Optimizing residential photovoltaic system size using approximate reasoning

Alternative electrical energy conversion systems employing renewable energy sources suffer significant price disadvantages in relation to those utilizing conventional sources. In an effort to minimize this disadvantage, an evaluation was made of a residential photovoltaic conversion system configured to take advantage of an economic incentive offered by an electrical utility to encourage off-peak energy consumption. Subjective factors in the array sizing decision were evaluated using a fuzzy decision-making process. The alternative does not make economic sense for subjectively acceptable array sizes. A small saving for annual utility bills was obtained utilizing the incentive relative to one not incorporating the utility rate differential, but additional hardware expenses are likely to negate the benefit