(SEM VII) THEORY EXAMINATION 2024-25 DEREGULATED POWER SYSTEM

SECTION A

(2 × 10 = 20 Marks)

a) Define deregulation in the context of power systems

Deregulation in power systems refers to the restructuring of the electricity industry by reducing government control and allowing competition among power producers and suppliers. It separates generation, transmission, and distribution functions to promote efficiency, transparency, and consumer choice in electricity markets.

b) List two benefits of a competitive electricity market

A competitive electricity market leads to improved operational efficiency and reduced electricity prices due to competition among generators. It also encourages innovation and investment in new technologies, resulting in better quality of service for consumers.

c) Explain the role of an Independent System Operator (ISO) in a deregulated market

An Independent System Operator is responsible for ensuring the secure and reliable operation of the power system in a deregulated environment. The ISO manages system operation, maintains grid stability, coordinates power dispatch, and provides non-discriminatory access to the transmission network for all market participants.

d) Differentiate between Pool markets and Bilateral markets

In a pool market, electricity is traded through a centralized market where generators submit bids and loads submit offers, and the market clearing price is determined centrally. In a bilateral market, electricity transactions occur through direct contracts between buyers and sellers, with prices and quantities negotiated privately.

e) Explain the term “power wheeling”

Power wheeling refers to the transmission of electrical power from a generator to a consumer using a transmission network owned by a third party. It allows market participants to trade electricity over shared transmission infrastructure under regulated access charges.

f) Outline two pricing methods for power transactions in a deregulated market

Electricity pricing in deregulated markets can be based on marginal cost pricing, where prices reflect the cost of supplying the last unit of electricity, or through bilateral contract pricing, where prices are negotiated between buyers and sellers for long-term or short-term transactions.

g) Discuss ancillary services in power systems

Ancillary services are essential support services required to maintain system reliability and quality of supply. These include frequency regulation, voltage control, spinning reserve, and black start capability, which ensure stable and secure power system operation.

h) Importance of reactive power management in deregulated electricity markets

Reactive power management is critical in deregulated markets to maintain voltage stability and reduce transmission losses. Proper management ensures reliable operation, fair pricing of reactive power services, and efficient utilization of network resources.

i) Define reliability cost in power systems

Reliability cost represents the economic losses incurred due to power interruptions, reduced power quality, and system failures. It includes costs associated with outages, equipment damage, and loss of consumer confidence.

j) Explain the conflict between reliability and deregulation

The conflict between reliability and deregulation arises because competitive markets prioritize cost reduction, while reliability requires investment in infrastructure and reserves. Without proper regulatory oversight, market participants may underinvest in reliability-related assets.

SECTION B

(10 × 3 = 30 Marks)

2(a) Advantages, disadvantages, and example of deregulation

Deregulation offers advantages such as increased competition, improved efficiency, reduced electricity prices, and consumer choice. However, it also presents disadvantages including market volatility, increased complexity, and potential reliability issues. An example is the deregulation of the electricity sector in the United States, where competitive wholesale markets improved efficiency but required strong regulatory oversight.

2(b) Operational planning activities of GENCO in Pool and Bilateral markets

In pool markets, GENCOs participate by submitting bids based on generation costs and availability. In bilateral markets, GENCOs focus on contract negotiation, risk management, and scheduling to meet contractual obligations while optimizing profit.

2(c) Transmission open access and its impact

Transmission open access allows all market participants to use the transmission network on a non-discriminatory basis. It promotes competition, enables power trading, and enhances market efficiency, but also introduces congestion management challenges.

2(d) Ancillary services management in two countries

In the United States, ancillary services are procured through competitive markets managed by ISOs. In the United Kingdom, these services are procured through contracts and market-based mechanisms managed by the system operator to ensure reliability.

2(e) Role of stochastic modeling in reliability analysis

Stochastic modeling accounts for uncertainties in load demand, generation availability, and component failures. It helps evaluate system reliability by analyzing probabilistic outcomes and supporting informed planning decisions.

SECTION C

3(a) Benefits and aftereffects of deregulation

Deregulation improves efficiency, encourages competition, and reduces prices. However, it may lead to market power abuse, price volatility, and reliability concerns if not properly regulated.

3(b) Unbundling of electric utilities and its importance

Unbundling separates generation, transmission, and distribution activities to prevent monopolistic behavior. It enhances transparency, promotes competition, and enables fair access to the transmission network.

4(a) ISO’s role in operations planning and dispatch

The ISO performs operations planning by forecasting demand, scheduling resources, and ensuring system security. It dispatches generation resources economically while maintaining reliability and adhering to market rules.

4(b) Challenges faced by ISOs

ISOs face challenges such as managing congestion, ensuring reliability under competitive pressures, integrating renewable energy, and coordinating multiple market participants.

5(a) Congestion management methods

Congestion management is achieved through market-based pricing, re-dispatch of generation, use of financial transmission rights, and network expansion planning.

5(b) Security management techniques

Security management involves contingency analysis, real-time monitoring, reserve management, and emergency control actions to ensure stable system operation.

6(a) Reactive power management strategies

Reactive power is managed through voltage control devices, generator excitation control, reactive power markets, and coordinated planning to maintain voltage stability.

6(b) Interdependence of ancillary services and deregulation

Ancillary services support reliable system operation in deregulated markets by providing essential control functions, enabling competition without compromising stability.

7(a) Reliability determination methods

Reliability is determined using analytical, simulation, and probabilistic methods. Probabilistic methods assess system performance under uncertainty and are widely used in modern reliability studies.

7(b) Effects of deregulation on reliability

Deregulation can both improve and challenge reliability. While competition encourages efficiency, inadequate investment and poor coordination can reduce reliability if regulatory frameworks are weak.