Billinton, R.2018-12-072018-12-071992-06June 1992http://hdl.handle.net/10388/11611A significant component of the overall system electrical energy requirements of many power utilities is now being provided by Non-Utility Generators (NUGs) and power/energy purchases from neighbouring systems. A NUG is defined in this thesis as an independent power production facility or cogeneration facility, which is not owned by the utility in whose service area the facility is located. These facilities are small generating capacity components associated with load points within the utility system. NUG capacity additions can have considerable impact on adequacy at both the individual load points and the overall system. The opportunity to wheel energy/power through the transmission facilities of one system in order to serve another system is one of the many possible uses and benefits of interconnection between neighbouring electric power systems. Wheeling of energy can also occur within a system when an independent power producer in a local utility system serves a load located at some other point in the system. Power wheeling transactions are recognised to have a definite impact on the utility's system losses depending upon the system topology, the amount of power/energy wheeled and the wheeling distance involved. These factors currently form the basis for determining service charges associated with power wheeling.Thesis