Adjusting the thermostat to a lower temperature at night can significantly save energy and reduce heating costs while maintaining comfort during sleep.
Adjusting your thermostat at night is one of the easiest ways to cut energy costs. Research shows you can save up to 10% annually by lowering temperatures 7-10°F for 8 hours. But how low should you go? And what about different heating systems?
Ideal Nighttime Thermostat Settings
The U.S. Department of Energy recommends setting your thermostat to 68°F (20°C) when awake and lower when sleeping or away. For most homes, these ranges work best:
| Season | Daytime Temp | Nighttime Temp |
|---|---|---|
| Winter | 68°F (20°C) | 60-62°F (15-16°C) |
| Summer | 78°F (25.5°C) | 82-85°F (28-29°C) |
Why These Temperatures Work
At night, your body temperature naturally drops during sleep. A cooler bedroom (60-67°F) actually promotes better sleep quality. The reverse applies in summer – slightly warmer temperatures align with your circadian rhythm.
How Different Heating Systems Respond
Gas/Oil Furnaces
Traditional furnaces see the greatest savings from nighttime setbacks. According to Dartmouth engineering dean Dr. Alexis Abramson, “Whenever you set the thermostat lower, you are saving energy – no matter what.” The longer your home stays at lower temperatures, the more you save.
Heat Pumps
Heat pumps work differently. Their efficiency drops as outdoor temperatures fall. For heat pump owners:
- Limit nighttime setbacks to 2-3°F
- Avoid turning completely off
- Consider a smart thermostat designed for heat pumps
Electric Resistance Heating
For baseboard heaters or electric furnaces, programmable thermostats are essential. Pair them with efficient electric heaters to maximize savings.
Advanced Strategies for Maximum Savings
Smart Thermostat Programming
The most effective schedules:
- Begin temperature drop 60-90 minutes before bedtime
- Maintain nighttime temperatures for 6-8 hours
- Start warming 30-60 minutes before wake-up
Home Preparation Tips
Winter Preparation
- Use heavy curtains to reduce heat loss
- Seal drafts around windows and doors
- Add area rugs on cold floors
Summer Preparation
- Use light, breathable bedding
- Install ceiling fans (reverse direction in winter)
- Keep blinds closed during daytime
Myths vs Facts About Thermostat Settings
Myth: It takes more energy to reheat a home than to maintain temperature.
Fact: Your home loses heat slower at lower temperatures, resulting in net savings according to U.S. Department of Energy research.
Myth: Setting extreme temperatures saves more.
Fact: Excessive setbacks (below 55°F in winter) may cause pipes to freeze and systems to overwork.
Special Considerations
Homes with Babies or Elderly
Maintain minimum 65°F in rooms used by vulnerable individuals. Consider localized heating with app-controlled space heaters instead of whole-home adjustments.
Vacation Settings
For extended absences:
- Winter: 55°F to prevent freezing
- Summer: 85°F to prevent humidity damage
Monitoring Your Savings
Track results through:
- Smart thermostat energy reports
- Utility bill comparisons
- Home energy monitors like Sense
According to ISO New England, nighttime electricity often has lower carbon emissions, making pre-dawn heating ideal for electric systems.
