Keep cool in San Diego without feeding peak-hour rates
The summer playbook is simple: cool the house before 4 PM, block heat before it gets inside, and use personal cooling during the expensive 4 PM to 9 PM window.
Shift cooling earlier
Pre-cool before 4 PM so the AC runs less during peak pricing.
Cool people, not rooms
Fans, cooling towels, and neck cooling can preserve comfort at a higher thermostat setting.
Stop heat at the glass
Shading west and south-facing windows can reduce afternoon AC runtime.
Morning
Ventilate if outside air is cooler, close shades before direct sun, and set the home up before heat builds.
10 AM to 2 PM
Use the lower mid-day TOU window for chores, pre-cooling, pool pumps, or other flexible loads where your plan supports it.
2 PM to 4 PM
Pre-cool the rooms you will use during peak and avoid adding heat with cooking or laundry.
4 PM to 9 PM
Raise the thermostat, use fans or wearable cooling, keep shades closed, and avoid major appliances.
After 9 PM
Run delayed chores, cool bedrooms for sleep, and ventilate if the outdoor temperature has dropped.
Run the AC harder before peak pricing, then let the house coast through the most expensive hours.
- Cool the home from roughly 1 PM to 4 PM when rates are lower than 4 PM to 9 PM.
- Lower the thermostat 2 to 4 degrees before peak, then raise it during peak.
- Close interior doors to rooms you do not need cooled during peak hours.
- Use ceiling fans during peak so the higher thermostat still feels comfortable.
Best first move for TOU-DR1 and TOU-DR2 customers with central AC.
Personal cooling can make a warmer room feel comfortable without paying to chill the whole house.
- Use a neck fan or wearable neck air conditioner while working, cooking, or relaxing.
- Keep a small desk fan pointed across your upper body instead of cooling unused rooms.
- Use cooling towels, breathable clothing, and a cold drink during 4 PM to 9 PM peak hours.
- Aim fans at people, not empty rooms. Fans help comfort, but they do not lower room temperature.
Useful for avoiding a thermostat drop during expensive peak hours.
The cheapest cooling is heat that never enters the home.
- Close blinds and curtains on south and west-facing windows before the afternoon sun hits.
- Use blackout curtains, exterior shade, solar screens, or removable window film in hot rooms.
- Prioritize the room with the most afternoon sun if you only upgrade one window.
- Keep garage doors closed during hot afternoons to reduce heat transfer into the house.
Often lowers AC runtime without changing comfort.
San Diego nights and mornings can do some of the cooling work if you time airflow carefully.
- Open windows in the early morning or late evening only when outdoor air is cooler than indoor air.
- Use a window fan to exhaust warm indoor air and pull cooler air through shaded windows.
- Close windows before the outdoor temperature climbs back above the indoor temperature.
- Avoid bringing in humid coastal air if it makes the home feel sticky or harder to cool later.
Good for coastal and inland mornings, but timing matters.
Appliances can heat the house and force the AC to work harder during the worst rate window.
- Run the dryer, dishwasher, and oven before 4 PM or after 9 PM.
- Cook outside, use a microwave, or use an air fryer instead of heating the kitchen with the oven.
- If it fits how you cook, a portable induction burner can add less waste heat to the kitchen than gas or conventional electric resistance cooking.
- Run pool pumps and EV charging in super off-peak periods when your plan allows it.
- Delay laundry until late evening if the house is already warm.
Cuts both appliance cost and extra AC load.
Small HVAC problems are expensive when SDG&E peak rates are high.
- Replace dirty filters before the first real heat wave.
- Check that supply vents are open and not blocked by furniture.
- Seal obvious duct leaks and weatherstrip doors where hot air leaks in.
- Set a smart thermostat schedule around 4 PM to 9 PM instead of manually reacting once the house is hot.
Helps every hour the AC runs.
Neck air conditioning and fans are not replacements for safe indoor temperatures, but they can help avoid lowering the thermostat during peak hours.
Neck fan
Very low power, usually battery-powered
Best for: Walking around the house, cooking, garage tasks, light chores
Watch for: Moves air rather than actively cooling it, so performance drops in very hot rooms.
Wearable neck AC
Rechargeable battery, typically still far below room AC usage
Best for: Desk work, gaming, reading, and peak-hour comfort without lowering the thermostat
Watch for: Check weight, noise, battery life, and whether it uses cooling plates or only fans.
Desk or tower fan
Low power compared with AC
Best for: A fixed work area, bedroom, or couch setup
Watch for: Turn it off when leaving the room because fan benefit is mostly personal comfort.
Do not let bill savings override health. Older adults, infants, pets, and people with health conditions may need lower indoor temperatures during heat waves.
Use personal cooling as a comfort multiplier, not as permission to stay in unsafe heat. If the home is not cooling properly, treat that as an HVAC or safety problem rather than a rate optimization problem.
Check the math against your actual usage
A pre-cooling strategy works best when it fits your actual SDG&E rate plan and hourly load shape.