Loss factors and regional boundaries

As electricity flows through the transmission and distribution networks, energy is lost due to electrical resistance and the heating of conductors. The losses are equivalent to approximately 10% of the total electricity transported between power stations and market customers.

Energy losses on the network must be factored in at all stages of electricity production and transport, to ensure the delivery of adequate supply to meet prevailing demand and maintain the power system in balance. In practical terms, this means more electricity must be generated than indicated in simple demand forecasts to allow for this loss during transportation.

The impact of network losses on spot prices is mathematically represented as transmission and distribution loss factors. Loss factors are calculated and fixed annually to facilitate efficient scheduling and settlement processes in the NEM.

Current reports

2020-21 Financial year

2019-20 Financial year

Previous reports

2018-19 Financial year

2017-18 Financial year

2016-17 Financial year

2015-16 Financial year

2014-15 Financial year

2013-14 Financial year

2012-13 Financial year

2011-12 Financial year

2010-11 Financial year

2009-10 Financial year

2008-09 Financial year

Archived loss factor documents may be obtained upon request from the AEMO Information & Support Hub.

Indicative extrapolation input data for 2020-21 Marginal Loss Factors

AEMO conducted an indicative extrapolation study to assist generators in determining whether the historical generation data used by AEMO is reasonable for the 2020-21 MLFs calculation.

Indicative extrapolation input data for 2020-21 Marginal Loss Factors: