A security-constrained bid-clearing system for the New Zealand wholesale electricity market

Abstract

CT -This paper reports upon the mathematical models and implementation of the Scheduling, Pricing, and Dispatch (SPD) application for the New Zealand Electricity Market (NZEM). SPD analyzes bids for energy offers, reserve offers and energy demands, and recognizes explicitly the effects on bid clearing due to transmission congestion, network losses, reserve requirements, and ramp rate limits. Advanced LP sollution methods are utilized to solve the large-scale constrained optimization problem. Results on a 67-bus test system and the NZEMI are included.

Dispatching power and ancillary services in autonomous network-based power systems

“…For instance, if there is a severe contingency in the outside system, AN can decide to disconnect from the system and operate as an island, presenting uninterruptible power supply for a set of its sensitive loads (for instance hospitals). This high level of security for those loads can be included in A...., and B...., (5). These constraints can state that AN must have required amount of spare capacity so that successful transition to island operation is possible at any time.…”

“…In [4], bids are selected to minimize total system costs while the Market Clearing Price (MCP) is determined as the price of the highest accepted bid. In [5], [7] and [8] a bidclearing system is presented. Detailed models are used.…”

LP models for pricing diffuse nitrate discharge permits

“…To facilitate trade in nitrate loading permits, we propose a centrally mediated multilateral trading system similar to the New Zealand electricity market (Alvey et al 1998). The dominant feature is the use of an LP which optimizes the trading of permits between participants, and determines equilibrium prices, so as to maximize the benefits of trade, as defined by the offers and bids submitted by market participants.…”

“…The optimal allocation may be modelled as a mathematical program, often a linear program (LP), from which the equilibrium prices may be obtained straight off. This is the lesson that the environmental policy makers could learn from the modern electricity markets, which use LPs to clear the markets and set the prices instantaneously (Alvey et al 1998;Hogan et al 1999). The similarity is that both are common pool multilateral trading problems with complex interactions and constraints.…”

Load As A Reliability Resource in the Restructured Electricity Market

“…A price is established for each half-hour trading period by a simple merit ordering of generator offers. Bids and offers are received by hour 13:00 on the day ahead, and generators are dispatched in order of increasing offer price until the total demand bid is met [24]. Forecast prices are established at each of 244 nodes of the grid as the shadow prices resulting from a security constrained optimization.…”