یک مدل مفهومی پویایی سیستم برای خرده‌فروشی منبع برق و سیستم تقاضا برای کمینه کردن هزینه خرده‌فروشان در شرق استرلیا

In eastern Australia's electricity market, the retailers have to purchase a certain amount of power to fulfill their customers’ demand. When the purchased power through forward contracts exceeds the electricity demanded by customers it leads to retailer's loss. On the other hand, the demand is higher than the purchased power which urges the company to buy extra power from a peaking power generator at electricity market with volatile price. This research studies power supply and demand systems at electricity retail market. System Dynamics (SD) methodology is used to investigate the influence of weather and forward contract conditions on the fluctuation of energy supply and demand in order to minimize energy retailer's cost. A respective conceptual model has been built by using qualitative phase in SD approach which enables further development in the SD's quantitative phase.

in eastern Australia's electricity market covering the Australian Capital Territory ,New South Wales, Queensland,South Australia, Victoria and Tasmania, customer demand is not supplied directly by power generators. Instead, the demand is fulfilled by energy retailers who purchase electricity from the generators or sellers and package it with transportation services before distributing to consumers. The electricity purchases could be made on regular basis for long or medium term periods called forward contracts at financial markets or irregular basis at an electricity spot market, namely the National Electricity Market (NEM). If the forward contract volume is not sufficient at a certain trading interval, then the spot contract is required to meet the demand [1]. Ho wever, the spot market price is so volatile which might lead to retailer's financial loss in substantiol amounts [2]. Moreover, it could result in bankruptcy as it happened at Texas Commercial Energy (TCE), a US electricity retailer in February 2004 [3].The demand of electricity fluctuates over time caused by some important factors, particularly weather conditions. Therefore, how the dynamic behavior of retail electricity market system under forward contract volume and weather condition changes is the question in this re search. The aim of this research is to support electricity retailers in managing their forward contract with power generators in a financial market under weather change and power market environment in eastern Australia in order to minimize their cost. The research objective is to deve lop a system dynamics conceptual model to evaluate the effects of forward contract volume and weather conditions on retailer's cost.

system dynamics conceptual model of retail electricity market in eastern Australia containing a causal loop diagram and a stock-and-flow diagram to evaluate the effect of forward contract quantity and we ather conditions on electricity retailer's cost has been eveloped. The model is built using the qualitative phase of system dynamics methodology. The retailer's cost is calculated from the cost of forward contract obtained at financial market and the cost of spot contract at spot contract. For further development, the conceptual model could be enhanced by employing the next phase in the SD approach, called the quantitative phase.