Energy alance and Technical Losses in an Electrical Network

For a network operator or technical project developer, drawing up an energy balance and determining the electrical losses on a network are relevant technical and economic indicators for monitoring performance and enhancing the value of a project.

The purpose of this article is to present and detail the methods used to determine these two tools:

• the energy balance, a physical tool that draws up an inventory of energy flows in an area, noting incoming flows (injections) and outgoing flows (consumption and losses);

• evaluation of the technical energy losses inherent in any system (Joule effect heating, iron and corona losses, etc.), which can be modelled and estimated deterministically or at least statistically. During marketing, these losses are compounded by "non-technical" losses that can only be deduced: commercial losses, fraud, counting errors, errors in customer files, etc. Asynchronous index readings add a further element of complexity to the problem.

Various tools and methods applied to traditional network structures will be proposed, based on available data sets. These will enable an analyst or operator to implement a robust theoretical and conceptual approach to carrying out a comprehensive energy balance.

The fineness of the data determines the accuracy of the calculation, but the various methods developed in this article will be consistent with the data available. Uncertainties on the values will be inherent to the method, but the result must give a clear indication of the energy balance of the system under consideration, and of the uncertainties to be taken into account.

The aim of this article is to present a method-tool for evaluating an energy balance sheet over a past period, in order to give a picture of the technical, and even financial, state of health of an electricity company, or of a territory within this company, at a given point in time. From this method, the results of which will represent a decision-making tool, an action plan can be deduced to reduce technical and non-technical losses.