Distributed Generation and Renewable Energy Integration into the Grid: Prerequisites, Push Factors, Practical Options, Issues and Merits
Abstract
:1. Introduction
Objectives and Methodology
2. The Concept of Distributed Generation (DG)
2.1. Considerations of the Classification of DGs
2.2. Push Factors in the Increasing Addition of DG in the Power System
2.2.1. Environmentally Motivated Factors
2.2.2. Economic Factors
2.2.3. National/Regulatory Factors
2.3. Grid Expansion through Distributed Renewables
2.4. Location and Capacity of DG on a Power Network
3. Some Practical Options Used in DG to Grid Integration
3.1. Vigorous Voltage Regulation at the Level of Substations
3.2. Modified Grid Configuration
3.3. The Use of the ‘N Minus Zero’ Regulation
3.4. Reactive Power Control
3.5. Creation of Express Feeders in the MV Network
4. Issues Resulting from DG to Grid Integration
4.1. Voltage Level Fluctuations
4.2. Effects on Power Line Losses
4.3. Variability of Wind and Solar Resources
4.4. Issues from an Economic Perspective
4.5. Transient Voltage Changes
4.6. Voltage Flickers
- is the wind farm flicker coefficient obtained through a series of wind turbine tests;
- is the network impedance phase angle;
- is the annual average wind speed;
- is the wind farm rated power;
- is the short-circuit power at the point of common coupling (PCC)
4.7. Harmonics Distortion
4.8. Grid Instability
4.9. Increase in the Fault Level and Fragile Protection System
5. Review on Case Studies
5.1. Case of South of England
5.2. Case of Greece
5.3. Case of Portugal
5.4. Case of Pakistan
5.5. Case of Maryland, USA
5.6. Case Studies of DG Being Used to Resolve Grid Turbulence
5.7. Review on Ideal Test Grid
5.8. Lessons from Successful Countries Integrating Distributed Energy Sources
5.8.1. Case of Italy
5.8.2. Case of Germany
5.8.3. Case of China
6. Merits of DG Integration into the Grid
6.1. Peak Demand Curtailment
6.2. Reduction of Power Losses in the Network
6.3. Frequency Regulation
6.4. Voltage Stabilization
6.5. Less Risk of Terrorism
6.6. Shelving of Network Upgrade
6.7. Improved Reliability and Security of Supply in the Network
6.8. Delivery of Ancillary Services
6.9. Economic Viability of DG Projects
7. Discussion and Future Perspectives
8. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Acknowledgments
Conflicts of Interest
References
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Country/Institution | Capacity of DG | Location of DG | Mode of Operation |
---|---|---|---|
Sweden | ≤1500 kW | - | - |
New Zealand | <5 MW | - | - |
Australian Energy Market Operator | ≤30 MW | - | - |
International Council on Large Electricity Systems | <100 MW | Most often coupled to the distribution network | Not managed/dispatched centrally |
Bulgarian Energy Holding Company | <10 MW | Connected to the distribution network | Not managed centrally |
Electric Power Research Institute | ≤50 MW | Most often installed near load centers or distribution and medium-voltage (MV) substations | - |
Gas Research Institute | 25 kW ≤ X ≤ 25 MW | - | - |
England and Wales Electricity Markets | <100 MW | - | Not dispatched at a central point |
Estonian Power Markets | <50 MW | Connected to the distribution network | - |
Institute of Electrical and Electronics Engineering | ≤10 MW | Connected at any point within the power grid | - |
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Iweh, C.D.; Gyamfi, S.; Tanyi, E.; Effah-Donyina, E. Distributed Generation and Renewable Energy Integration into the Grid: Prerequisites, Push Factors, Practical Options, Issues and Merits. Energies 2021, 14, 5375. https://doi.org/10.3390/en14175375
Iweh CD, Gyamfi S, Tanyi E, Effah-Donyina E. Distributed Generation and Renewable Energy Integration into the Grid: Prerequisites, Push Factors, Practical Options, Issues and Merits. Energies. 2021; 14(17):5375. https://doi.org/10.3390/en14175375
Chicago/Turabian StyleIweh, Chu Donatus, Samuel Gyamfi, Emmanuel Tanyi, and Eric Effah-Donyina. 2021. "Distributed Generation and Renewable Energy Integration into the Grid: Prerequisites, Push Factors, Practical Options, Issues and Merits" Energies 14, no. 17: 5375. https://doi.org/10.3390/en14175375