The global trend of reform in the electricity supply industry can be attributed to several factors, such as: the introduction Of competition in the industry as a means of providing lower energy prices; consumer demand for price transparency and regulation Of cross-subsidies among different users; need for higher energy efficiency in technical systems of utilities; significant growth in energy demand especially in developing countries; and pressure on governments to raise funds for social services, balance budgets and to carry out economic reform. Lower technical losses will provide for cheaper electricity and lower production costs with a positive influence on economic growth. This article evaluates technical losses in transmission and distribution systems, presents results of technical loss estimation in South Africa grid network, and discusses issues of loss minimisation and economic dispatch under a deregulated electricity supply industry.