An Investigation into the Potential of Hosting Capacity and the Frequency Stability of a Regional Grid with Increasing Penetration Level of Large-Scale PV Systems

It is widely believed that the incorporation of renewable energy to the current power grid is the way forward in achieving sustainable power generation. Currently, with the reduction of PV prices, many countries have started connecting PV systems into their grid network, hence leading to a sharp increase of the penetration levels of renewable electricity production. This will bring significant change in the load pattern and the ramping requirements of the grid’s conventional generation system due to the varying nature of the renewable energy generation. This significant change affects the stability of the grid frequency because it becomes more challenging for the system operators to maintain the equilibrium between the generation and load. Additionally, this significant change affects the PV system potential hosting capacity of the traditional grid because of the PV system’s curtailment in order to comply with the constraints of the grid’s conventional generation system. In this paper, the net load, grid frequency stability, and grid potential hosting capacity are evaluated in the situation of increasing the penetration level of large-scale PV systems generation into the grid. The results show that the grid operators will face increasingly variable net load patterns and steeper ramping events as the PV system penetration level increases. Additionally, the results show the requirement of having flexibility measures that target each grid constraint as the PV system penetration level increases.

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The Effect of Plants on the Energy Output of Green Roof Photovoltaic Systems in Tropical Climates

Sustainability ◽

10.3390/su13084505 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4505

Author(s):

Chila Kaewpraek ◽

Liaqat Ali ◽

Md. Arfeen Rahman ◽

Mohammad Shakeri ◽

M. S. Chowdhury ◽

...

Keyword(s):

Renewable Energy ◽

Solar Energy ◽

Production Efficiency ◽

Renewable Energy Sources ◽

Green Roof ◽

Electricity Production ◽

Energy Output ◽

Pv System ◽

Pv Systems ◽

The Future

The rapid rise in the number of fossil fuel uses over the last few decades has increased carbon dioxide (CO2) emissions. The purpose of implementing renewable energy solutions, such as solar, hydro, wind, biomass, and other renewable energy sources, is to mitigate global climate change worldwide. Solar energy has received more attention over the last few decades as an alternative source of energy, and it can play an essential role in the future of the energy industry. This is especially true of energy solutions that reduce land use, such as off-grid and on-grid solar rooftop technologies. This study aims to evaluate the energy conversion efficiency of photovoltaic (PV) systems in tropical environments. It also explores the effect of growing plants beneath PV panels. Two identical grid-connected PV systems—each containing five solar panels—were installed. The overall power production of each PV system was about 1.4 kWp. All the collected data were processed and analysed in the same way and by the same method. The PV systems were installed in two different environments—one with the possibility of growing the plants beneath the PV panels (PViGR module) and one with no possibility of growing the plants beneath the PV panels (PViSR module). The experiments were conducted in the Bo Yang District of Songkhla, Thailand over a 12-month period. Our findings indicate that green roof photovoltaic (GRPV) systems can produce around 2100 kWh of electricity in comparison to the 2000 kWh produced by other solar energy systems. Thereby, growing plants beneath PV panels increases electricity production efficiency by around 2%. This difference comes from the growing of plants underneath GRPV systems. Plants do not only help to trap humidity underneath GRPV systems but also help to cool the PV panels by absorbing the temperature beneath GRPV systems. Thus, in the production of electrical energy; the system was clearly showing significant differences in the mentioned results of both PV solar systems, which are evident for great energy efficiency performances in the future.

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Economic Viability of Renewable Energy Communities under the Framework of the Renewable Energy Directive Transposed to Austrian Law

Energies ◽

10.3390/en13215743 ◽

2020 ◽

Vol 13 (21) ◽

pp. 5743 ◽

Cited By ~ 2

Author(s):

Bernadette Fina ◽

Hans Auer

Keyword(s):

Renewable Energy ◽

Large Scale ◽

Cost Savings ◽

Economic Viability ◽

Pv System ◽

Pv Systems ◽

Energy Community ◽

Additional Support ◽

Electricity Transfer ◽

Austrian Law

This study is concerned with the national transposition of the European Renewable Energy Directive into Austrian law. The objective is to estimate the economic viability for residential customers when participating in a renewable energy community (REC), focused on PV electricity sharing. The developed simulation model considers the omission of certain electricity levies as well as the obligatory proximity constraint being linked to grid levels, thus introducing a stepwise reduction of per-unit grid charges as an incentive to keep the inner-community electricity transfer as local as possible. Results show that cost savings in residential RECs cover a broad range from 9 EUR/yr to 172 EUR/yr. The lowest savings are gained by customers without in-house PV systems, while owners of a private PV system make the most profits due to the possibility of selling as well as buying electricity within the borders of the REC. Generally, cost savings increase when the source is closer to the sink, as well as when more renewable electricity is available for inner-community electricity transfer. The presence of a commercial customer impacts savings for households insignificantly, but increases local self-consumption approximately by 10%. Despite the margin for residential participants to break even being narrow, energy community operators will have to raise a certain participation fee. Such participation fee would need to be as low as 2.5 EUR/month for customers without in-house PV systems in a purely residential REC, while other customers could still achieve a break-even when paying 5 EUR/month to 6.7 EUR/month in addition. Those results should alert policy makers to find additional support mechanisms to enhance customers’ motivations to participate if RECs are meant as a concept that should be adopted on a large scale.

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Influence of Parasitic Parameters on DC–DC Converters and Their Method of Suppression in High Frequency Link 35 kV PV Systems

Energies ◽

10.3390/en12193743 ◽

2019 ◽

Vol 12 (19) ◽

pp. 3743

Author(s):

Rui Li ◽

Fangyuan Shi ◽

Xu Cai ◽

Haibo Xu

Keyword(s):

High Frequency ◽

Large Scale ◽

Pv System ◽

Zero Voltage Switching ◽

Pv Systems ◽

Magnetic Inductance ◽

Parasitic Parameters ◽

Saturable Inductor ◽

Secondary Side ◽

Pv Power Generation

Photovoltaic (PV) power generation has shown a trend towards large-scale medium- or high-voltage integration in recent years. The development of high-frequency link PV systems is necessary for the further improvement of system efficiency and the reduction of system cost. In the system, high-frequency high-step-up ratio LLC converters are one of the most important parts. However, the parasitic parameters of devices lead to a loss of zero-voltage switching (ZVS) in the LLC converter, greatly reducing the efficiency of the system, especially in such a high-frequency application. In this paper, a high-frequency link 35 kV PV system is presented. To suppress the influences of parasitic parameters in the LLC converter in the 35 kV PV system, the influence of parasitic parameters on ZVS is analyzed and expounded. Then, a suppression method is proposed to promote the realization of ZVS. This method adds a saturable inductor on the secondary side to achieve ZVS. The saturable inductor can effectively prevent the parasitic elements of the secondary side from participating in the resonance of the primary side. The experimental results show that this method achieves a higher efficiency than the traditional method by reducing the magnetic inductance.

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Optimum Renewable Fraction for Grid-connected Photovoltaic in Office Building Energy Systems in Indonesia

International Journal of Power Electronics and Drive Systems (IJPEDS) ◽

10.11591/ijpeds.v9.i4.pp1866-1874 ◽

2018 ◽

Vol 9 (4) ◽

pp. 1866 ◽

Cited By ~ 1

Author(s):

Ayong Hiendro ◽

Ismail Yusuf ◽

F. Trias Pontia Wigyarianto ◽

Kho Hie Khwee ◽

Junaidi Junaidi

Keyword(s):

Carbon Dioxide ◽

Renewable Energy ◽

Energy Systems ◽

Building Energy ◽

Office Building ◽

Pv System ◽

Optimum Result ◽

Pv Systems ◽

Building Energy Systems

This paper analyzes influences of renewable fraction on grid-connected photovoltaic (PV) for office building energy systems. The fraction of renewable energy has important contributions on sizing the grid-connected PV systems and selling and buying electricity, and hence reducing net present cost (NPC) and carbon dioxide (CO2) emission. An optimum result with the lowest total NPC for serving an office building is achieved by employing the renewable fraction of 58%, in which 58% of electricity is supplied from the PV and the remaining 42% of electricity is purchased from the grid. The results have shown that the optimum grid-connected PV system with an appropriate renewable fraction value could greatly reduce the total NPC and CO2 emission.

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The Siren Song of Renewable Energy

Why We Need Nuclear Power ◽

10.1093/oso/9780199344574.003.0009 ◽

2014 ◽

Author(s):

Michael H. Fox

Keyword(s):

Renewable Energy ◽

Nuclear Power ◽

Fossil Fuels ◽

Rocky Mountain ◽

Electricity Production ◽

The Sun ◽

Solar Panels ◽

Water Heater ◽

Pv System ◽

Energy Needs

Renewable energy from the sun—which includes solar, wind, and water energy— can meet all of our energy needs and will allow us to eliminate our dependence on fossil fuels for electricity production. At least, that is the “Siren song” that seduces many people. Amory Lovins, the head of the Rocky Mountain Institute, has been one of the strongest proponents of getting all of our energy from renewable sources (what he calls “soft energy paths”) (1) and one of the most vociferous opponents of nuclear power. A recent article in Scientific American proposes that the entire world’s needs for power can be supplied by wind, solar, and water (2). Is this truly the nirvana of unlimited and pollution-free energy? Can we have our cake and eat it, too? Let’s take a critical look at the issues surrounding solar and wind power. Let me be clear that I am a proponent of solar energy. I built a mountain cabin a few years ago that is entirely off the grid. All of the electricity comes from solar photovoltaic (PV) panels with battery storage. The 24 volt DC is converted to AC with an inverter and is fed into a conventional electrical panel. It provides enough energy to power the lights, run a 240 volt, three-quarter horsepower water pump 320 feet deep in the well, and electrical appliances such as a coffee pot, toaster, and vacuum cleaner. But I am not implying that all of my energy needs come from solar. The big energy hogs—kitchen range, hot water heater, and a stove in the bedroom—are all powered with propane. Solar is not adequate to power these appliances. In 2010 I also had a 2.5 kW solar PV system installed on my house that ties into the utility grid. When the sun is shining, I use the electricity from the solar panels, and if I use less than I generate, it goes out on the grid to other users. If it does not produce enough for my needs, then I buy electricity from the grid.

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Large Photovoltaic Power Plants Integration: A Review of Challenges and Solutions

Energies ◽

10.3390/en12193798 ◽

2019 ◽

Vol 12 (19) ◽

pp. 3798 ◽

Cited By ~ 9

Author(s):

Mansouri ◽

Lashab ◽

Sera ◽

Guerrero ◽

Cherif

Keyword(s):

System Integration ◽

Power Plants ◽

Large Scale ◽

System Stability ◽

Pv System ◽

Pv Systems ◽

Large Scale Integration ◽

Voltage Limit ◽

The Stability ◽

Scale Integration

Renewable energy systems (RESs), such as photovoltaic (PV) systems, are providing increasingly larger shares of power generation. PV systems are the fastest growing generation technology today with almost ~30% increase since 2015 reaching 509.3 GWp worldwide capacity by the end of 2018 and predicted to reach 1000 GWp by 2022. Due to the fluctuating and intermittent nature of PV systems, their large-scale integration into the grid poses momentous challenges. This paper provides a review of the technical challenges, such as frequency disturbances and voltage limit violation, related to the stability issues due to the large-scale and intensive PV system penetration into the power network. Possible solutions that mitigate the effect of large-scale PV system integration on the grid are also reviewed. Finally, power system stability when faults occur are outlined as well as their respective achievable solutions.

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Renewable Energy System on Frequency Stability Control Strategy Using Virtual Synchronous Generator

Symmetry ◽

10.3390/sym12101697 ◽

2020 ◽

Vol 12 (10) ◽

pp. 1697 ◽

Cited By ~ 1

Author(s):

Lingling Li ◽

Hengyi Li ◽

Ming-Lang Tseng ◽

Huan Feng ◽

Anthony S. F. Chiu

Keyword(s):

Renewable Energy ◽

Power System ◽

Large Scale ◽

Synchronous Generator ◽

Frequency Stability ◽

Stability Control ◽

System Stability ◽

Generator System ◽

System Frequency ◽

Virtual Synchronous Generator

This study constructs a novel virtual synchronous generator system based on a transfer function, and optimizes the parameters of the model by using the improved whale algorithm to improve the frequency control ability of virtual synchronous generator. Virtual synchronous generator technology helps to solve the problem that the integration of large-scale renewable energy generation into the power system leads to the deterioration of system frequency stability. It can maintain the symmetry of grid-connected scale and system stability. The virtual synchronous generator technology makes the inverter to have the inertia and damping characteristics of a synchronous generator. The inverter has the inertia characteristics and damps to reduce the frequency instability of high penetration renewable energy power system. The improved whale algorithm is efficient to find the best combination of control parameters and the effectiveness of the algorithm is verified by microgrid and power system. The results show that the proposed frequency coordination control scheme suppresses the frequency deviation of power system and keep the system frequency in a reasonable range.

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The Technical Challenges Facing the Integration of Small-Scale and Large-scale PV Systems into the Grid: A Critical Review

Electronics ◽

10.3390/electronics8121443 ◽

2019 ◽

Vol 8 (12) ◽

pp. 1443 ◽

Cited By ~ 3

Author(s):

Abdullah Alshahrani ◽

Siddig Omer ◽

Yuehong Su ◽

Elamin Mohamed ◽

Saleh Alotaibi

Keyword(s):

Large Scale ◽

Distribution Network ◽

Small Scale ◽

Energy Access ◽

Solar Pv ◽

Pv System ◽

Pv Systems ◽

Technical Challenges ◽

Technical Solutions ◽

The Impact

Decarbonisation, energy security and expanding energy access are the main driving forces behind the worldwide increasing attention in renewable energy. This paper focuses on the solar photovoltaic (PV) technology because, currently, it has the most attention in the energy sector due to the sharp drop in the solar PV system cost, which was one of the main barriers of PV large-scale deployment. Firstly, this paper extensively reviews the technical challenges, potential technical solutions and the research carried out in integrating high shares of small-scale PV systems into the distribution network of the grid in order to give a clearer picture of the impact since most of the PV systems installations were at small scales and connected into the distribution network. The paper reviews the localised technical challenges, grid stability challenges and technical solutions on integrating large-scale PV systems into the transmission network of the grid. In addition, the current practices for managing the variability of large-scale PV systems by the grid operators are discussed. Finally, this paper concludes by summarising the critical technical aspects facing the integration of the PV system depending on their size into the grid, in which it provides a strong point of reference and a useful framework for the researchers planning to exploit this field further on.

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Cost-Benefit Analysis of Small-Scale Rooftop PV Systems: The Case of Dragotin, Croatia

Applied Sciences ◽

10.3390/app11199318 ◽

2021 ◽

Vol 11 (19) ◽

pp. 9318

Author(s):

Mladen Bošnjaković ◽

Ante Čikić ◽

Boris Zlatunić

Keyword(s):

Renewable Energy Sources ◽

Electricity Consumption ◽

Electricity Production ◽

Small Scale ◽

Optimal Size ◽

Pv System ◽

Load Curve ◽

Pv Systems ◽

Hourly Data ◽

Daily Load

A large drop in prices of photovoltaic (PV) equipment, an increase in electricity prices, and increasing environmental pressure to use renewable energy sources that pollute the environment significantly less than the use of fossil fuels have led to a large increase in installed roof PV capacity in many parts of the world. In this context, this paper aims to analyze the cost-effectiveness of installing PV systems in the rural continental part of Croatia on existing family houses. A typical example is a house in Dragotin, Croatia with an annual consumption of 4211.70 kWh of electricity on which PV panels are placed facing south under the optimal slope. The calculation of the optimal size of a PV power plant with a capacity of 3.6 kW, without battery energy storage, was performed by the Homer program. The daily load curve was obtained by measuring the electricity consumption at the facility every hour during a characteristic day in the month of June. As most of the activities are related to electricity consumption, repeating during most days of the year, and taking into account seasonal activities, daily load curves were made for a characteristic day in each month of the year. Taking into account the insolation for the specified location, using the Internet platform Solargis Prospect, hourly data on the electricity production of selected PV modules for a characteristic day in each month were obtained. Based on the previous data, the electricity injected into the grid and taken from the grid was calculated. Taking into account the current tariffs for the sale and purchase of electricity, investment prices, and maintenance of equipment, the analysis shows that such a PV system can pay off in 10.5 years without government incentives.

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An Assessment Framework for PV Parallel MPPT Configuration with a New Utilization for UIPS Loads

WSEAS TRANSACTIONS ON POWER SYSTEMS ◽

10.37394/232016.2022.17.2 ◽

2022 ◽

Vol 17 ◽

pp. 9-20

Author(s):

Mostafa El-Sayed ◽

Ahmed Huzayyin ◽

Abdelmomen Mahgoub ◽

Essam Abulzahab

Keyword(s):

Input Power ◽

Point Of View ◽

Assessment Procedure ◽

Generation System ◽

Pv System ◽

Remote Areas ◽

Pv Systems ◽

Series Configuration ◽

Power Generation System ◽

Efficiency And Reliability

The prevalence rate of photovoltaics (PV)-based generation systems has increased by more than 15 folds in the last decade, putting it on the top compared to any other power generation system from the expandability point of view. A portion of this huge expansion serves to energize standalone remote areas. Seeking improvements from different aspects of PV systems has been the focus of many studies. In the track of these improvements, parallel MPPT configuration for PV standalone systems have been introduced in the literature as an alternative to a series configuration to improve the overall efficiency of standalone PV systems. However, this efficiency improvement of the parallel MPPT configuration over the series one is not valid for any standalone application, therefore an assessment procedure is required to determine the most efficient MPPT configuration for different standalone applications. Therefore, in this study, an assessment procedure of parallel MPPT is conducted to demonstrate the suitability of utilizing such a configuration compared to series one, based on load daytime energy contributions. This assessment will help PV system designers to determine which MPPT configuration should be selected for applications under study. Furthermore, a new utilization of parallel MPPT configuration is introduced for operating universal input power supply (UIPS) loads to eliminate the inverter stage, thereby increasing the overall system efficiency and reliability. Finally, a systematic procedure to size the complete system is introduced and reinforced by a sizing example.

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