Photovoltaics International Papers

Development of fine-line crystalline silicon solar cells is a potential direction for application of high-efficiency and low-cost solar cells in the industry. Fine-line mask-free metallization offers a great potential to increase cell efficiency by reducing metal shadowing losses and surface recombination losses. At China Sunergy, three promising approaches for fine-line crystalline silicon solar cells are currently undergoing research, including processes such as laser doping selective emitter (LDSE) technology, inkjet or aerosol jet printing of metal paste and upgraded screen-printing technology. This paper presents the basic investigations of these three manufacturing technologies, singling out the technology that presents the most potential for further application.

The French Ministry for the Environment, Ecology, Sustainable Development and Sea (MEEDDM) officially published a new decree concerning photovoltaic electricity generation and feed-in tariffs (FiT) on January 12th 2010. This was followed by a second decree, published on March 16th 2010, which contained some additional information and revisions to the first. This paper outlines the effects the revisions will have on France’s solar industry and provides guidelines for future developments in the country.

Power measurements of PV reference modules can, at standard testing conditions (STC), show tolerance deviations of up to ±3%, greatly affecting the maximum power output and thereby lowering the overall energy yield of the installation. Despite some existing technical problems, there is an urgent need on the part of the photovoltaic community to achieve more accuracy in power measurements in respect to the ever-growing production volumes. Some approaches being undertaken to carry out high-quality power measurements are addressed in this paper. The deviation from an ideal simulator performance are shown and discussed for two types of simulators, with reference to the most relevant parameters: irradiance level, deviation from homogeneity, spectral mismatch and temporal stability.

Solar enterprises will each be faced with the occasional surplus or lack of solar modules in their lifetimes. In these instances, it is useful to adjust these stock levels at short notice, thus creating a spot market. Spot markets serve the short-term trade of different products, where the seller is able to permanently or temporarily offset surplus, while buyers are able to access attractive offers on surplus stocks and supplement existing supply arrangements as a last resort.

Renewable energy and, specifically, the integration of photovoltaics in residential development will play an important role in the context of global sustainability and resource conservation. Just like EPIA outlines in its Solar Europe Industry Initiative (SEII) plan (2010-2012), as distributed PV and other renewable energy technologies mature, they can provide a significant share of European electricity demand. However, as their market share grows, concerns about potential impacts on the stability and operation of the electricity grid may create barriers to their future expansion. Additionally, low-cost, high-quality integration of PV in buildings and other objects poses major development challenges. The goal of the SEII is to unlock the potential for making PV a mainstream energy source, with special attention on aspects of system integration.

On April 1st 2010, the UK government’s Department of Energy and Climate Change (DECC) officially launched its renewable energy policy. The document includes the Carbon Reduction Commitment Energy Efficiency Scheme (CRC EES), designed to improve public and private sector organizations’ energy efficiency; and the generous feed-in tariff (FiT) incentive, which pays 41.3p/kWh of solar photovoltaic energy generated. This article will look at the expectations for the UK solar photovoltaics market following the government’s policy launch. The paper will focus on the impact of the UK’s late arrival to the renewable energy market; why the FiT is so incremental for successful growth; what the expectations are for the development of the UK solar PV market as well as an investigation into whether the UK is really ready for this level of change.

The demand for equipment used to manufacture solar photovoltaic solar cells and modules has grown at an explosive rate over the past five years, and the fastest-growing segment has been for systems used to manufacture thin-film cells and modules. In 2009, demand for this type of equipment reached US$1.9 billion, up from US$0.1 billion in 2004, representing an astonishing 80% compound annual growth rate over the period. However, as with the rest of the industry, 2009 saw sales flattened and the business model change from one of rapid growth to that of sustainability. The result of this transition has been some consolidation, with several major equipment vendors strengthening their position through acquisitions. The outlook for 2010 calls for sales of thin-film production equipment to recover and continue growing at a compound annual growth rate of around 15% over the next five years (see Fig. 1).

The emitter or p-n junction is the core of crystalline silicon solar cells. The vast majority of silicon cells are produced using a simple process of high temperature diffusion of dopants into the crystal lattice. This paper takes a closer look at the characteristics of this diffusion and possible variations in the process, and asks whether this step can lead to optimal emitters or whether emitters should be made with different processes in order to obtain the highest possible efficiency.

Photovoltaic modules are designed to meet the reliability and safety requirements of national and international test standards. Qualification testing is a short-duration (typically, 60-90 days) accelerated testing protocol, and it may be considered as a minimum requirement to undertake reliability testing. The goal of qualification testing is to identify the initial short-term reliability issues in the field, while the qualification testing/certification is primarily driven by marketplace requirements. Safety testing, however, is a regulatory requirement where the modules are assessed for the prevention of electrical shock, fire hazards, and personal injury due to electrical, mechanical, and environmental stresses in the field. This paper examines recent reliability and safety studies conducted at TÜV Rheinland PTL’s solar module testing facility in Arizona.

Chemical stoichiometry along with depth profiling and metallic contamination is of considerable interest for photovoltaic thin films. Conversion efficiency can be affected for example if primary components, e.g. Cd and Te, are not present at proper ratios. Moreover, amorphous silicon can vary substantially between sources and deposition technique, and qualitative comparison of trace metallic contaminants may not be sufficient to ensure final thin-film quality. This discussion presents data from atomic emission and mass spectrometry techniques that quantitatively and accurately describe both bulk and trace elemental compositions in photovoltaic materials, various thin-film matrices, and the final thin-film cell and module.