Review of EDD weather standards for Victorian gas forecasting


The Effective Degree Day (EDD) index was developed to capture the combined impact of temperature, wind and sunshine on Victorian gas demand. edd long term trend

Gas consumption due to short term weather variations is often removed prior to forecasting gas demand. This is partly achieved by developing weather standards that represent conditions under temperatures, for example, that are neither warmer nor cooler than expected. 

Weather standards for Victorian gas forecasting are typically developed using the Effective Degree Day index.

The Australian Energy Market Operator (AEMO), and previously VENCorp, have reviewed the EDD index and EDD standards every two to three years since 2000 with the latest completed in 2012.

The 2016 NIEIR Review of EDD Standards for Victorian Gas Forecasting report follows on from these reviews with a particular focus on the development of new weather standards for annual gas consumption and peak day to inform the Gas Access Arrangement Review (GAAR) over the 2018 to 2022 period.


This report covers:

  • background to weather normalisation and how the EDD index is formulated;
  • the development of new annual EDD standards under alternative methodologies;
  • the development of new 1-in-2 and 1-in-20 peak day EDD standards under alternative methodologies;
  • The impact of climate change on annual and peak day weather standards;
  • The correction applied to temperature to account for the change in location of the official Melbourne weather station from the CBD to Olympic Park in 2015 and;
  • monthly standards are also estimated for gas consumption and peak day.


Download the NIEIR Review of EDD weather standards for Victorian gas forecasting report:

Full Report    (26 pages | PDF | 1,328 kb)

Tables   (XLSX | 87 kb)