{"id":24430,"date":"2018-10-23T10:25:17","date_gmt":"2018-10-22T23:55:17","guid":{"rendered":"https:\/\/www.solarquotes.com.au\/blog\/?p=24430"},"modified":"2018-12-13T18:20:41","modified_gmt":"2018-12-13T07:50:41","slug":"batteries-time-of-use-tariffs","status":"publish","type":"post","link":"https:\/\/www.solarquotes.com.au\/blog\/batteries-time-of-use-tariffs\/","title":{"rendered":"Are Time-Of-Use Tariffs The Secret To Fast Battery Payback?"},"content":{"rendered":"
\"Time

Do batteries save money with time-of-use tariffs?<\/p><\/div>\n

Home battery systems continue to fall in price — with an exception or two<\/a> — and we are getting closer to the day when they will save a typical household money without subsidy or being part of a Virtual Power Plant.<\/p>\n

But there is one thing that almost gets batteries to pay for themselves right now: the ridiculously expensive peak rates some time-of-use electricity tariffs charge. \u00a0But, without a subsidy, time-of-use tariffs and batteries will only save money for a few exceptional households.\u00a0 This is the case in NSW where time-of-use tariffs are high and in Western Australia where they are the most favorable for batteries.<\/p>\n

WA Has The Highest Time-Of-Use Tariffs<\/h2>\n

When I started researching this article I was confident NSW would still have the highest time-of-use electricity tariffs, but it turns out the winner of this dubious distinction is Western Australia.\u00a0 The image below is from Western Australia’s Synergy website<\/a> and shows their time-of-use tariff in all its expensive glory:<\/p>\n

\"Western

(Image: Synergy)<\/p><\/div>\n

This tariff is offered by Synergy in WA’s South West Interconnected System.\u00a0 This is the area shown in green on the map below that I stole from Infinite Energy’s site:<\/p>\n

\"Synergy

Western Australia’s South West Interconnected System (Image: Infinite Energy<\/a>)<\/p><\/div>\n

Outside of the green area grid electricity is supplied by Horizon rather than Synergy and they don’t offer time-of-use tariffs.<\/p>\n

While there are time-of-use tariffs worse than Synergy’s in NSW, you’d have to be crazy to use them as there are much cheaper ones available.\u00a0 Here’s a graph comparing an available Sydney time-of-use tariff with Synergy’s.\u00a0 I’ve also added in the solar feed-in tariff<\/a> so you can see it’s considerably better than what you get in WA.<\/p>\n

\"NSW<\/p>\n

While this article is going to focus on Western Australia, the basic conclusions will hold true for NSW, except batteries will be even less likely to pay for themselves there.<\/p>\n

My Hypothetical Household<\/h2>\n

Let’s say I move to Perth and buy a house with a north facing 6.5 kilowatt solar system<\/a>.\u00a0 And let’s also say my home uses an average of 18 kilowatt-hours of electricity a day from 3pm to 9pm, which is the weekday peak period.\u00a0 This is well above average as the typical Perth home uses less than this in a full day.\u00a0 I have no idea why my home consumes this much electricity.\u00a0 Maybe I married a robot.<\/p>\n

\"\"<\/p>\n

Also, because I’m so sexy, I’m going to assume I can get a great deal and have a solar battery system<\/a> installed for only $1,000 per usable kilowatt-hour.\u00a0 Because I like round figures I will spend $10,000 and get 10 kilowatt-hours of usable energy storage.\u00a0 This battery has a 10 year warranty, which is typical, but I am going to assume it will last 13 years.\u00a0 Because batteries degrade with use and time they can’t be expected to last well beyond their warranties<\/a>, as things like refrigerators and laptops generally do.<\/p>\n

To sum up I have:<\/p>\n