V-2 - Energy Pay-Back Time and CO2 Emissions of PV Systems

Abstract

This chapter presents estimates of the energy requirements for manufacturing of photovoltaic (PV) systems and evaluates the energy balance for a few representative examples of PV system applications. It also investigates the effects of future enhancements in PV production technology and PV system technology in order to assess the long-term prospects of PV technology as a candidate for a sustainable energy supply and for CO2 mitigation. The chapter considers mainly grid-connected PV systems, because these systems have the largest potential in terms of long-term, global energy supply, and CO2 mitigation. With respect to standalone PV systems the energy balance depends very much on the specific application. The chapter begins with a brief discussion on energy analysis methodology and some general assumptions. It then discusses the energy requirements for the components of PV systems. The energy balance for grid-connected PV systems is presented, followed by an outlook for future PV systems. The chapter also assesses the potential for CO2 mitigation using PV systems.