Modern methods for estimating the levels of world production for the alternative fuels

Alternative fuels for spark and compression ignition engines have become very important due to the increase of the environmental protection concerns, the need to reduce dependence on oil consumption, and other socio-economic considerations. The main alternative fuels currently used are natural gas, liquefied petroleum gas (LPG) and biofuels, such as vegetable oils and alcohols (bioethanol), etc. The paper starts with a review of the present and future alternative fuels for the combustion engines, in comparison with the renewable resources. The review is based on the recent available and data research results. The authors of the paper conducted some analysis for estimating the alternative fuels production level based on mathematical models, which are using parameters and properties as described by the current fuel standards. Applying neural network techniques, mainly the multilayer perceptron, the authors make estimations of the weight of the alternative fuels production in total fuels, by categories, in annual growth scenarios of 1 %, 1.5 % and 2 %, respectively, for 2019-2030, with an extrapolation of the data until 2100, when it is assumed that the reserves of non-renewable resources (oil, coal and natural gas) will be on the verge of depletion.