Western Power has reported very little impact to energy consumption as a result of daylight saving. In general the hotter and more humid the months are the more energy is used as a result of daylight saving.
Overall, energy consumption increased a marginal 0.35% over the 2008/09 daylight saving trial period.
To determine the impact of Daylight Saving (DLS) Western Power has modelled how much power would have been consumed with and without Daylight Saving.
Western Power's network (which covers the south west of WA from Kalbarri - Albany) is very weather sensitive and studies have shown that dry bulb temperatures explain roughly 80% of the weather-sensitive load swings. Relative humidity is used in the equations with the idea that hot and dry is not the same as hot and humid.
The following points are noted regarding this:
The analysis of the impact of DLS on energy has been based on performing a simulation of the summer days for the period to determine the expected energy consumption with and without DLS.
The simulation was performed using the MetrixND Forecasting Package used by System Management for Load demand forecasting. This method has been used to ensure that any errors inherent in using the forecasting process are minimised.
A mathematical formula combining the effects of temperature and humidity into a single weather concept known as the Summer Simmer Index (SSI) was used.
The results of the analysis indicate an increase of 0.35% energy due to DLS in 2008/09.
In general the hotter and more humid the months are the more energy is used as a result of DLS.
In 2006/07 energy consumption increased by a minimal amount of 0.60% during the Daylight Saving Trial. During the second trial period in 2007/08 energy consumption increased 0.44%. Western Power considers it likely that the greater increase in energy consumption during the 06/07 period was in part due to the late start of the trial, reducing the number of cool, less power consuming, days included in the trial.
Page update on 11 May 2009
