Space Station Freedom solar array panels plasma interaction test facility

The Space Station Freedom Power System will make extensive use of photovoltaic (PV) power generation. The phase 1 power system consists of two PV power modules each capable of delivering 37.5 KW of conditioned power to the user. Each PV module consists of two solar arrays. Each solar array is made up of two solar blankets. Each solar blanket contains 82 PV panels. The PV power modules provide a 160 V nominal operating voltage. Previous research has shown that there are electrical interactions between a plasma environment and a photovoltaic power source. The interactions take two forms: parasitic current loss (occurs when the currect produced by the PV panel leaves at a high potential point and travels through the plasma to a lower potential point, effectively shorting that portion of the PV panel); and arcing (occurs when the PV panel electrically discharges into the plasma). The PV solar array panel plasma interaction test was conceived to evaluate the effects of these interactions on the Space Station Freedom type PV panels as well as to conduct further research. The test article consists of two active solar array panels in series. Each panel consists of two hundred 8 cm x 8 cm silicon solar cells. The test requirements dictated specifications in the following areas: plasma environment/plasma sheath; outgassing; thermal requirements; solar simulation; and data collection requirements

Modeling and Simulation of Solar Photovoltaic Cell for the Generation of Electricity in UAE

This paper proposes the implementation of a circuit based simulation for a Solar Photovoltaic (PV) cell in order to get the maximum power output. The model is established based on the mathematical model of the PV module. As the PV cell is used to determine the physical and electrical behavior of the cell corresponding to environmental factors such as temperature and solar irradiance, this paper evaluates thirty years solar irradiation data in United Arab Emirates (UAE), also analyzes the performance parameters of PV cell for several locations. Based on the Shockley diode equation, a solar PV module is presented. However, to analyze the performance parameters, Solarex MSX 120, a typical 120W module is selected. The mathematical model for the chosen module is executed in Matlab. The consequence of this paper reflects the effects of variation of solar irradiation on PV cell within UAE. Conclusively, this paper determines the convenient places for implementing the large scale solar PV modules within UAE.Comment: To be published in 5th International Conference on Advances in Electrical Engineering (ICAEE-2019

Case study 2. Model validation using existing data from PV generation on selected New Zealand schools

Solar energy is abundant, free and non-polluting. Solar energy can offset the consumption of fossil fuels, greenhouse gas emission reduction targets and contribute to meeting the fast-growing energy demands. The use of solar energy for electricity generation from photovoltaic (PV) panels has increased but is still not a widely utilised technology in New Zealand. This research approximated the potential solar energy that could be harvested from the rooftops of existing residential buildings in a case study city. This research is divided into two work strands, each involving a case study. The first strand investigated if a model could be developed, using existing data sources to determine the solar harvesting potential from the rooftops of existing residential buildings. The second strand involved the validation of the solar PV prediction model proposed in the first strand of the research, to test the reliability of the modelling outcomes. Invercargill City was selected as the study city for case study 1. Invercargill is the southernmost city in New Zealand so represents a worst case scenario. The method involved merging computer-simulation of solar energy produced from PV modelling and mapping incoming solar radiation data from north facing residential rooftop area. The work utilised New Zealand statistical census map of population and dwelling data, as well as digital aerial map to quantify the efficient roof surface area available for PV installations. The solar PV potential was calculated using existing formulas to investigate the contribution of roof area to the solar PV potential in buildings using roof area and population relationship. The estimated solar PV potential was 82,947,315 kWh per year generated from the total solar efficient roof surface area of 740,504 m². This equates to approximately 60.8% of the residential electricity used in Invercargill’s urban area, based on the 7,700 kWh typical annual electricity consumptions per household. The result represents an immense opportunity to harvest sustainable energy from Invercargill’s residential rooftops. To verify the accuracy of the developed method for predicting the PV outputs, the model was applied to actual generation data from grid-connected solar photovoltaic (PV) systems that are installed in New Zealand schools under the Schoolgen programme (Case Study 2). A total of 66 Schoolgen PV rooftop models were incorporated in the analysis. At this stage, the actual system parameters including size, panel type and efficiency were included in the analysis. The performance prediction and analysis outcome showed the parameters and operating conditions that affect the amount of energy generated by the PV systems. This part of the research showed the area where the PV model can be improved. The predicted generation from the model was found to be lower than the actual generation data. Schoolgen systems operating at over 0.75 performance ratio were found to be underestimated. This indicated that most Schoolgen PV systems were operating at higher capacities than predicted by the default value of system losses. The analysis demonstrated the effects of PV technology type, site orientation, direction and tilted angle of the panels on the ability to generate expected amount of potential capacity based on solar resource availability in different site scenarios. This in turn has provided more in depth analysis of the research and served to expand the area for improvements in the design of the model

Solar PV rural electrification and energy-poverty: A review and conceptual framework with reference to Ghana

In spite of the intention of governments to increase the use of renewable energy in electricity supply, particularly the use of solar photovoltaic (PV) for energy poverty reduction in rural and peri-urban areas of Africa, there is relatively little information on how solar PV electrification impacts on energy poverty reduction. Therefore, there is a gap in the literature and hence the need for continuous research. Using Ghana as a reference country, the historical trend, donor cooperation and other aspects of solar PV rural electrification are discussed . The paper illustrates the intersectoral linkages of solar PV electrification and indicators on education, health, information acquisition, agriculture and micro-enterprises. It also reviews sustainability related issues including costs and market barriers, subsidies, stakeholders involvement, political and policy implications, which are critical factors for sustainable market development of solar PV and other renewables. Finally, a common framework is developed to provide a basic understanding of how solar PV electrification impacts on energy-poverty. This framework provides a structure of the interrelated concepts and principles relevant to the issues under review.Rural electrification; solar PV electrification; energy-poverty; renewable energy; economic development; Ghana; Africa

An improved optimization technique for estimation of solar photovoltaic parameters

The nonlinear current vs voltage (I-V) characteristics of solar PV make its modelling difficult. Optimization techniques are the best tool for identifying the parameters of nonlinear models. Even though, there are different optimization techniques used for parameter estimation of solar PV, still the best optimized results are not achieved to date. In this paper, Wind Driven Optimization (WDO) technique is proposed as the new method for identifying the parameters of solar PV. The accuracy and convergence time of the proposed method is compared with results of Pattern Search (PS), Genetic Algorithm (GA), and Simulated Annealing (SA) for single diode and double diode models of solar PV. Furthermore, for performance validation, the parameters obtained through WDO are compared with hybrid Bee Pollinator Flower Pollination Algorithm (BPFPA), Flower Pollination Algorithm (FPA), Generalized Oppositional Teaching Learning Based Optimization (GOTLBO), Artificial Bee Swarm Optimization (ABSO), and Harmony Search (HS). The obtained results clearly reveal that WDO algorithm can provide accurate optimized values with less number of iterations at different environmental conditions. Therefore, the WDO can be recommended as the best optimization algorithm for parameter estimation of solar PV

A hierarchical architecture for increasing efficiency of large photovoltaic plants under non-homogeneous solar irradiation

Under non-homogeneous solar irradiation, photovoltaic (PV) panels receive different solar irradiance, resulting in a decrease in efficiency of the PV generation system. There are a few technical options to fix this issue that goes under the name of mismatch. One of these is the reconfiguration of the PV generation system, namely changing the connections of the PV panels from the initial configuration to the optimal one. Such technique has been widely considered for small systems, due to the excessive number of required switches. In this paper, the authors propose a new method for increasing the efficiency of large PV systems under non-homogeneous solar irradiation using Series-Parallel (SP) topology. In the first part of the paper, the authors propose a method containing two key points: a switching matrix to change the connection of PV panels based on SP topology and the proof that the SP-based reconfiguration method can increase the efficiency of the photovoltaic system up to 50%. In the second part, the authors propose the extension of the method proposed in the first part to improve the efficiency of large solar generation systems by means of a two-levels architecture to minimize the cost of fabrication of the switching matrix

Equal, equitable, or optimal : a comparative analysis of the regional policies and financial structures impacting residential solar adoption

Diversification of energy production is increasingly important as concerns over emissions, energy independence and fuel costs emerge. As such, policies and incentive structures have been put in place by both federal and local government to increase solar energy generation. Since solar energy generation is not confined to utility or commercial scale projects it is feasible for households to become small generators and for local utilities to encourage or discourage residential energy production. While the cost of solar has been decreasing, installing residential solar PV is still a capital-intensive venture. The impact of residential solar has been debated but the presence of federal tax credits, increasing renewable energy requirements, and reduced emission standards signify that it is a subject cities and utilities must contend with. The Texas cities of Austin, San Antonio, and Georgetown represent three case studies of different programs, policies and financial approaches towards residential solar PV. The findings suggest that most average 20-year residential solar PV projects are net positive for homeowners. 10-year projects in cities that offer up-front rebates, such as Austin and San Antonio, are more likely to save residents money on the investment over non-rebate cities like Georgetown. 10-year projects without the federal investment tax credit result in mostly net negative financial outcomes for residents. Each city has utilized a unique a model that can be classified as equal, equitable, or optimal. These models have varying impacts on residents, including consumer reasoning for installing solar and financial feasibility of the investment. Austin and San Antonio have stated goals of increasing renewable energy generation and include residential solar PV in the renewable expansion, because of this, the cities provide more assistance and programs for residents to participate in solar projects. Georgetown already has power purchase agreements in place to fully provide renewable energy to residents and as such are not as interested in incentivizing residential solar PV for the environmental effects.Energy and Earth ResourcesBusiness Administratio

'Market penetration and pay-back period analysis of a solar photovoltaic system under Indian conditions'

The use of pay-back period analysis for economic evaluation of solar photovoltaic (PV) system reinforces the importance of the duration of the system. In a dynamic economic environment, the cost of energy increases at a faster rate than the common inflation rate. A time can be ascertained at which the market entry of the PV system will be profitable, i.e. at which the pay-back time drops below a value considered as the market threshold, provided the parameters describing the dynamic economic system remain unchanged. The market penetration of the PV system has been determined in Indian economic conditions and found to depend mainly on PV array costs and energy income reinvestment rate. The low PV array cost, high-energy income reinvestment rate, high solar cell reference efficiency and high battery efficiency have a substantial effect on the reduction of the energy price and pay-back period with early market penetration by the PV system. Keywords: photovoltaic (PV) system; pay-back period; market penetration; renewable energy economics.renewable energy economics, pay-back period, market penetration, solar photovoltaic (PV) system.

Efficiency of Photovoltaic Systems in Mountainous Areas

Photovoltaic (PV) systems have received much attention in recent years due to their ability of efficiently converting solar power into electricity, which offers important benefits to the environment. PV systems in regions with high solar irradiation can produce a higher output but the temperature affects their performance. This paper presents a study on the effect of cold climate at high altitude on the PV system output. We report a comparative case study, which presents measurement results at two distinct sites, one at a height of 612 meters and another one at a mountain site at a height of 1764 meters. This case study applies the maximum power point tracking (MPPT) technique in order to determine maximum power from the PV panel at different azimuth and altitude angles. We used an Arduino system to measure and display the attributes of the PV system. The measurement results indicate an increased efficiency of 42% for PV systems at higher altitude