Economic assessment of two water heating systems using a simulation model on @RiskTM and their connection with the “gasolinazo” event in México

Abstract

The objective is to analyze the economic feasibility under risk conditions of a water solar heating system. Based on economic and environmental data collected in 2014 and 2015 in Hidalgo State (Mexico), two different ways for heating water for domestic use were compared in the region considering the annual cost criteria. The first scenario (deterministic) analyzes a traditional heating system based on LP gas, while the second scenario considers a solar heating system coupled with an LP gas system, this one to be used as an alternative when there is not enough solar radiation. Both scenarios considerate the investment, operation and maintenance costs, however, the second scenario, which is studied by means of a simulation model constructed in @RiskTM, considers the annual days variability with low solar radiation. For a low level hot water demand (2 people), the results showed that the expected value of the annual cost, of the solar system was lower, up to an annual average of 220 days with low solar radiation.  Also, for a high demand level of hot water (8 people), the annual average cost of the solar system was lower, even though, the average days with low solar radiation were approximately 300. As it is known, in the geographical area where the Hidalgo State is located, the average days with low solar radiation ranges from 30 to 40 annually. Therefore, the results show a considerable annually average saving of $ 2,000.00 and $ 10,000.00 MXP, for a low and high demand level respectively.