Once finished this research, the following facts have been deduced:

Biofuels are a very interesting and feasible substitute for fossil fuels since both use the same logistic infrastructures and they work in the classical internal combustion engine. In case of the implantation of the biofuels the most important economic expense would be the construction of proper production facilities and the cultivation of dedicated crops. The intrinsic drawbacks of the biofuels are mostly environmental, since their use signifies the continuation of the in-city pollution and their production leads to an intensive use of the fertile soil to produce energy, with the obviously consequent terrain damage (and maybe food scarceness), unless energetic companies switched to the cutting edge 2G and 3G methods. The net GHG emission or reduction derived of its use and production is doubtful (it depends on the feedstock obtaining) but, as a rule, better to the fossil counterpart.

The battery electric vehicle is a very promising alternative to the conventional fuels and to the internal combustion tecnologies, yet it offers a higher efficiency, tackles the in-city harmful gas emissions and, in the practise, reduces the net CO2 emissions. The major problem of this technology is its low autonomy, the long recharge time of the batteries and, at the moment, its higher price in comparison to the gasoline/diesel equivalent (plus the cost of replacing the battery stack). The economic advantage of the BEV is that there is not the necessity of deploying a specific network to produce and distribute any fuel since the car can be recharged from the network at home, even though that some public recharge points placed in parking lots would be convenient.

The hydrogen-based fuel cell vehicle, even being widely promoted and investigated by corporations and governments from all the world, is, in base of the data exposed on this work, a worthless, unsustainable, high-cost alternative which offers the advantages of the in-city pollution elimination, a fast energy refilling (compared to the BEV) and an efficiency fairly superior to the ICV, but faces many drawbacks, such as a low autonomy, a total dependence in a huge investment on hydrogen logistic and production infrastructures and a high energetic and ecologic expense during the fabrication of this gas, which has really bad physic proprieties. Besides, the state of the art of this technology is still low, so the production and achieving cost of a FCV is, nowadays, astronomic due to the precious metal that the fuel cell stack contains along with its demonstrative-scale fabrication.

So the global conclusions of this research can be deduced:

Both the battery electric vehicle and the biofuel-fed internal combustion vehicle are the most viable and interesting alternatives to the petroleum derivates for automotion. They will (or can) represent the future generation of power sources for automotion, and gain a huge relevance in the middle or long term. Even though their current higher price and worse performance of availability, the unavoidable rise of the price of the fossil combustibles will lead them to a much important role.

The implantation of the hydrogen-fed fuel cell vehicle, in contrast, has demonstrated to be an unfeasible idea, due principally to the considerable cost of its deployment and the energy expenses of the hydrogen production, added to the problematic physical proprieties of this gas. Hence the FCV is manifestly worse than its alternatives, so it is deductible that it will be abandoned in the middle term in favour of these other ones, which offer much better results.

The area of the alternative and sustainable fuels and technologies for automotion offers a wide list of elements to study from different ambits, namely technical, scientific or economic. During the realisation of this research the author had a special interest inthe practical application of these technologies, so it was intended to perform an implantation study of a BEV in the public bus line which links Falset with the Marçà train station in order to analyse its actual advantages and drawbacks. Unluckily, even though that the necessary data about the current bus, the circuit and the customers was compiled, the author regrets not having been able to carry out this project since it was neither possible to contact the Smith Electric Vehicles company to request the data sheet of the vehicle (Edison Minibus) nor to find any alternative supplier, so this project had to be finally discarded. Due to this fact, the author leaves now the door open to any future technical project about the implantation of these vehicles.

ACKNOWLEDGEMENTS

Before finishing this exposition I would like to show gratitude to my tutors Yolanda Beltran, former director of the Institut Priorat, and Enric Armengol, technology teacher in the same institute, for their constant guidance and advisory through the realisation of this research, as well as their constant interest and implication which I really appreciated. Also:

To Jaume Escoda, informatics teacher of the Institut Priorat, for guiding me during the composition of this webpage and publishing this work on the web.

To Goyo Vizcaíno, former teacher of the IES Priorat, who advised me about the procedures for performing the survey in the Saló de l'Automòbil in Barcelona.

To Damià Bello, Toyota Autoforum vendor (in Reus) who clarified me some basic concepts about alternative fuels in the earlier stage of this research.

To Adolf Pellejà, councilman of serveis municipals i camins of Falset's local council, and all the Transports Pellejà personnel, who helped me agreeably to obtain the information that I requested to carry out an additional implantation study which, unluckily, I couldn't complete due to the impossibility of contacting with the Smith Electric Vehicles company staff.

To the kind help of Magda Blasco, English teacher of the IES Priorat who proposed me to do the present research in this language, and offered herself as a corrector.

To the constant back of my family, whose aid and optimism made me progress in this research in front of the difficulties and the doubts I had to affront during all this time. I am especially grateful to them for supporting me in all the decisions I made, as well as for facilitating me the assistance to the Saló de l'Automòbil , along with many other facts.