Análise técnico-econômica do uso de gás natural para aplicações de climatização no setor comercial brasileiro

Abstract

Since the end of the last century that Brazil as a whole, and more specifically the northeast region of this country, are passing by constant concerns regarding the electricity supply. The increasing demand, mainly located at commercial sector, combined with a possible exhaust of the hydric potential, associated with insufficient investments in generation, transmission and distribution of electrical power made this situation even more serious. To offset this critical situation between supply and demand of electricity, are being built, since the beginning of this century, small hydroelectric plants, wind generators and mainly thermoeletric power plants that uses natural gas as their energy input. However, according to the current model for the use of energy resources, the construction of these power plants will require simultaneous investments in order to increase the transmission and distribution lines of electrical energy, so that it reaches the final customer. This work aims to study the technical and economic feasibility for the direct application of natural gas to the climate control end customers, for applications located at the commercial sector, this insertion will be done by the use of "chillers" that operate according to an absorption cycle, eliminating additional expenses with electricity transmission and distribution lines expansion, as well as the energy losses resulting from these two processes. The feasibility study, based in the actual taxes of electricity and natural gas applied in the Bahia state, made technical and economic comparisons between natural gas "chillers" with their electrical equivalents, that works under vapour compression cycle, using parameters such as coefficient of performance, exergetic efficiency, operational costs and payback time. The conclusion is that the use of natural gas for climate control applications in commercial sector are technically feasible, however, from the economic point of view, reductions on the natural gas prices around 2,5% are needed to make feasible this kind of energy input for the commercial applications listed.