Understanding Time-of-Use Pricing
Electricity doesn't cost the same all day long.
For a lot of households, what you pay for a kilowatt-hour depends entirely on when you use it. Running your dishwasher, electric vehicle charger, or water heater during a busy time of day can cost way more than flipping them on just a few hours later.
This setup is called time-of-use (TOU) pricing. It’s becoming the new normal as power grids adapt to how we live today—balancing the rise of electric cars, home batteries, and renewable energy. Understanding the difference between peak and off-peak hours helps you figure out when power is most expensive so you can shift your heavier usage to cheaper windows.
What Is Time-of-Use Pricing?
Time-of-use pricing splits the day into different blocks, with rates changing based on how busy the grid gets.
The idea is simple: when everyone wants power at the exact same time, the grid is under stress, and electricity gets expensive. When demand drops, power companies offer cheaper rates to encourage you to use energy then instead.
Instead of paying a flat rate 24/7, a TOU plan usually breaks down into:
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Peak hours: The most expensive window.
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Off-peak hours: The cheapest window.
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Mid-peak (or shoulder) hours: Somewhere in the middle.
Every power company handles this differently, so there’s no one-size-fits-all schedule. A routine that saves you money in one city might not do much for you in another.
What Are Peak Hours?
Peak hours are the grid's rush hour.
In most neighborhoods, demand spikes when people get home from work or school. Air conditioners kick on, dinners go in the oven, cars plug in, and TVs light up—all within the same few hours. A typical peak window might run from 4 p.m. to 9 p.m. on weekdays, though your actual schedule depends on your provider.
During these hours, power can cost a lot more than it does in the middle of the night. If you're just running a laptop, you won't notice the difference. But for heavy appliances, it adds up fast.
Take an EV charging session that needs 30 kWh. If your peak rate is $0.45 per kWh, the energy cost for that charge is:
30 kWh × $0.45 = $13.50
If you wait and pull that same 30 kWh during an off-peak rate of $0.12 per kWh:
30 kWh × $0.12 = $3.60
That’s a $9.90 difference for a single charge. Do that a few times a week, and just changing the time on your clock makes a noticeable dent in your monthly bill.
What Are Off-Peak Hours?
Off-peak hours are the quiet times when demand drops.
These usually happen overnight while most people are asleep and businesses are closed. A common off-peak window might be 10 p.m. to 6 a.m., but you always have to check your specific plan to be sure. Some plans even break the night into a few different off-peak blocks rather than one long stretch.
The key takeaway is that power isn't automatically cheaper at night everywhere—it's only cheaper if your specific tariff is set up that way.
Why Do Power Companies Do This?
Time-of-use pricing is basically a nudge.
Grid operators have to balance supply and demand every second of the day. A massive spike in demand puts heavy stress on power plants and power lines. Instead of spending billions to build new infrastructure just to handle the 6 p.m. dinner rush, they offer a discount to shift the load.
If thousands of people delay their EV charging, laundry, or water heating until the grid calms down, everyone wins. You get a cheaper bill, and the utility gets an easier grid to manage.
What Can You Actually Shift?
You can't shift everything. Your fridge needs to run 24/7, and you usually want the heater on when it's freezing outside. But plenty of other appliances are easy to reschedule.
The biggest targets usually include:
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EV chargers
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Washing machines and dryers
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Dishwashers
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Water heaters
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Home battery systems
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Pool pumps
The goal isn't to stop using power entirely during peak hours. It’s just about finding the heavy loads that can wait. A dishwasher doesn't need to run the second dinner is over. If rates drop at 11 p.m., setting a delay timer cuts your cost without changing your actual routine.
The Math on Monthly Savings
Let’s say you figure out how to shift just 8 kWh of heavy usage every day from a $0.35/kWh peak window to a $0.13/kWh off-peak window.
Your daily savings:
8 kWh × ($0.35 − $0.13) = $1.76
Over a 30-day month:
$1.76 × 30 = $52.80
That’s over $630 a year staying in your pocket, just for changing when you push a button. Of course, actual savings depend on your specific rates, fixed fees, and how much power you can realistically move around.
Weekends Might Be Different
One of the easiest traps to fall into is assuming the schedule is exactly the same every day.
Some plans drop their rates entirely on weekends and holidays. You might find that all of Saturday and Sunday count as off-peak, making it the perfect time to run back-to-back loads of laundry or do a deep charge on an EV. Always read the fine print—don't just guess that the weekend is cheap.
The Cheapest Power Isn't Always at Night Anymore
Thanks to the boom in solar energy, the rulebook is changing.
Solar panels flood the grid with power during the middle of the day. In some markets, wholesale electricity gets incredibly cheap—sometimes even negative—around noon because there is so much solar being produced and not enough demand for it.
Because of this, smart tariffs are starting to reward people for using power in the middle of the afternoon rather than the middle of the night. It’s shifting from a fixed clock to a dynamic system that follows the sun.
What About EVs?
Electric cars and time-of-use pricing are a perfect match.
When you park in the garage at 6 p.m., the car doesn't need to start pulling power immediately. A smart charger lets you plug in, walk away, and tell the car to wait until rates drop at midnight before it actually starts charging. Some advanced tariffs even let the utility company decide the exact minute to start charging based on grid capacity, offering you a massive discount in exchange for that flexibility.
What If You Have to Use Power During Peak Hours?
Nothing bad happens—you just pay the higher rate.
If you need to run the dryer immediately, run it. The trick is just knowing the math. Once you figure out which machines draw the most power, you can make a calculated choice about whether it's worth the convenience of doing it now versus the savings of doing it later.
Before you change any habits, pull up your actual utility bill. Look for your peak windows, your off-peak rates, weekend rules, and any fixed daily charges. A plan with an incredibly cheap night rate might hide high fixed fees, so you want the full picture.
From Home Appliances to Heavy Hardware: The Mining Factor
Time-of-use pricing gets a lot more interesting when you’re dealing with hardware that pulls heavy power 24/7.
Cryptocurrency mining is the perfect example. An ASIC miner or a rigged-up GPU system eats up way more power than your standard home appliances. If your electricity rates jump around depending on the clock, when you mine directly impacts your bottom line.
But just firing up a miner during the cheapest six hours of the night isn't a magic fix. You have to balance hashrate, power draw, mining difficulty, hardware efficiency, and cooling constraints against those shifting rates.
How electricity tariffs impact mining profitability is a whole different ballgame. In our next breakdown, we’re going to dive specifically into crypto mining with ASIC and GPU setups under time-of-use pricing. We’ll look at how to sync your operating schedules with off-peak rates, run the math on profitability, and map out real strategies to squeeze the most out of cheap energy windows.
Because when it comes to mining, it’s not just about how much power a machine draws—it’s about what that power costs the exact second it pulls it from the grid.
FAQ
Q1: Wait, so my power company charges me different prices depending on the time of day?
Exactly. Think of it like Uber’s surge pricing. When everyone gets home from work and turns on the oven, A/C, and TV all at once, the grid gets stressed, so the power company charges you a premium. When most people are asleep and demand drops, the power goes on clearance.
Q2: So when is the absolute cheapest time to use power?
For most people, it's the middle of the night—usually between 10 p.m. and 6 a.m. But there’s a plot twist: if you live somewhere with a lot of solar energy, the cheapest time might actually be right in the middle of the afternoon when the sun is blasting. You have to check your specific rate plan to know your exact "cheap" hours.
Q3: Is it really worth the hassle of changing my schedule?
If you’re just shifting a single load of laundry, you might only save a couple of bucks a month. But if you’re charging an electric car, running a pool pump, or using a heavy electric heater, simply pushing a "delay start" button could literally keep hundreds of dollars in your pocket over a year.
Q4: Am I supposed to just sit in the dark during "peak" hours?
Not at all! Keep the lights on, watch TV, keep your Wi-Fi running. Normal electronics don't use enough power to ruin your bill. The goal is just to put off the "heavy lifters"—like the dishwasher, EV charger, and dryer—until the rates drop.
Q5: Are weekends cheaper?
On a lot of plans, yes! Many utility companies treat the entire weekend as off-peak. That makes Saturday and Sunday the perfect time to do back-to-back laundry loads or a deep charge on your car. Just make sure to double-check your plan first, because not every company is that generous.
Q6: I run crypto mining hardware. Does this actually matter for me?
Big time. ASIC and GPU rigs eat massive amounts of power non-stop. If you’re on a Time-of-Use plan, mining straight through that 5 p.m. to 9 p.m. peak window could literally wipe out your profits for the whole day. You have to run the math to see if it’s smarter to keep the machines humming 24/7 or pause them when electricity prices spike.
