Tip
Lower water heating costs by 10-25%
Water heating is the second-largest residential energy use after HVAC. Most adjustments cost nothing or under $50.
1. Set the thermostat to 120°F
Most U.S. water heaters ship at 140°F. 120°F is hot enough for sanitation and comfortable showering, slows tank corrosion, and saves 4-15% per year. (Reduce further only if no immunocompromised household members — Legionella becomes a concern below 120°F.)
2. Insulate the tank and first 6 feet of pipe
A water heater blanket ($20-$30) reduces standby losses by 25-45% on older units. Pipe insulation on hot water output prevents heat loss as water travels to fixtures.
3. Fix dripping faucets immediately
A faucet dripping 1 drop/second wastes 2,082 gallons of hot water per year. Tankless and heat pump water heaters lose efficiency on the high end of demand; minimizing leaks compounds savings.
4. Install low-flow showerheads (1.5-1.75 GPM)
Federal max is 2.5 GPM. WaterSense-labeled fixtures at 1.5-1.75 GPM cut hot-water demand 30-40% with no comfort impact. Many utilities give them away free.
5. Use cold for laundry
Modern detergents are formulated for cold water. 90% of laundry energy is heating water — washing in cold cuts that to ~10%.