Time-of-use (TOU) tariffs price electrons by the clock. Utilities recover grid stress with high on-peak cents per kWh—often late afternoon into evening when air conditioning and cooking overlap. Your job is not heroic deprivation; it is moving flexible loads into cheap hours without breaking comfort rules you actually care about.
What flexes and what does not
Flex: EV charging, clothes dryer, dishwasher, pool pump, water heater (with timer or heat-pump control), battery storage charge schedule.
Inflexible: mid-day remote work cooling, medical devices, occupancy sensors you will not override.
Automation beats willpower
Smart breakers, appliance delay buttons, and charger apps that respect off-peak windows outperform sticky notes. Set EV to finish by departure time, not "start when plugged in" if plug-in happens at 6 p.m. on-peak.
Stacking behaviors for compound savings
One shifted EV session might save three to eight dollars per fill depending on tier spreads. Add dryer and dishwasher overnight on the same super-off-peak block and savings climb without new hardware—provided your panel and noise rules allow it.
Baseload that never shifts—TVs, consoles, and chargers on standby—still runs every hour. Estimate that drag with the Vampire Power Cost Calculator before you optimize only the flexible loads.
When shifting is not worth it
Flat legacy rates, weak peak/off-peak spreads, or demand charges on commercial service change the playbook—kW peaks may dominate kWh timing.
Battery arbitrage on top of TOU
Home storage can charge from grid off-peak and discharge during peak—or offset solar self-consumption. Economics need round-trip efficiency, cycle wear cost, and whether export is compensated.
Tariff literacy checklist
- Read your rate schedule label (e.g., EV-A, TOU-D-PRIME)
- Note summer vs winter peak hours—they change
- Confirm holidays treated as off-peak
- Re-run math after annual utility filing
TOU shifting is the cheapest demand response program you join voluntarily. Map your loads to the clock, automate the boring moves, and let peak pricing fund your off-peak lifestyle.