Application of load survey systems to proper tariff design

This paper proposes a proper rate making strategy for a public own utility by taking into account the customer load characteristics. The load survey system has been well designed by sampling theory to find the customers for power consumption information collection. By this manner, the typical load patterns derived can effectively represent the load behavior of each customer class. The load patterns of each test customer during different seasons are solved by statistic analysis according to the load information collected. The seasonal typical load pattern of each customer class is then determined by integrating the load patterns of the same type customers. The power consumption of the customer class is then estimated by the typical class load pattern and the energy consumption of all customers in the same class, which can be retrieved from the customer information database. The typical load pattern of whole power system is then, determined by aggregating the power consumption of all customer classes. The estimated system load consumption is then compared to the actual system load profile, it is found that rather accurate system load profile can be predicted by the load survey system. To design a proper tariff structure for the utility by considering the power consumption profiles of all customer classes, the cost of delivering the power to the customers during different periods is calculated based on the actual cost of generation, transmission and distribution systems. The electricity service cost of each customer class during peak, shoulder and off peak periods is calculated, according to the contribution of each customer class to the whole system load profile. It is believed that the utility tariff rate structure derived by the proposed method will reflect the actual power cost of the utility to serve various types of customers in a more impartial way.