Expert assessments of future photovoltaic technologies.

Subjective probabilistic judgments about future module prices of 26 current and emerging photovoltaic (PV) technologies were obtained from 18 PV technology experts. Fourteen experts provided detailed assessments, including likely future efficiencies and prices under four policy scenarios. While there is considerable dispersion among the judgments, the results suggest a high likelihood that some PV technology will achieve a price of $1.20/Wp by 2030. Only 7 of 18 experts assess a better-than-even chance that any PV technology will achieve $0.30/Wp by 2030; 10 of 18 experts give this assessment by 2050. Given these odds, and the wide dispersion in results, we conclude that PV may have difficulty becoming economically competitive with other options for large-scale, low-carbon bulk electricity in the next 40 years. If $0.30/Wp is not reached, then PV will likely continue to expand in markets other than bulk power. In assessing different policy mechanisms, a majority of experts judged that R&D would most increase efficiency, while deployment incentives would most decrease price. This implies a possible disconnect between research and policy goals. Governments should be cautious about large subsidies for deployment of present PV technology while continuing to invest in R&D to lower cost and reduce uncertainty.