the internal combustion engine. The energy content provided by the pyrolysis gas to the combustion is controlled to be in the range of about 10 % - 35 % such as between 20 % - 25 % of the total energy content of fuel combusted in the internal combustion engine. The pyrolysis gas is compressed in dependence of load of internal combustion engine, an output and intermediate pressure of the compressor system and amount of liquid fuel provided for injection. A detonation is monitored within a cylinder unit and a temperature of the charge air and the pyrolysis gas.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the pre-charge air compressor supply system for providing pyrolysis gas to the internal combustion engine.    Pipe section (114)    Charge air passage (115)    Nozzle (116)    Pyrolysis gas supply unit (120)    Pyrolysis gas inlet (121)    Filtering and compressing unit (122)    Pyrolysis gas regulating unit (124)    Pyrolysis gas filter unit (126)    Compressor unit (128)    Service valve (130)    Pyrolysis gas purity indicator and safety filter (132)    Pressure sensor (135)    Shut-off valve control unit (138)    Pyrolysis gas admission valve (140)    Pyrolysis gas admission unit (142)    Charge air system (161)    Internal combustion engine (162)    Control unit (170)