I’m Joe from Smarta Switch in Brisbane. If your business is on a time-of-use tariff, your bill has a quiet superpower most owners never use: when you run your power can matter almost as much as how much you use. Move some usage out of the expensive peak window and you save money without cutting back at all. Here’s how peak, shoulder and off-peak actually work, in plain English.
We’re paid by the energy retailer when you switch, never by you.
The basic idea
On a flat tariff, every unit of electricity costs the same, day or night. On a time-of-use tariff, the price changes depending on the time of day, because electricity genuinely costs more to supply when everyone wants it at once. There are usually three bands:
- Peak, the most expensive. The hours when demand on the grid is highest.
- Shoulder, the middle rate. The hours either side of peak.
- Off-peak, the cheapest. Overnight and quiet periods when the grid is relaxed.
The gap between peak and off-peak rates can be large, off-peak can be a fraction of the peak price. That gap is the opportunity.
The rough time windows (South East Queensland)
Time-of-use windows vary by network, retailer and your exact tariff, so always confirm yours on your bill or plan, but as a general SEQ guide:
- Peak: typically weekday late afternoons into the evening, roughly the after-work window when household and business demand overlap.
- Shoulder: the daytime and mid-evening hours either side of peak.
- Off-peak: overnight, early mornings, and often all weekend.
The exact hours are set by your tariff, and they do shift between plans, so don’t run your business off this guide alone, check your actual windows. But the shape is consistent: evenings cost most, nights cost least, weekends are usually cheap. (Your tariff type decides whether this even applies to you, here’s how to find it.)
The rule of thumb: weekday evenings are dear, overnight and weekends are cheap. Shift what you can into the cheap windows and the bill falls, even if your total usage doesn’t change at all.
How to actually use this to cut your bill
You don’t need to rewire anything. You need to ask: what do I run that doesn’t care what time it runs? Those are your candidates to shift off-peak.
- Cold rooms, freezers and fridges. Pre-cool harder during off-peak so they coast through peak. Maintenance and defrost cycles, schedule them overnight.
- Hot water and heating. Heat water overnight on off-peak where your system allows.
- Pool pumps, irrigation, water features. Timer them to off-peak. Easy win, zero downside.
- Charging anything, EVs, tools, forklifts, batteries. Charge overnight, not over the dinner rush.
- Dishwashers, laundry, heavy equipment runs. Where the workflow allows, push them to shoulder or off-peak rather than smack in the peak window.
- Battery storage. If you have one, charge off-peak and discharge through peak. That’s the whole economic case for a commercial battery on a time-of-use tariff. (More on switching with solar or a battery.)
Even shifting 10–20% of your flexible load out of peak can take a visible bite out of the bill.
Time-of-use vs demand charges, don’t confuse them
This trips people up constantly, so let’s be clear:
- Time-of-use is about when you use energy. Cheaper at night, dearer in the evening peak. It’s a per-kWh rate that changes by clock.
- Demand charges are about your single biggest spike of power, regardless of how long it lasts, often measured in kVA. One bad surge can set your demand charge for the whole month.
A site can have both. Shifting usage off-peak helps your time-of-use rates; staggering your start-up so everything doesn’t switch on at once helps your demand charge. Different levers, both worth pulling. (Demand charges explained in full.)
Is time-of-use even right for you?
Time-of-use isn’t automatically cheaper. It rewards businesses whose usage naturally falls outside peak, and punishes those whose busiest hours are the peak window.
- Good fit: early-morning operations (bakeries, gyms), overnight processes, weekend-heavy trade, anything with shiftable load.
- Bad fit: a business slammed precisely during the weekday evening peak with no flexibility, a flat tariff might genuinely serve you better.
This is exactly why the tariff structure check matters. The wrong structure for your hours costs you every month, quietly. (How to spot a tariff mismatch.) The honest answer for some businesses is “go flat,” and a good review will tell you that. (More ways to lower a commercial bill.)
What to do this week
- Check your bill for time-of-use. If you see peak/shoulder/off-peak split out, you’re on it. If it’s one flat rate, you’re not (and this guide is your case for considering it, if your hours suit).
- Confirm your actual windows. Don’t guess from this guide, read the exact peak/off-peak hours on your plan.
- List your shiftable load. What runs that doesn’t care about the clock? That’s your savings list.
- Get your tariff and rate reviewed together. Upload your bill on this page or email hello@smartaswitch.com.au. I’ll tell you whether time-of-use suits how you actually trade, and whether your rate is sharp within it. No cost, no commitment, because we’re paid by the energy retailer when you switch, never by you.
Same electricity, different clock, different bill. For a lot of Brisbane businesses, that’s free money sitting in the timing.
Joe Lawrence, Co-founder, Smarta Switch Australia 0435 642 592 · joe@smartaswitch.com.au