Smart Home Device Energy Savings Calculator
Estimate your annual energy and cost savings by switching to smart home devices including smart thermostats, smart plugs, and LED lighting.
Electricity Rate
Smart Thermostat
Smart Plugs / Standby Power Reduction
LED Smart Lighting
Formulas Used
Smart Thermostat Savings:
kWh_saved = HVAC_annual_kWh × (thermostat_savings_% ÷ 100)
Smart Plug Standby Savings:
Annual_standby_kWh = (standby_watts ÷ 1000) × standby_hours_per_day × 365
kWh_saved = Annual_standby_kWh × (plug_savings_% ÷ 100)
Smart LED Lighting Savings:
kWh_saved_base = bulbs × ((old_watts − new_watts) ÷ 1000) × hours_per_day × 365
kWh_saved_dimming = (bulbs × (new_watts ÷ 1000) × hours_per_day × 365) × (dimming_% ÷ 100)
Total_lighting_kWh_saved = kWh_saved_base + kWh_saved_dimming
Cost Savings:
Cost_saved ($) = Total_kWh_saved × electricity_rate ($/kWh)
CO₂ Avoided:
CO₂_saved (kg) = Total_kWh_saved × 0.386 kg CO₂/kWh
Assumptions & References
- Smart thermostats reduce HVAC energy use by 10–15% on average (U.S. DOE, ENERGY STAR).
- Standby/vampire power accounts for ~5–10% of residential electricity use (Lawrence Berkeley National Laboratory).
- Smart plugs can eliminate 50–80% of standby power by cutting power to idle devices.
- LED bulbs use ~75–85% less energy than incandescent bulbs (U.S. DOE).
- Smart dimming and scheduling can reduce LED lighting energy use by an additional 10–20%.
- U.S. average electricity rate: $0.13/kWh (EIA, 2023). Adjust to your local rate.
- CO₂ emission factor: 0.386 kg CO₂ per kWh (U.S. EPA eGRID 2023 national average).
- Savings do not account for device purchase costs or installation fees.
- Actual savings vary by climate, usage habits, utility rates, and device models.