Solar Energy Perspectives - IEA

Chapter 6: Solar photovoltaics
Figure 6.2 Polysilicon spot and weighted average forward contract prices (USD/Kg)
Long term
contract price
as of early 2011
Spot price
400
350
300
250
200
150
100
50
0
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015
Source: Bloomberg New Energy Finance.
Key point
Figure 6.2
A shortage of purified silicon stopped PV cost reductions from 2004 to 2007.
Since then, costs fell by 40% in only two years – 2008 and 2009 – and PV costs went back
to the previous track corresponding to a learning rate of 19.3% over 34 years (1976 to 2010)
(Figure 6.3). Currently, the lowest manufacturing cost of PV modules is USD 0.74 per wattpeak
(USD/W p – a measure of the nominal power of a PV device), achieved by the cadmiumtelluride
(CdTe) PV company First Solar, bringing the cost of large-scale systems around USD
2/W p . Silicon PV modules are about USD 1.80/W p , and single-crystalline silicon (sc-Si)
utility-scale systems at USD 3.00/W p .
The PV learning rate is the highest ever seen in the energy world. By contrast, on the basis
of past experience, the WEO 2010 assumes, for decades to come, learning rates of 1% for
hydro power, 5% for biomass and geothermal, 7% for wind onshore, 9% for wind offshore,
10% for CSP, 14% for marine energy, and 17% for PV. The rapid learning with PV probably
arises from the fact that PV technologies are a spinoff from semi-conductor technologies.
Even higher learning rates have been recorded for other semi-conductor based
technologies: 45% for dynamic random-access memory (DRAM) chips, 35% for flat panel
displays. Very steep learning curves for electronic devices are based on the integration
density of transistors. Except for cooling needs, there is no reason to have large surface
areas, contrary to displays and PV cells, which may explain the less rapid cost reductions
in their cases.
State of the art and areas for improvement
The various photovoltaic technologies are at differing levels of maturity – and all have
a significant potential for improvement. Increased and sustained research, development and
demonstration (RD&D) efforts are needed over the long term in order to accelerate cost
reductions and the transfer to industry of the current mainstream technologies, to develop
and improve medium-term cell and system technologies, and to design novel concepts and
bring them to industrial use.
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© OECD/IEA, 2011