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Ethanol is one of the most promising renewable fuels for decarbonizing off-road and heavy-duty engine applications due to a well-established industry with high production capacity, existing distribution infrastructure, low carbon intensity and reasonable cost. However, several properties, such as ignitability, energy density and lubricity, are not suitable for mixing-controlled combustion in modern compression-ignition (CI) engines as those used in most off-road and heavy-duty applications, with ignitability being the main technical barrier for ethanol compression-ignition. In this work, ethanol MCCI is enabled by doping ethanol with 2-ethylhexyl nitrate (EHN), an inexpensive cetane improver typically used with diesel fuel. A medium-duty single-cylinder research engine is operated at low- and part-loads with boundary conditions representative of diesel engine operation. Production engine geometry was used to test drop-in potential of the fuel. Three EHN levels are tested, 3 % vol , 5 % vol and 7 % vol. The experiments demonstrated successful MCCI combustion of ethanol within acceptable combustion control range, constrained by the transition to kinetically-controlled combustion for highly advanced injection timings and high cycle-by-cycle variability of the pilot injections for the most retarded injection timings. Results show that the combustion control range increases as the EHN content increases due to the higher fuel reactivity. Under the part-load, ethanol combustion shows higher thermal efficiency than that of diesel due to lower heat transfer loss. At low load, ethanol combustion is only achievable with 7 % vol EHN and leads to lower thermal efficiency than diesel mainly due to inefficient combustion. The impact of increasing the compression ratio was also investigated, resulting in stable ethanol combustion at low load with 3 % vol EHN. Particulate matter emissions of ethanol are much lower than the current US off-road limit and the 2027 US EPA HD limit, with NO x emissions within the range of those of diesel. Finally, analysis of exhaust gas emissions shows that unburned hydrocarbons of ethanol combustion are composed mainly by ethanol, ethene and acetaldehyde. • Ethanol mixing-controlled compression ignition (MCCI) combustion is achieved. • Multiple injection strategy is introduced for stable operation with ethanol. • The effect of an ignition enhancer (EHN) on ethanol combustion is investigated. • Ethanol improved heat transfer loss and particulate matter emissions. • High compression ratio allowed stable operation with less ignition enhancer. [ABSTRACT FROM AUTHOR]