Page 11 - RSE - Results of the Apollon Project

Results of the APolloN PRoject ANd coNceNtRAtiNg PhotovoltAic PeRsPective

2) CPV technology needed to be more competitive with the “fat plate” module photovoltaic technology to achieve a
deeper penetration into the energy market. The research activities of the APOLLON Project were, therefore, based
on two main documents: the Photovoltaic Technology Research Advisory Council report, issued in 2005, under the title:
A Vision for Photovoltaic Technology; and the Strategic research agenda for Photovoltaic Solar Energy Technology issued in
2007 and again later in 2011.
The frst allowed for a defnition of the general overall economic objective that CPV technology should achieve,
while the second helped to set the objective for each individual component of the CPV systems. The Photovoltaic
Technology Research Advisory Council report stated that the cost of generating PV electricity from grid-connected
systems would be halved by 2010-2015. This meant that the typical “fat plate” turnkey system price of 5 Euros/W
could be reduced to 2.5 Euros/W within the aforementioned period. This forecast had to be kept in mind to
address the economic horizon for CPV: it was clear that CPV systems could become a winning photovoltaic
technology if a cost of 2 Euros/W was achieved in the same period.
The main concern of the APOLLON project was, therefore, to set up research activities aimed at reaching
better CPV module performance and, at the same time, achieving a substantial cost reduction. The Strategic
research agendas for Photovoltaic Solar Energy Technology have been used as main reference documents to set the
project objectives for each system component: the solar cells, the optic concentrator, the module and the tracker.
Therefore, under the APOLLON project an integrated approach was adopted, involving the entire stakeholders
chain, from Universities, SMEs, industries to End Users to ensure the right expertise mixture was there to face all
the critical technological and economic issues related to each component of the CPV system.

3) CPV technology needed to overcome the issue of its perceived lack of reliability. Demonstrating the long-term
stability of CPV systems was an important goal. It demanded accelerated testing procedures and long-term
outdoor testing. The existence and acceptance of well-designed and robust standards covering all aspects of
Concentrator PV systems was still missing at the starting date of the project, therefore, considering that working
on norms and standard was essential to a successful commercialisation of CPV technology, testing activities
played a very important role in the APOLLON project.
Namely, accelerated testing of receivers were planned, following the test standard described in IEC 62108;
partners with experience in space applications, where severe tests on solar cells are routinely carried out, were
also involved. Furthermore, given that the methodology for outdoor module testing was still being evaluated
by the PV community, the APOLLON Project adopted a Round-Robin CPV module testing methodology, and new
testing methodologies were also applied. This way, the cooperation of the different Partners involved in outdoor
CPV characterisation provided new characterization methods useful for the development of standardised tests,
and allowed reliable data to be provided for the evaluation of module performance and energy payback time.

4) While in the USA the Arizona Public Service (APS) had been installing and routinely operating Amonix high CPV
systems since early 1991 to support the industrialisation of this technology , in Europe an important initiative for
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sustaining the industrial development of CPV sector had only been launched at the end of 2006 at the Institute
for Concentrated Photovoltaic System (ISFOC). To further favour the industrialisation of CPV technology, the
APOLLON project involved an important end-user. CPV technology had better success as utility scale application,
therefore the presence of an end-user in the Consortium could foster stronger confdence in CPV technology
in this application sector and, subsequently, its future deeper penetration into the energy production market.
In order to ease the way towards an industrialization of the CPV technology, development activities were also
addressed to ensure a higher level of integration between optics and receivers, setting up technologies with a low
environmental impact.

With due attention to the above mentioned objectives and with the aim of giving CPV industries the possibility to
check the technological improvements on the feld within a reasonable time scale, without risking hindering the path
towards more attractive solutions which require a longer development period, the implementation of the APOLLON
project has been carried out in two phases. The frst envisioned the optimization of existing CPV technologies,
from the cell component up to the system level, while in the second one the search for more advanced solutions
and a more substantial progress beyond the state-of-the-art were pursued. The following paragraphs outline the
results achieved in the APOLLON project during its two development phases as well as the challenges that in the
Consortium’s view are still to be tackled for a successful wide commercialization of the CPV technology.

9 APS installation and operation of 300kW of Amonix high concentration PV systems, Proceeding s of IEEE 2002.

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