A “Moore's Law”-like approach to roadmapping photovoltaic technologies

The photovoltaics industry has made steady progress over the past 40 years toward increasing solar cell and module efficiencies while incrementally lowering the initial installed cost of photovoltaic systems. These two factors dominate in lowering the cost of solar electric energy (in ¢/(kW-h)) as it approaches parity in cost with electric energy produced conventionally using coal, nuclear, or natural gas. An interesting question regards whether there is a relationship that describes the evolution of photovoltaics Levelized Cost of Energy (LCOE) similar to Moore's Law characterization of microelectronics evolution of transistor size and density. With some caveats, we believe a similar PV relationship can be defined; the purpose of this paper is to propose and discuss a basis for this relationship. To achieve parity the installed cost of PV systems needs to be reduced by 50% from approximately $600/m2 to $300/m2 with a concurrent increase in c-Si module efficiency to 24% AM1.5. The trajectories in time needed to drive a technology roadmap for lowering the installed cost and for increasing the module efficiency to achieve parity are discussed. Also, a new methodology for calculating LCOE for PV systems is proposed and discussed in Appendix.