Toward an integrated assessment of the performance of photovoltaic power stations for electricity generation

In this paper a photovoltaic (PV) technologies for electricity generation accounting scheme is proposed
and applied. The adopted scheme aims to overcome limitations of conventional indicators such as
EROI (Energy Return on Investment) and EPBT (Energy Payback Time) and to present a more comprehensive
description of energy and material transformations. The proposed methodology is based on the
Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) approach. In this
work, four dimensions of sustainability which should be addressed for the purpose of identifying the
limiting factors of photovoltaic systems for electricity production are presented: Energy and Material
Accessibility; Environmental Health Desirability; Technological Achievability; and Socioeconomic
Acceptability. In relation to these four dimensions, the direct and indirect requirements of flow and fund
elements (silver, energy carriers and water as flows; human time and land as funds) in photovoltaic
power stations based on crystalline silicon wafer cells are evaluated and the implications of the overall
performance and limitations of the present PV systems are discussed. These parameters are also compared
with other electricity production technologies as well as benchmarked against the performance
of the energy and mining sector of a modern country (Spain). It is concluded that the availability of silver
could constrain photovoltaic cell manufacturing. Furthermore, the low power density of photovoltaic
installations could drive a remarkable land rush. Finally, the human labor allocated in the fundmaking
process could represent a serious constraint in respect to the requirements of the metabolism
of modern societies.