Time-of-Use Electric Rates: How I Gamed My Utility and Cut My Bill 40%
I want to be careful with the word “gamed” here, because what I actually did was completely above-board — I just read my utility’s tariff documents more carefully than they expected any residential customer to. What I found was a pricing structure that, combined with solar and a few behavioral changes, cut my electric bill by 40% beyond what solar alone would have accomplished. And the utility is totally fine with it. It’s literally the deal they’re offering.
Here’s how Time-of-Use rates work, how I discovered them, and exactly what changes I made. I’ll give you the numbers.
What Time-of-Use (TOU) Rates Are
Most residential electric customers are on a flat rate: you pay the same per kWh regardless of when you use electricity. Mine was $0.13/kWh before any of this. Simple to understand, and — as I discovered — not actually the best deal my utility offers. (That discovery started when my bill hit over $400 in a single month and I started seriously researching my options.)
Time-of-Use rates split the day into pricing periods. The grid is under the most stress during peak hours, typically late afternoon into evening when people get home from work and the sun is starting to set. During these hours, electricity costs more. During off-peak hours — overnight, early morning, and midday — electricity costs less, sometimes significantly less.
My Ohio utility’s TOU structure (and yours will vary, so look this up for your specific provider):
- On-peak: 4 PM – 9 PM weekdays. Rate: $0.21/kWh — 62% higher than my old flat rate
- Off-peak: all other hours. Rate: $0.08/kWh — 38% lower than my old flat rate
- Weekends and holidays: off-peak all day
At first glance, this looks like it might be a bad deal — peak hours are expensive. But here’s the thing: peak hours are when my solar system is producing at or near its maximum output. The math gets interesting very quickly.
How Solar Changes the TOU Equation
Without solar, TOU rates are a behavioral challenge: you have to shift your usage patterns to avoid expensive hours, and if you fail to do that consistently, you pay more than on a flat rate. For people with predictable schedules, it’s manageable. For others, it’s a trap.
With solar, the dynamic inverts. During those expensive 4–9 PM on-peak hours, my system is still generating 2–4 kW of power depending on the season. All of that generation offsets grid consumption at the peak rate, effectively crediting me at $0.21/kWh instead of $0.13/kWh. This is the core TOU-plus-solar arbitrage that most solar salespeople don’t adequately explain.
Let me give you a specific example from last August:
- On a typical weekday afternoon, my system generated 4.2 kWh between 4 PM and 7 PM
- On flat rate, that would have offset $0.55 worth of grid consumption (4.2 × $0.13)
- On TOU rate, that same generation offsets $0.88 worth of peak consumption (4.2 × $0.21)
- Difference: $0.33/day just from the afternoon generation window
- Annualized over approximately 220 weekdays with meaningful afternoon production: roughly $73/year of extra value from the rate structure alone
That’s before accounting for the behavioral shifts I made.
The Behavioral Changes That Amplified Everything
Once I switched to TOU rates, I looked at every major electrical load in my house and asked: does this need to happen between 4 and 9 PM on weekdays?
The answer, for most things, was no.
Laundry
We were running 4–5 loads per week, mostly on weekday evenings out of convenience. A dryer cycle pulls 5,000W and runs 45–50 minutes — that’s about 4 kWh per cycle. At peak rates, that’s $0.84 per cycle. At off-peak rates ($0.08), it’s $0.32. Multiplied by 200 cycles per year, the shift to off-peak laundry saves about $104/year. The change: I set a reminder to run laundry on weekend mornings or after 9 PM on weekdays. My wife thought I was being ridiculous until she saw the numbers.
Dishwasher
Similar story. A dishwasher with a heated dry cycle uses about 1.5 kWh. We run it 5–6 times per week, usually after dinner — smack in the middle of peak hours. Using the delay start feature to run it at 10 PM instead costs $0.12 vs. $0.32 per cycle. About $62/year for just changing when we press start.
EV Charging
This is the big one for people who have electric vehicles. My Chevy Bolt has a 65 kWh battery, and I typically charge 15–25 kWh per week. At peak rates, that’s $3.15–$5.25 per week. At off-peak overnight rates, that’s $1.20–$2.00 per week. Annual savings from just shifting EV charging to overnight: roughly $100–$160. The Bolt has scheduled charging built in. Ten minutes of setup, permanent savings.
Tracking It All
None of this is particularly useful if you can’t measure it. I upgraded my whole-home energy monitoring with an Emporia Vue 3 energy monitor, which gives me circuit-level visibility and tracks peak vs. off-peak usage automatically. Being able to see exactly which appliances are running and when, in real time, changed how I think about home energy use entirely.
Before I had real monitoring, I was guessing. With it, I discovered that my basement workshop equipment — two bench grinders and a drill press that I rarely use but leave plugged into power strips — was drawing 30–40W constantly in standby. Minor, but the kind of thing you’d never know without actual circuit monitoring. I also found that my old refrigerator was cycling more frequently during peak hours (hotter ambient temperature in the afternoon) and costing more than I expected.
For scheduling individual appliances that don’t have built-in timers, smart plugs with energy monitoring and scheduling are genuinely useful tools. I use them on the chest freezer in the garage (pre-cool before peak hours, let temperature coast during peak), on the workshop equipment (prevent standby draw), and on a few other always-on loads. They’re inexpensive and pay for themselves within a few months.
The Actual Numbers: Before and After
Here’s what my electric bill looked like over a trailing 12-month period:
- Pre-solar, flat rate: Average $187/month, $2,244/year
- Post-solar, flat rate (what my utility originally assigned): Average $41/month, $492/year
- Post-solar, TOU rate with behavioral shifts: Average $34/month, $408/year
The TOU switch added about $84/year in savings beyond what solar alone delivered on the flat rate. That sounds modest, but it required exactly zero additional capital investment — just a rate change request and some schedule adjustments. On a dollars-per-hour-of-effort basis, it’s one of the highest-return things I’ve done with this system.
More significantly, TOU rates change how you think about your solar investment going forward. Every kilowatt-hour of production during peak hours is worth 62% more than it was on the flat rate. As electricity prices increase over the next 25 years, that multiplier compounds. The solar system I sized to my flat-rate usage is now economically more valuable because I structured the rate around it properly.
How to Find Your Utility’s TOU Options
Not every utility offers TOU rates, and the specific structure varies enormously. Here’s how to find out:
- Go to your utility’s website and look for “Rate Options,” “Rate Schedules,” or “Tariff Information”
- Call your utility’s residential customer service line and specifically ask: “Do you offer Time-of-Use or time-variant pricing for residential customers?”
- If yes, ask for the actual tariff document — not the marketing summary — and review the peak/off-peak windows and rates
- Model your actual usage against the new rate structure before switching. In rare cases, TOU rates disadvantage households that can’t shift usage patterns.
In Ohio, AEP Ohio, Ohio Edison, and Columbus Southern Power all offer some form of TOU or optional rate structures. Your utility may be different. Do the legwork — it took me about an hour of research and a 20-minute phone call, and it’s saving real money every month.
If you’re still in the solar planning phase, I’d suggest investigating TOU rates before you even finalize your system size. For how TOU rates factor into the actual ROI math, see my 14-month solar ownership numbers — I include the TOU-adjusted savings in the full breakdown. The rate structure affects what size system makes economic sense and how you should orient panels if you have any flexibility. Getting this right at the front end is better than optimizing around it afterward.