This post is part of my Sustainable House Day submission.
Have you heard of the Aurora (Tasmania) electricity tariff 93? It was originally known as the Time-Of-Use (TOU) tariff but appears to have been recently rebranded as the Peak-and-Off-peak tariff.
Most households use a combination of tariff 31 for light & power, and tariff 41 for heating & hot water.
Sustainable Living Tasmania did a huge data collection/ modeling exercise with 100 real households and a further 1000 spreadsheet variations, and determined that 95% of households would be better off switching from tariff 31/41 to tariff 93. The more energy you use, and the more energy you can time-shift to off-peaks periods, the more money you can save.
Note that tariff 93 requires a meter that can periodically transmit your power usage back to Aurora via radio. You need to factor in an electrician changing your meter if necessary. This will affect the payback calculations. As far as I can tell, there’s no other fee for switching between tariffs.
In summary from a 2019 Aurora PDF and current pricing:
Using our electricity monitoring device we were able to record the total energy used each hour for the last 8 months. From this the following was determined:
|T93 /kWh off-peak||T93 /kWh peak||T93 daily||T93 total||T31 /kWh||T31 daily||T41 /kWh||T41 daily||T31/41 total|
To some $239 probably doesn’t sound a lot. And (sadly) the more energy you use, the more you will potentially save. With high fixed daily charges, there’s not much incentive to save more power below a certain amount.
In order to take full advantage of this new tariff you should move as much of your energy use into an off-peak period. Obviously for some households and some power consuming devices, this will be next to impossible. As already mentioned, for most households, there will already be savings to making the switch.
For example a saving may be made by putting a mains timer on the hot water cylinder, and only heating during off-peak times. Some estimates suggest 20% of Australia’s total power generation goes into heating hot water, and may be your 2nd highest energy cost!
A recent Solar Quotes blog post mentions a clever device that can divert excess solar power into any household load instead of getting paid a pittance as an $0.08/kWh feed-in tariff.