For decades, solar-cell efficiencies have remained below the thermodynamic limits. However, new approaches to light management that systematically minimize thermodynamic losses will enable ultrahigh efficiencies previously considered impossible.

/pdf/photonic-design-principles-for-ultrahigh-efficiency-2kbdeerbd2.pdf

Photonic design principles for ultrahigh-efficiency photovoltaics

The use of solar energy in recent years has reached a remarkable edge. The continuous research for an alternative power source due to the perceived scarcity of fuel fossils is its driving force. It has become even more popular as the cost of fossil fuel continues to rise. The earth receives in just 1 h, more energy from the sun than what we consume in the whole world for 1 year. Its application was proven to be most economical, as most systems in individual uses requires but a few kilowatt of power. This paper reviews the present day solar thermal technologies. Performance analyses of existing designs (study), mathematical simulation (design) and fabrication of innovative designs with suggested improvements (development) have been discussed in this paper.

A review of solar thermal technologies

Global energy demand and environmental concerns are the driving force for use of alternative, sustainable, and clean energy sources. Solar energy is the inexhaustible and CO2-emission-free energy source worldwide. The Sun provides 1.4 � 10 5 TW power as received on the surface of the Earth and about 3.6 � 10 4 TW of this power is usable. In 2012, world power consumption was 17 TW, which is less than 3.6 � 10 4 TW. Photovoltaic (PV) cells are the basic element for converting solar energy into electricity. PV cell technologies, energy conversion efficiency, economic analysis, energy policies, environmental impact, various applications, prospects, and progress have been comprehensively reviewed and presented in this paper. This work compiles the latest literature (i.e. journal articles, conference proceedings, and reports, among others) on PV power generation, economic analysis, environmental impact, and policies to increase public awareness. From the review, it was found that PV is an easy way to capture solar energy where PV based power generation has also rapidly increased.

/pdf/global-prospects-progress-policies-and-environmental-impact-56g8a201aj.pdf

Global Prospects, Progress, Policies and Environmental Impact of Solar Photovoltaic Power Generation

With the aim of utilizing the infrared region of solar radiation to improve solar cell performance, significant progress, including theoretical analysis and experimental achievement, has been made in the field of up-conversion for photovoltaic applications. This Research News article reviews recent progress in the development of rear-earth (RE) ion doped up-conversion materials for solar cell applications. In addition, new trends for RE-ion-doped phosphors are briefly discussed, among them trivalent RE-ion-doped up-conversion materials for organic solar cell applications.

Rare-earth ion doped up-conversion materials for photovoltaic applications.

Performance of a concentrating photovoltaic/thermal solar collector

The development of an outdoor test station for accurate in situ I-V curve measurements of photovoltaic (PV) modules is described. The modules are installed in an open-rack configuration at the University of Agder in Southern Norway. Seven new and three aged PV modules of different type and make are being tested, including mono-and multicrystalline silicon from differing manufacturing routes, triple-junction amorphous silicon, and CIS. Data acquisition is controlled with a multichannel electronic load system and LabVIEW software, recording high-resolution I-V curves at one-minute intervals. Between I-V curve sweeps, each module is operated at the maximum power point. Characteristic electrical parameters are extracted and stored together with values of module temperatures and in-plane solar irradiance, the latter recorded at sub-second resolution. The paper describes the experimental set-up in more detail, discusses some local environmental effects, and presents a sample of test results.

Development of a test station for accurate in situ I-V curve measurements of photovoltaic modules in Southern Norway

The massive growth of PV farms, both in number and size, has motivated new approaches in inspection system design and monitoring. This paper presents a review of imaging technologies and methods for analysis and characterization of faults in photovoltaic (PV) modules. The paper provides a brief overview of PV system (PVS) reliability studies and monitoring approaches where fault related PVS power loss is evaluated. Research on infrared thermography (IRT) and luminescence imaging technologies is thoroughly reviewed, with focus on ease of implementation, efficiency and unmanned aerial system (UAS) compatibility. Furthermore, the review will provide novel insight into state-of-the-art electroluminescence (EL), photoluminescence (PL) and ultraviolet fluorescence (UVF) imaging, and how to interpret these images. The development of imaging techniques will continue to be an attractive domain of research that can be combined with aerial scanning for a cost-effective remote inspection that enable reliable power production in large-scale PV plants. 

Inspection and condition monitoring of large-scale photovoltaic power plants: A review of imaging technologies

A method of creating rugate interference filters that have flat-topped
reflectance across an extended spectral region is presented The method
applies known relations from the classical coupled wave theory to develop a
set of equations that gives the spatial frequency distribution of rugate cycles
to achieve constant reflectance across a given spectral region Two examples
of the application of this method are discussed: a highly reflective coating
for eye protection against harmful laser radiation incident from normal to 45°,
and a spectral beam splitter for efficient solar power conversion

Flat-topped broadband rugate filters

It is intended to build and test a Multi Tower Solar Array (MTSA) prototype at the new CSIRO Energy Technology Centre in Newcastle, New South Wales, Australia. The MTSA concept can achieve very high ground or roof coverage (>90%) by using an array of small towers or posts 8 – 12 m high on which receivers are mounted. The aim of the MTSA is to address medium sized urban combined heat and power markets using a versatile optical system that can incorporate a variety of receiver types, either individually or in combination. This paper describes the new technologies to be tested.

Multi Tower Solar Array Project

The research community and stakeholders in the building sector seek information on the performance and reliability of PV systems in the built environment and the best solutions for maximum energy production. This paper presents results from collected information on a representative selection of existing building integrated (BIPV) and building applied (BAPV) photovoltaic systems in Norway. The work is part of a national project that aims at developing robust BIPV-solutions suitable for a Norwegian climate. The project also aims at identifying the main building-technical and architectural integration challenges for BIPV. A questionnaire has been developed to interview key personnel involved in the design, installation and operational phases, and a database is under development to build a wider knowledge base for the expected performances of different system types and geographical locations. Performance is evaluated in terms of energy production, specific yield, and performance ratio (PR) in cases where irradiation data is available. Data collected so far indicate a relatively large spread in annual specific yield with typical values in the 700–900 kWh/kWp range. A well-functioning system without significant shading may achieve PR above 0.85, in agreement with similar findings for Europe. Five selected cases are presented in more detail. The lessons learned provide useful input for the development of new guidelines and system requirements for BIPV in a nordic climate.

Anne Gerd Imenes

Papers

Development of a test station for accurate in situ I-V curve measurements of photovoltaic modules in Southern Norway

Inspection and condition monitoring of large-scale photovoltaic power plants: A review of imaging technologies

Flat-topped broadband rugate filters

Multi Tower Solar Array Project

Performance of BIPV and BAPV installations in Norway