its of each fuel over a 24 month period. Fuel costs per mile, emission levels, maintenance problems, and refitting costs will all be considered in the study. Although the focus of this current study with respect to alternative fuels is on methanol, alcohol gasoline mix, and liquid natural gas, research is also progressing rapidly on solar powered electric vehicles using battery powered electricity produced through photovoltaic conversion (Watanabe, 1992, pp. 60 61). Photovoltaic technology is the principal method through which solar radiation is transformed into electric power (Mersel, 1993, pp. 46 51. Solar power is attracting attention as an inexhaustible source of clean energy (Unemura, 1992, pp. 38 39). A major task involved in gaining acceptance for the development of solar generated electrical power is the improvement of the economic efficiency of the process. Nevertheless, average insolation levels characterizing global areas that are home to the great majority of the world's population suggest that solar conversion technologies hold great potential for the future (Kuhne and Aulich, 1992, pp. 847 860).
Photovoltaic technology is the most promising of a wide variety of renewable energy project now in progress (Hamakawa, 1992, pp. 41 46). Photovoltaic technology taps a clean and inexhaustible power source. The technology is silent, has no moving parts, and is almost maintenance free. Photovoltaic conversion is size independent with respect to efficiency, and collection and storage devices provide benefits through mass scale production. Photovoltaic technology also functions in conditions of diffuse light sources. The major barrier to the wide spread application of photovoltaic technology has been the relatively high price of solar cell modules. This problem, however, is the subject of intensive research in the mid 1990s.
Each year, the amount of energy that reaches the surface of the earth from the sun exceed...