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As the renewable penetration in the grid increases, the grid-takes-all-renewable paradigm will no longer be sustainable. We consider a day-ahead (DA) electricity market composed of a renewable generator, a natural gas power plant (NGPP) and a coal power plant (CPP). Each player provides the Independent System Operator (ISO) with their commitment and their asking price. The ISO schedules the generators using a least-cost strategy. Because of the intrinsic uncertainty of the renewable generation, the renewable player might be unable to meet its DA commitment. In the event of a shortfall, the renewable generator incurs a penalty so that the non-renewable sources are not forced to consume the cost of renewable intermittence. It has been recognized that such a penalty can lead to conservative bidding by the renewable generator, which may lead to lower than desired penetration of renewable energy in the grid. We formulate and analyze a contract between the renewable producer and the NGPP so that the NGPP reserves some amount of natural gas to hedge the renewable producer against shortfalls. Expressions for the optimal commitments of the players and for the optimal reserve contract are derived. When a reserve contract is established, we observe an increase both in the average profit of the players involved and in the renewable participation in the market. Thus, we show that a Pareto-optimal contract between market players can improve renewable penetration.
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Review of Control Techniques for Wind Energy Systems
In recent years, penetration of renewable energy resources into the power grid has increased significantly. Wind, as a renewable, clean, and abundantly available source of energy, has an important share in the energy mix. However, increasing the penetration of wind power in the power grid can adversely affect the power quality and introduce new operational challenges. This paper discusses issues related to the integration of wind farms in the power system, such as maximum power point tracking, fault ride-through capabilities, interarea and subsynchronous oscillations, and voltage flicker, and provides a review of the existing control strategies to address these issues in Types I, II, III, and IV wind turbines. This paper also identifies challenges and opportunities ahead.
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- PAR ID:
- 10282658
- Date Published:
- Journal Name:
- Energies
- Volume:
- 13
- Issue:
- 24
- ISSN:
- 1996-1073
- Page Range / eLocation ID:
- 6666
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/en13246666
