Review of the energy and economic parameters involved in the effectiveness of grid-connected PV systems installed in multi-storey buildings

The assessment of PV energy in an urban context is extremely complex because many factors have to be considered. Moreover, when the purpose is calculating the realistic amount of the electricity demand of a city that can be covered by the photovoltaic generation, it is necessary to estimate the number of photovoltaic systems whose installation is economically advantageous. Such a topic requires an economic analysis, which is affected by the number of energy and economic parameters involved and the values assigned to them to perform calculations. Some parameters are perfectly known and unvarying, like the paid incentives. Adversely, some parameters, like the efficiency degradation of photovoltaic panels, can only be supposed. Other parameters require some information that is specifically related to each particular photovoltaic system. With the aim of estimating the influence of the manifold energy and economic parameters that characterize how photovoltaic penetration develops in urban areas, a specific study was conducted for a city in the south of Italy. A sensitivity analysis was carried out in order to verify parameters have an irrelevant influence and what are the parameters whose definition can be a crucial element of the energy and economic analysis of photovoltaic systems because dramatically impact on the results. The presented study represents a valuable help for photovoltaic systems designers and energy decision-makers because it permits to evaluate the impact of the deviations of the main parameters on the profitability of photovoltaic systems and the role played by them in the effectiveness of the energy policies implemented to achieve the required shares of electricity demand coverage.