Guilherme, R. and El Gamal, G., "Estimating Method for the Avoided Non-Recyclable CO2 by the Use of Brazilian Ethanol in Flex Fuel Vehicles," SAE Technical Paper 2012-36-0505, 2012, doi:10.4271/2012-36-0505.
The introduction of the flexible fuel vehicles in Brazil had the first objective to protect the customer against fuels - commercial gasoline (E22) and hydrated ethanol (E100 or AEHC) - price variations. Nevertheless, while the Flex technology became dominant in the Brazilian market, the environmental aspect of the possibility of using a renewable fuel, ethanol from sugar cane, increased in importance due to the reduction in non-recyclable CO₂ and its benefits for the greenhouse effect. The objective of this article is to propose a practical method to quantify the avoided CO₂ using available engine management system parameters, basic chemical calculations, literature information and simplifying assumptions. The resulting equations show that it is possible to have a practical avoided-CO₂ calculation procedure which can be performed on-board and used for customer information and for quantifying the environmental advantage of using ethanol in fleets of flexible fuel cars.