DIESEL-ETHANOL TRUCK ENGINE FOR BRAZILIAN ETHANOL PLANTS: STRATEGY FOR ECONOMIC GAIN AND CLIMATE CHANGE MITIGATION

Resumo

Dual-fuel diesel engine with ethanol injection is one of the promising technologies to allow ethanol use in commercial vehicles. Its main benefit is the possibility to calibrate the engine with similar combustion efficiency as diesel, but its challenge is to achieve higher substitution rates of diesel by ethanol. To check these limits, in this paper one engine prototype was built, calibrated and installed in a truck, to be used in duty cycle of the Brazilian ethanol industry (36 trips with total load of 63 ton and 28 trips with total load of 25 ton). In the tests it was evaluated: a) the performance of the diesel-ethanol engine in real conditions, b) the economic feasibility related to the ethanol costs, and c) the CO₂ emission reduction via fuel switch (fossil by renewable fuel) from the United Nations Framework Convention on Climate Change methodology. As result of the tests, it was achieved slightly better fuel consumption in the diesel-ethanol mode, with an average substitution rate of 38%. In addition, this result conducts to a positive cash flow of 8%, if the ethanol costs were a half of the diesel price (limit value). For higher ethanol prices, the economic feasibility is marginal or non-existing and. In this case, Clean Development Mechanism (CDM) project could be decisive to the implementation of this technology in large scale in the Brazilian ethanol industry. The project can be justified by the 29% of CO₂ emissions reduction due to the dual-fuel engine in comparison to the diesel mode.