Showing papers on "Solar energy published in 2010"
TL;DR: The biggest challenge is whether or not the goals need to be met to fully utilize solar energy for the global energy demand can be met in a costeffective way on the terawatt scale.
Abstract: Energy harvested directly from sunlight offers a desirable approach toward fulfilling, with minimal environmental impact, the need for clean energy. Solar energy is a decentralized and inexhaustible natural resource, with the magnitude of the available solar power striking the earth’s surface at any one instant equal to 130 million 500 MW power plants.1 However, several important goals need to be met to fully utilize solar energy for the global energy demand. First, the means for solar energy conversion, storage, and distribution should be environmentally benign, i.e. protecting ecosystems instead of steadily weakening them. The next important goal is to provide a stable, constant energy flux. Due to the daily and seasonal variability in renewable energy sources such as sunlight, energy harvested from the sun needs to be efficiently converted into chemical fuel that can be stored, transported, and used upon demand. The biggest challenge is whether or not these goals can be met in a costeffective way on the terawatt scale.2
8,037 citations
TL;DR: The past success in organic light-emitting diodes provides scientists with confidence that organic photovoltaic devices will be a vital alternate to the inorganic counterpart, and the easiness of the fabrication holds the promise of very low-cost manufacturing process.
Abstract: Sun is the largest carbon-neutral energy source that has not been fully utilized. Although there are solar cell devices based on inorganic semiconductor to efficiently harvest solar energy, the cost of these conventional devices is too high to be economically viable. This is the major motivation for the development of organic photovoltaic (OPV) materials and devices, which are envisioned to exhibit advantages such as low cost, flexibility, and abundant availability. [1] The past success in organic light-emitting diodes provides scientists with confidence that organic photovoltaic devices will be a vital alternate to the inorganic counterpart. At the heart of the OPV technology advantage is the easiness of the fabrication, which holds the promise of very low-cost manufacturing process. A simple, yet successful technique is the solution-processed bulk heterojunction (BHJ) solar cell composed of electron-donating semiconducting polymers and electron-withdrawing fullerides as active layers. [2] The composite active layer can be prepared as a large area in a single step by using techniques such as spin-coating, inkjet-printing, spraycoating, gravure-coating, roller-casting etc. [3] In the last fifteen years, a significant progress has been made on the improvement of the power-conversion efficiency (PCE) of polymer BHJ solar cells, and the achieved efficiencies have evolved from less than 1% in the poly(phenylene vinylene) (PPV) system in 1995, [2] to 4‐5% in the poly(3-hexylthiphene) (P3HT) system in 2005, [4] to around 6%, as reported recently. [5] However, the efficiency of polymer solar cells is still significantly lower than their inorganic counterparts, such as silicon, CdTe and CIGS, which prevents practical applications in large scale.
3,602 citations
TL;DR: The Scope of Review: Large-Scale Centralized Energy Storage, Chemical Energy Storage: Solar Fuels, and Capacitors 6486 5.1.2.
Abstract: 1. Setting the Scope of the Challenge 6474 1.1. The Need for Solar Energy Supply and Storage 6474 1.2. An Imperative for Discovery Research 6477 1.3. Scope of Review 6478 2. Large-Scale Centralized Energy Storage 6478 2.1. Pumped Hydroelectric Energy Storage (PHES) 6479 2.2. Compressed Air Energy Storage (CAES) 6480 3. Smaller Scale Grid and Distributed Energy Storage 6481 3.1. Flywheel Energy Storage (FES) 6481 3.2. Superconducting Magnetic Energy Storage 6482 4. Chemical Energy Storage: Electrochemical 6482 4.1. Batteries 6482 4.1.1. Lead-Acid Batteries 6483 4.1.2. Alkaline Batteries 6484 4.1.3. Lithium-Ion Batteries 6484 4.1.4. High-Temperature Sodium Batteries 6484 4.1.5. Liquid Flow Batteries 6485 4.1.6. Metal-Air Batteries 6485 4.2. Capacitors 6485 5. Chemical Energy Storage: Solar Fuels 6486 5.1. Solar Fuels in Nature 6486 5.2. Artificial Photosynthesis and General Considerations of Water Splitting 6486
2,570 citations
TL;DR: By using a solar cavity-receiver reactor, the oxygen uptake and release capacity of cerium oxide and facile catalysis at elevated temperatures to thermochemically dissociate CO2 and H2O, yielding CO andH2, respectively were combined and stable and rapid generation of fuel was demonstrated over 500 cycles.
Abstract: Because solar energy is available in large excess relative to current rates of energy consumption,
effective conversion of this renewable yet intermittent resource into a transportable and
dispatchable chemical fuel may ensure the goal of a sustainable energy future. However, low
conversion efficiencies, particularly with CO_2 reduction, as well as utilization of precious
materials have limited the practical generation of solar fuels. By using a solar cavity-receiver
reactor, we combined the oxygen uptake and release capacity of cerium oxide and facile catalysis
at elevated temperatures to thermochemically dissociate CO_2 and H_2O, yielding CO and H_2,
respectively. Stable and rapid generation of fuel was demonstrated over 500 cycles. Solar-to-fuel
efficiencies of 0.7 to 0.8% were achieved and shown to be largely limited by the system scale
and design rather than by chemistry.
1,257 citations
TL;DR: The presented devices are thus competitive for consumer electronics but ill-suited for on-grid electricity production in their current form.
Abstract: Upscaling of the manufacture of polymer solar cells is detailed with emphasis on cost analysis and practical approach. The device modules were prepared using both slot-die coating and screen printing the active layers in the form of stripes that were serially connected. The stripe width was varied and the resultant performance analysed. Wider stripes give access to higher geometric fill factors and lower aperture loss while they also present larger sheet resistive losses. An optimum was found through preparation of serially connected stripes having widths of 9, 13 and 18 mm with nominal geometric fill factors (excluding bus bars) of 50, 67 and 75% respectively. In addition modules with lengths of 6, 10, 20, 22.5 and 25 cm were explored. The devices were prepared by full roll-to-roll solution processing in a web width of 305 mm and roll lengths of up to 200 m. The devices were encapsulated with a barrier material in a full roll-to-roll process using standard adhesives giving the devices excellent stability during storage and operation. The total area of processed polymer solar cell was around 60 m2 per run. The solar cells were characterised using a roll-to-roll system comprising a solar simulator and an IV-curve tracer. After characterisation the solar cell modules were cut into sheets using a sheeting machine and contacted using button contacts applied by crimping. Based on this a detailed cost analysis was made showing that it is possible to prepare complete and contacted polymer solar cell modules on this scale at an area cost of 89 € m−2 and an electricity cost of 8.1 € Wp−1. The cost analysis was separated into the manufacturing cost, materials cost and also the capital investment required for setting up a complete production plant on this scale. Even though the cost in € Wp−1 is comparable to the cost for electricity using existing technologies the levelized cost of electricity (LCOE) is expected to be significantly higher than the existing technologies due to the inferior operational lifetime. The presented devices are thus competitive for consumer electronics but ill-suited for on-grid electricity production in their current form.
1,019 citations
TL;DR: A review of recent progress in this field can be found in this article by focusing on strategies that utilize visible light, such as two-step photoexcitation systems that were inspired by photosynthesis in nature, band engineering for producing novel photocatalysts that have both a high visible light absorption and suitable energy levels for water splitting, the development of new cocatalyst for efficient H 2 or O 2 production, fabrication of efficient photoelectrodes based on visible-light-responsive semiconductors, and the construction of tandem-type PEC water-splitting systems
Abstract: Photocatalytic and photoelectrochemical (PEC) water splitting using semiconductor materials has attracted considerable interest due to its potential to cleanly produce H 2 from water by utilizing abundant solar light. Since Fujishima and Honda used a TiO 2 photoanode in 1972 to split water, researchers have been attempting to develop water-splitting systems that can efficiently use visible light (which accounts for almost half of the solar spectrum on the Earth's surface) in order to realize efficient conversion of solar light. In this report, we review recent progress in this field by focusing on strategies that utilize visible light. Such strategies include two-step photoexcitation systems that were inspired by photosynthesis in nature, band engineering for producing novel photocatalysts that have both a high visible light absorption and suitable energy levels for water splitting, the development of new cocatalysts for efficient H 2 or O 2 production, fabrication of efficient photoelectrodes based on visible-light-responsive semiconductors, and the construction of tandem-type PEC water-splitting systems.
1,000 citations
TL;DR: An overview of the parabolic-trough collectors that have been built and marketed during the past century, as well as the prototypes currently under development can be found in this paper.
Abstract: This paper presents an overview of the parabolic-trough collectors that have been built and marketed during the past century, as well as the prototypes currently under development. It also presents a survey of systems which could incorporate this type of concentrating solar system to supply thermal energy up to 400 °C, especially steam power cycles for electricity generation, including examples of each application.
915 citations
843 citations
TL;DR: In this article, the authors reviewed the current state of the simulation, optimization and control technologies for the stand-alone hybrid solar-wind energy systems with battery storage, and found that continued research and development effort in this area is still needed for improving the systems' performance, establishing techniques for accurately predicting their output and reliably integrating them with other renewable or conventional power generation sources.
809 citations
TL;DR: The rapidly expanding field of polymer and organic solar cells is reviewed in the context of materials, processes and devices that significantly deviate from the standard approach which involves rigid glass substrates, indium-tinoxide electrodes, spincoated layers of conjugated polymer/fullerene mixtures and evaporated metal electrodes in a flat multilayer geometry as mentioned in this paper.
Abstract: The rapidly expanding field of polymer and organic solar cells is reviewed in the context of materials, processes and devices that significantly deviate from the standard approach which involves rigid glass substrates, indium-tin-oxide electrodes, spincoated layers of conjugated polymer/fullerene mixtures and evaporated metal electrodes in a flat multilayer geometry. It is likely that significant advances can be found by pursuing many of these novel ideas further and the purpose of this review is to highlight these reports and hopefully spark new interest in materials and methods that may be performing less than the current state-of-the-art in their present form but that may have the potential to outperform these pending a larger investment in effort.
762 citations
TL;DR: In this paper, the experimental results on solar collectors based on nanofluids made from a variety of nanoparticles (carbon nanotubes, graphite, and silver) were reported.
Abstract: Solar energy is one of the best sources of renewable energy with minimal environmental impact. Direct absorption solar collectors have been proposed for a variety of applications such as water heating; however the efficiency of these collectors is limited by the absorption properties of the working fluid, which is very poor for typical fluids used in solar collectors. It has been shown that mixing nanoparticles in a liquid (nanofluid) has a dramatic effect on the liquid thermophysical properties such as thermal conductivity. Nanoparticles also offer the potential of improving the radiative properties of liquids, leading to an increase in the efficiency of direct absorption solar collectors. Here we report on the experimental results on solar collectors based on nanofluids made from a variety of nanoparticles (carbon nanotubes, graphite, and silver). We demonstrate efficiency improvements of up to 5% in solar thermal collectors by utilizing nanofluids as the absorption mechanism. In addition the experiment...
TL;DR: In this paper, a multilayer perceptron (MLP) model was proposed to forecast the solar irradiance on a base of 24h using the present values of the mean daily solar irradiances and air temperature.
TL;DR: An overview of the physical function of organic solar cells, their state-of-the-art performance and limitations, as well as novel concepts to achieve a better material stability and higher power conversion efficiencies are presented in this paper.
Abstract: Organic solar cells have the potential to be low-cost and efficient solar energy converters, with a promising energy balance. They are made of carbon-based semiconductors, which exhibit favourable light absorption and charge generation properties, and can be manufactured by low temperature processes such as printing from solvent-based inks, which are compatible with flexible plastic substrates or even paper. In this review, we will present an overview of the physical function of organic solar cells, their state-of-the-art performance and limitations, as well as novel concepts to achieve a better material stability and higher power conversion efficiencies. We will also briefly review processing and cost in view of the market potential.
TL;DR: The impact of increasing the CT energy-in order to raise the open circuit voltage, but lowering the kinetic excess energy of the CT complexes at the same time-on the charge photogeneration will be discussed.
Abstract: Charge transfer complexes are interfacial charge pairs residing at the donor-acceptor heterointerface in organic solar cell. Experimental evidence shows that it is crucial for the photovoltaic performance, as both photocurrent and open circuit voltage directly depend on it. For charge photogeneration, charge transfer complexes represent the intermediate but essential step between exciton dissotiation and charge extraction. Recombination of free charges to the ground state is via the bound charge transfer state before being lost to the ground state. In terms of the open circuit voltage, its maximum achievable value is determined by the energy of the charge transfer state. An important question is whether or not maximum photocurrent and maximum open circuit voltage can be achieved simultaneously. The impact of increasing the CT energy-in order to raise the open circuit voltage, but lowering the kinetic excess energy of the CT complexes at the same time-on the charge photogeneration will accordingly be discussed. Clearly, the fundamental understanding of the processes involving the charge transfer state is essential for an optimisation of the performance of organic solar cells.
TL;DR: Recent progress is summarized in developing a new class of semiconducting polymers, which represents the first polymeric system to generate solar PCE greater than 7%.
Abstract: Solar cells based on the polymer−fullerene bulk heterojunction (BHJ) concept are an attractive class of low-cost solar energy harvesting devices. Because the power conversion efficiency (PCE) of these solar cells is still significantly lower than that of their inorganic counterparts, however, materials design and device engineering efforts are directed toward improving their output. A variety of factors limit the performance of BHJ solar cells, but the properties of the materials in the active layer are the primary determinant of their overall efficiency. The ideal polymer in a BHJ structure should exhibit the following set of physical properties: a broad absorption with high coefficient in the solar spectrum to efficiently harvest solar energy, a bicontinuous network with domain width within twice that of the exciton diffusion length, and high donor−acceptor interfacial area to favor exciton dissociation and efficient transport of separated charges to the respective electrodes. To facilitate exciton diss...
TL;DR: This paper reviews the present day solar thermal technologies and performance analyses of existing designs, mathematical simulation, design and fabrication of innovative designs with suggested improvements have been discussed.
Abstract: 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.
TL;DR: An overview of the physical function of organic solar cells, their state-of-the-art performance and limitations, as well as novel concepts to achieve a better material stability and higher power conversion efficiencies are presented in this paper.
Abstract: Organic solar cells have the potential to be low-cost and efficient solar energy converters, with a promising energy balance. They are made from carbon-based semiconductors, which exhibit favourable light absorption and charge generation properties, and can be manufactured by low temperature processes such as printing from solvent-based inks, which are compatible with flexible plastic substrates or even paper. In this review, we will present an overview of the physical function of organic solar cells, their state-of-the-art performance and limitations, as well as novel concepts to achieve a better material stability and higher power conversion efficiencies. We will also briefly review processing and cost in view of the market potential.
TL;DR: In this paper, the improvement of the performance of roll-to-roll processed polymer solar cell modules through miniaturization of the device outline is described, and the solar cell module was used to charge a polymer lithium ion battery through a blocking diode.
Abstract: The improvement of the performance of roll-to-roll processed polymer solar cell modules through miniaturization of the device outline is described. The devices were prepared using full roll-to-roll processing comprising flexographic printing, slot-die coating and rotary screen printing to create 5 mm wide lines of ZnO, P3HT:[60/70]PCBM, PEDOT:PSS and silver on an ITO-PET substrate. The lines were spaced by 1 mm and the devices were completed by encapsulation using roll-to-roll lamination on both sides using a pressure sensitive adhesive and a multilayered barrier material having a UV-filter with a cut-off at 390 nm, oxygen and water vapor transmission rates of respectively 0.01 cm3 m−2 bar−1 day−1 and 0.04 g m−2 day−1. The final modules comprised 16 serially connected cells. The technical yield was 89% based on the criterion that the Voc had to be larger than 7.2 V. This set of modules gave respectively a voltage, current, fill factor and power conversion efficiency of 8.47 ± 0.41 V, −23.20 ± 4.10 mA, 35.4 ± 2.8% and 1.96 ± 0.34% in the case of modules based on P3HT:[60]PCBM. A total of 1960 modules were prepared for each run and the best power conversion reached was 2.75% for devices based on P3HT:[70]PCBM. The solar cell modules were used to demonstrate the complete manufacture of a small lamp entirely using techniques of flexible electronics. The solar cell module was used to charge a polymer lithium ion battery through a blocking diode. The entire process was fully automated and demonstrates the capacity of polymer solar cells in the context of flexible and printed electronics. Finally a comparison was made between the learning curve for OPV and crystalline silicon solar cells in terms of the cost per watt peak and the cumulative watt peak. OPV as a technology was found to have a significantly steeper learning curve.
TL;DR: The present article reviews the current status of using TiO(2) nanotubes in Grätzel-type, dye-sensitized solar cells and extends the overview with the latest results and findings.
Abstract: The present article reviews the current status of using TiO2 nanotubes in Gratzel-type, dye-sensitized solar cells and extends the overview with the latest results and findings. Critical factors in tube geometry (length, diameter, top morphology), crystal structure (amorphous, anatase, rutile) as well as factors affecting dye loading or electron mobility are addressed. The highest solar cell efficiencies today for pure nanotube systems reach approximately 4% while for some mixed systems, around 7% has been reported. For both systems significant room for enhancement is anticipated and some key points and strategies for improvement are outlined.
TL;DR: It was found that the reactions taking place at the interface between the active layer and the PEDOT:PSS were the major cause of device failure in the case of these inverted devices, which are compatible with full roll-to-roll (R2R) coating and industrial manufacture.
Abstract: The spatial distribution of reaction products in multilayer polymer solar cells induced by water and oxygen atmospheres was mapped and used to elucidate the degradation patterns and failure mechani...
TL;DR: A major change in the energy economy from fossil energy carriers to renewable energy fluxes is necessary to efficiently convert renewable energy into electricity and the storage of electricity or the production of a synthetic fuel.
Abstract: Since the beginning of the twenty-first century the limitations of the fossil age with regard to the continuing growth of energy demand, the peaking mining rate of oil, the growing impact of CO2 emissions on the environment and the dependency of the economy in the industrialized world on the availability of fossil fuels became very obvious. A major change in the energy economy from fossil energy carriers to renewable energy fluxes is necessary. The main challenge is to efficiently convert renewable energy into electricity and the storage of electricity or the production of a synthetic fuel. Hydrogen is produced from water by electricity through an electrolyser. The storage of hydrogen in its molecular or atomic form is a materials challenge. Some hydrides are known to exhibit a hydrogen density comparable to oil; however, these hydrides require a sophisticated storage system. The system energy density is significantly smaller than the energy density of fossil fuels. An interesting alternative to the direct storage of hydrogen are synthetic hydrocarbons produced from hydrogen and CO2 extracted from the atmosphere. They are CO2 neutral and stored like fossil fuels. Conventional combustion engines and turbines can be used in order to convert the stored energy into work and heat.
TL;DR: A novel strategy is developed that allows for tuning of the optical absorption and charge transport properties as well as the PSC efficiency of these metallopolyynes, and it is anticipated that this class of materials could soon lead to exciting applications in next-generation PSCs and other electronic or photonic devices.
Abstract: Energy remains one of the world’s great challenges. Growing concerns about limited fossil fuel resources and the accumulation of CO2 in the atmosphere from burning those fuels have stimulated tremendous academic and industrial interest. Researchers are focusing both on developing inexpensive renewable energy resources and on improving the technologies for energy conversion. Solar energy has the capacity to meet increasing global energy needs. Harvesting energy directly from sunlight using photovoltaic technology significantly reduces atmospheric emissions, avoiding the detrimental effects of these gases on the environment. Currently inorganic semiconductors dominate the solar cell production market, but these materials require high technology production and expensive materials, making electricity produced in this manner too costly to compete with conventional sources of electricity. Researchers have successfully fabricated efficient organic-based polymer solar cells (PSCs) as a lower cost alternative. Rec...
TL;DR: This research provides a method for preparing tandem DSSCs consisting of a TiO(2)-photosensitized anode and a photosensitized p-type SC as a cathode and demonstrates that ultrafast hole injection generally occurs between the sensitizer and the SC, but the resulting charge-separated state is short-lived and recombines quickly.
Abstract: Because solar energy is the most abundant renewable energy resource, the clear connection between human activity and global warming has strengthened the interest in photovoltaic science. Dye-sensitized solar cells (DSSCs) provide a promising low-cost technology for harnessing this energy source. Until recently, much of the research surrounding DSSCs had been focused on the sensitization of n-type semiconductors, such as titanium dioxide (Gratzel cells). In an n-type dye-sensitized solar cell (n-DSSC), an electron is injected into the conduction band of an n-type semiconductor (n-SC) from the excited state of the sensitizer. Comparatively few studies have examined the sensitization of wide bandgap p-type semiconductors. In a p-type DSSC (p-DSSC), the photoexcited sensitizer is reductively quenched by hole injection into the valence band of a p-type semiconductor (p-SC). The study of p-DSSCs is important both to understand the factors that control the rate of hole photoinjection and to aid the rational desi...
TL;DR: In this article, a photon-enhanced thermionic emission (PHE) was proposed for photovoltaic cells, which combines electric as well as thermal conversion mechanisms, leading to enhanced conversion efficiencies that potentially could even exceed the theoretical limits of conventional PV cells.
Abstract: Solar-energy conversion usually takes one of two forms: the ‘quantum’ approach, which uses the large per-photon energy of solar radiation to excite electrons, as in photovoltaic cells, or the ‘thermal’ approach, which uses concentrated sunlight as a thermal-energy source to indirectly produce electricity using a heat engine. Here we present a new concept for solar electricity generation, photon-enhanced thermionic emission, which combines quantum and thermal mechanisms into a single physical process. The device is based on thermionic emission of photoexcited electrons from a semiconductor cathode at high temperature. Temperature-dependent photoemission-yield measurements from GaN show strong evidence for photon-enhanced thermionic emission, and calculated efficiencies for idealized devices can exceed the theoretical limits of single-junction photovoltaic cells. The proposed solar converter would operate at temperatures exceeding 200 °C, enabling its waste heat to be used to power a secondary thermal engine, boosting theoretical combined conversion efficiencies above 50%. The conversion of solar energy into electricity usually occurs either electrically or through thermal conversion. A new mechanism, photon-enhanced thermionic emission, which combines electric as well as thermal conversion mechanisms, is now shown to lead to enhanced conversion efficiencies that potentially could even exceed the theoretical limits of conventional photovoltaic cells.
TL;DR: The current status and future perspectives of CIGS solar cells and modules are discussed in this paper, and the current status, problems, and prospects of co-evaporation and selenization are discussed.
Abstract: The current status and future perspectives of Cu(In1−xGax)Se2 (CIGS) solar cells and modules will be discussed in this paper. The conversion efficiencies of the state of the art laboratory-scale CIGS solar cells exceeded 20%, which are comparable to those of crystalline Si solar cells. The requirements on the properties of CIGS absorbers to achieve such high efficiencies will be described. The CIGS modules are already commercially available based on two major CIGS deposition techniques such as co-evaporation and selenization. The current status, problems, and prospects of co-evaporation and selenization will also be discussed. High-efficiency flexible CIGS solar cells with efficiencies similar to those fabricated on soda–lime glass (SLG) substrates have been achieved by developing a novel Na incorporation technique. Critical issues to demonstrate high-efficiency flexible solar cells will also be discussed. Copyright © 2010 John Wiley & Sons, Ltd.
21 Jun 2010
TL;DR: In this paper, thin-film amorphous Si:H solar cells with plasmonic backreflectors showed efficient light trapping, enabling a strong reduction in semiconductor film thickness.
Abstract: Thin-film amorphous Si:H solar cells with plasmonic backreflectors show efficient light trapping, enabling a strong reduction in semiconductor film thickness. Similarly, crystalline Si solar cells covered with metal nanoparticle surface coatings shows enhanced light coupling and trapping. Article not available.
TL;DR: Compared to other methods, this paper finds that the GAs is a very efficient technique to estimate the electrical parameters of PV solar cells and modules.
01 May 2010
TL;DR: In this paper, a full description of the Western Wind and Solar Integration Study (WWSIS) and its findings is provided. But the authors do not provide a detailed analysis of the results.
Abstract: This report provides a full description of the Western Wind and Solar Integration Study (WWSIS) and its findings.
TL;DR: External quantum efficiencies are enhanced about 2.5 fold around the peak solar spectrum wavelength of 560 nm, resulting in 35% overall increase in power conversion efficiency than the ITO control device under normal unpolarized light.
Abstract: Surface plasmon enhanced photo-current and power conversion efficiency of organic solar cells using periodic Ag nanowires as transparent electrodes are reported, as compared to the device with conventional ITO electrodes. External quantum efficiencies are enhanced about 2.5 fold around the peak solar spectrum wavelength of 560 nm, resulting in 35% overall increase in power conversion efficiency than the ITO control device under normal unpolarized light.