Potential induced degradation pid refers to the phenomenon of power output losses from a solar pv module. Pid the problem and how to solve it sma solar technology. Cell modifications for preventing potentialinduced. Both of these modules are framed multicrystalline mcsi with glasspolymeric backsheet construction. Potential induced degradation of solar cells and panels ieee xplore. To allow electrical measure multicrystalline standard ptype silicon solar cells, which undergo a potential induced degradation, are investigated by different methods to reveal the cause of the degradation. Pid or potential induced degradation is a problem that occurs on many photovoltaic panels when they are exposed to a negative voltage to ground. Potentialinduced degradation in photovoltaic modules. By the end of last year, jinko had over 15,000 employees and five production sites. Described in simple terms, pid is a drop in output caused by high voltage, high humidity and high temperature environments.
The solar cells configuration has an influence on the charge carrier density of the silicon used and the chemical composition of the antiglare coating. This means that some or many of the solar panel cells will be damaged and will not be able to perform its purpose, resulting to a power loss of up to 30% and solar panels lasting only. Stack eva and glass both 10 x 10 cm, square format on solar cell, well aligned to. This paper reports an extensive analysis of the potential induced degradation pid of ntype bifacial solar cells. Highlights most industrial crystalline silicon solar cells suffer from some type of lightinduced degradation lid. The factors that can cause pid include voltage, heat and humidity and most solar modules are exposed to the combination of these factors during their working life. Potential induced degradation, as the name implies, can occur when the modules voltage.
In the existing models the pid is due to the high voltages forcing the sodium ions to diffuse from glass through encapsulate and accumulating on the surface of cell. The analysis is based on combined electrical characterization, electroluminescence and external quantum efficiency measurements, carried out on solar cells submitted to high pid stresses. Most solar power is produced using csi panels, meaning over 50% of solar capacity is at risk of pid loses. His work area comprises electrical characterization, microstructural diagnostics and elemental analyses at silicon and thin films for photovoltaic applications. Potential induced degradation, as the designation implies, occurs when the modules voltage potential and leakage current drive ion mobility within the module between the semiconductor material and other elements of the module e. The scope of this paper is to analyze experimentally the potential induced degradation pid in organic solar cells.
However, in only 2 to 3 years time, potential induced degradation happens and solar panel deficit takes place faster. Potential induced degradation pid sma solar technology. Most of the pv modules already constructed are based on p. To that end, organic solar cells are manufactured and are then undergone a series of voltagedependent degradation and timedependent voltage degradation tests. Sunpower stands behind its panels with its industryleading complete. Potential induced degradation, either reversible or not, is present in all types of csi crystalline silicon pv cells and was first described back in the 1970s 2. Underperformance is the major result of potential induced degradation pid to the solar panels that you have invested on. The method has been experimentally tested on a set of panels that. Pid happens when different components in the same system are at different voltage potentials such as the frame and the solar cell, which can allow electrical current to leak and modules to. Potential induced degradation, as the name implies, can occur when the modules voltage potential and leakage current drive ion mobility within the module between the semiconductor material and other elements of the module e. Pid is an undesirable effect on of some solar modules. Pid can significantly reduce the power output of a photovoltaic pv module within the first year of operation, with. This effect may cause power loss of up to 30 percent. Panasonic 340w solar panel 96 cell vbhn340sa17 a1 solar.
In order to clarify the degradation mechanism, numerical calculations were performed in the case of thunderstroke, based on the maxwells electromagnetic equations. Review of lightinduced degradation in crystalline silicon. Test setups are presented for simulation of the pid in the lab and the influence of cell properties on pid is demonstrated in order to reveal the cell being the precondition for the pid. Experimental analysis of the potential induced degradation.
Root cause analysis of potential induced degradation in csi solar cells energy procedia, 27, 1 6 2012 recovery bibliography high voltage stress testing hvst high voltage stress conditions are identified as a crucial degradation problem for solar cells degradation usually happens quickly months, large scale and with high. Crosssection of a backcontact solar cell with ntype passivation capped with a silicon dioxide, silicon nitride arc. Potential induced degradation can lead to a performance loss of 20 % or more, even in the first few months. Since solar energy generation is getting more and more important worldwide pv systems and solar parks are becoming larger consisting of an increasing. It is a process which occurs only a few years after installation. In gridconnected pv systems, solar panels are typically connected in series to. Apr 08, 2015 potential induced degradation on pv panels. Potentialinduced degradation pid is a potentialinduced performance degradation in crystalline photovoltaic modules, caused by socalled stray currents. Pid module regeneration with the pv offset box sma. Potential induced degradation pid is a relatively recently discovered phenomenon which can occur in solar panels although a concise understanding of what causes it is still being finalised. How to reduce potential induced degradation on solar panels. This degradation mechanism is called potential induced degradation pid9. Introduction of a novel test approach and explanation 835 in this paper, a method to test the resistance against pid on the solar cell level close to.
Introduction of a novel test approach and explanation 835 in this paper, a method to test the resistance against pid on the solarcell level close to. The potential induced degradation is one of the biggest problems for practical use of solar cell panels. Potential induced degradation happens and solar panel deficit takes place faster. What is pid and how can you reduce solar power loss. Potential induced degradation pid leads to power degradation, and reduces durability and reliability of solar modules. Depending on the technology different types of potential induced degradation pid occur. The result is more power per square meter than any commercially available solar.
This paper is focusing on potential induced degradation pid of wafer based standard ptype. Potentialinduced degradation in photovoltaic modules based. In electrical engineering, voltage is defined as the difference between electric potentials. Pid effects in a solar farm, can be responsible for losses up to 30% according to tuv, one of the recommended testing organisation. In 2007, pid was reported in a number of solar panels from evergreen solar photon 12008 and 8 2008. Chemical instability refers to light induced degradation in amorphous silicon solar cells or to the limited number of redox cycles for electrolytes in novel solar cells. Keywords solar cell, potential induced degradation, thunderstroke, leakage current 1. Potential induced degradation pid is an undesirable property of some solar. As solar asset managers since 2008, we explore in this article pid effects, causes and solutions to mitigate its effects. Nevertheless the pid effect does not occur on all or even a majority of solar. As a consequence panels are frequently exposed to high relative potentials towards ground causing high voltage stress hvs. Advanced glass and solar cell surface texturing allow for excellent performance in lowlight environments. Performance declines as solar cells experience degradation due to unavoidable circumstances like uv exposure and weather cycles. Potential induced degradation pid is often considered as the most serious degradation threat to a solar plant today.
Lg panels such as our new neon module in past pid tests via fraunhofer institute and. This work, for the first time, investigates an is based method for detecting potential induced degradation pid in csi pv panels. Introduction nowadays, solar cells are widely used to generate electricity without any environmental disturbance such as thermal or atomic power generation of electricity 1 2. Impact of potential induced degradation on solar pv module. Potential induced degradation pid tests for commercially. In this short process a thin film of silicon dioxide is deposited to increase the potential induced degradation resistance of the solar cell, what is commercially called pid free solar cells 37. Potentialinduced degradation pid has received considerable attention in recent. Standard silicon solar cells with a front side emitter may suffer from pid through massive shunting pids under high voltage stress conditions. The increased usage of transformerless inverters on u. Pid potential induced degradation is a phenomenon that negatively affects the cells of pv modules. Potential induced degradation of solar cells and panels j. Light induced degradation of solar cells made from high performance multi wafers kai petter, christian fahrland, yvonne ludwig, friederike kersten. Potential induced degradation what is potential induced degradation. The first satellites such as vanguard i required only moderate power, and the weight of the solar panels was low.
This phenomenon known as potential induced degradation pid is characterized by the progressive degradation of the performance of crystalline siliconbased. Simulation suggests origin of potential induced degradation. Letid is a form of solar cell degradation seen in the field and is. Jun 05, 2017 although crystalline solar power panels are often sold with 25 to 30year lifespan guarantees, those 30yearold modules wont be performing as well as they did on day 1. Potential induced degradation, reliability, inversion layer, solar cells, theoretical model. Tests by the german fraunhofer institute showed that solar panels which are susceptible can lose more than 30% of their rated. However, until now the degradation mechanism correlated with hvs is not covered by the standard test procedures listed in iec 61215 3. When solar panels loose efficiency, how does that happen.
Gen 5 cell is 65% larger than prior generations, delivering the most powerful cell and highestefficiency panel in residential solar. Potentialinduced degradation at interdigitated back. Pid impacts the ions of a solar cell and results in the degradation of the output of that cell. In solar modules connected in series, the same current flows through all of them, so the voltage increases with each panel in the chain. A mechanism of potential induced degradation pid delay effect by ultraviolet uv light irradiation during pid test for ptype crystalline silicon csi solar cells was proposed in this work. The cause of the harmful leakage currents, besides the structure of the solar cell. Solar inverters convert the dc power to ac power by performing the process of maximum power point tracking mppt. However, the solar cells need to be exposed to high voltage stress hvs caused by a negative potential relative to ground in order to potentially cause any relevant pid in the field within the 25 years life time of a solar panel. Pingel and others published potential induced degradation of solar cells and panels, ieee photovoltaic specialists. Potential induced degradation solar modules manufacturer. Sep 03, 2015 potential induced degradation pid is a phenomena that has only recently become a concern in the photovoltaic industry. Pid the problem and how to solve it module regeneration.
The potential induced degradation 3 4 5 is now a main theme for the improvement of the solar cell durability. Pdf potential induced degradation of solar cells and panels. Berghold, potential induced degradation of solar cells and panels, in proc. Pid was first observed for sunpower modules with rearjunction ntype solar cells. It results from the leakage of electrical current from the cell of a solar pv module to the panel frame. Potential induced degradation pid is a phenomenon which affects some pv. Besides the key parameters on cell level the paper is also presenting options on panel. The pv industry is now projected to install an additional 400 to 600 gw of pv capacity by 2020 as the underlying costs of pv energy drop by an estimated 10 percent per year. But what is a panels potential to the ground exactly. Jul 07, 2017 this can be due to a potential induced degradation pid. Potentialinduced degradation pid of photovoltaic panels. Some methods to reproduce pid phenomena were reported 2,3. In this method, 6 pv module types table 1, type a,b,c,e,f,g were tested with the number of sample n3, respectively.
Pid causes an accelerated degradation in performance which expands exponentially. High voltage stress toward partial pv modules seems to result in pid, because huge numbers of pv modules are serially interconnected in large pv systems. Recovery methods for modules affected by potential induced. On the mechanism of potentialinduced degradation in. Having first been noted by schott solar ag in 2012, light and elevated temperature induced degradation letid has been shown to cause severe degradation in multicrystalline mcsi silicon cells, especially those using cell passivation technology, e. Potential induced degradation pid is a phenomena that has only recently become a concern in the photovoltaic industry. Jinko solar was founded in 2006 as a wafer manufacturer, had their ipo in 2010 and then vertically integrated the company by manufacturing cells and modules as well. As it causes large output power decrease in short term, potential induced degradation pid inflicts large loss on users 1. Potential induced degradation pid is characterized by the power loss of solar modules under high voltage stress across the module layer stack between framingglass surface and solar cells. Understanding potential induced degradation padcon.
Designed to deliver 60% more energy over 25 years in. Jan 23, 2017 what is potential induced degradation. High voltage stress toward partial pv modules seems to result in pid, because huge numbers of pv modules are serially interconnected in. Ideally, the solar panels are expected to last and display its optimum performance for 20 years. Solar cells with hotspots can heat up to such a high temperature that parts of a module burn out. The high electric potential difference between the encapsulated solar cells and the outer module construction leads to leakage currents with the result of extensive microscopic shunting of the solar cells. Besides the precondition of having a pid sensitive cell they also showed ways to stop or minimize pid on panel.
Potential differences between in a string connected pvcells and the ground potential cause a leakage current as early as 1978 and in the nineties leakage current driven electrochemical corrosion and polarization effects of crystalline and thinfilm cells in modules were reported, and a minimum. Potential induced degradation of solar cells and panels. Reliability was ensured by protecting the cells with a quartz or sapphire cover sheet from energetic particles outside the atmosphere and by using np type cells on 6. Long weather resistance excellent antipid potential induced degradation certified in fireproofing for safety superior quality control iso 9001. Solar panel efficiency can be calculated by mpp maximum power point value of solar panels. Eu pvsec proceedings potential induced degradation of solar. Potential induced degradation pid can be understood as a designation for aging effects which arise due to. Effect of parameters on potential induced degradation of. For help with string inverters, 3tl, refusol, or pv powered residential units. This paper is focusing on potential induced degradation pid of wafer based standard ptype silicon technology once exposed to external potentials in the field.
In the rank order of impact, these failures are potential induced degradation, failure of bypass diodes, cell cracks, and discolouration of the encapsulant or pottant material. This potential degradation mechanism is not monitored by the typical pv tests listed in iec 61215 2. Potential induced degradation pid may cause significant performance losses of solar power plants. Concept behind pid potential induced degradation in solar panels. Advanced energy inverter products have been discontinued, but we continue to offer ae oem product service and support. Sunpower performance panels are the most deployed shingled solar panel in the world. For commercial modules incorporating ptype cells, it has been established that local shunts in the cell are responsible for the degradation. What is pid potential induced dagradation explained. The effect of hvs on long term stability of solar panels depending on the leakage current between solar cells and ground has been first addressed by nrel in 2005 1. The term potential induced degradation was first used in the 2010 publication by module manufacturer solon, which examined the phenomenon in detail. A particular focus of his work is on assessment and physical understanding of potential induced degradation of silicon solar cells. Hit ntype cells result in extremely low light induced degradation lid and zero potential induced degradation pid which supports reliability and longevity. Potentialinduced degradation pid of csi solar cells. Potential induced degradation power degradation due the exposure to an external potential external potential potential relative to ground high voltage stress power degradation caused by the exposure to a potential relative to ground, and dependent on its magnitude and sign two cases.