How is the CO2 reduction estimated?

Q: How much money will a more efficient appliance save me per year?

The calculator converts each appliance to annual energy as kWh/yr = (watts x hours/day x days/yr) / 1000, then multiplies the kWh difference between the old and new unit by your electricity rate. For example, replacing a 1500 W unit with a 1000 W unit running 5 hours a day, 365 days a year, saves about 912 kWh, or roughly $110 at $0.12/kWh.

Q: What electricity rate should I use?

The field defaults to $0.12/kWh, a typical US residential average, but you should enter your own rate from your utility bill for an accurate dollar figure. Real-world duty cycles also often differ from rated use hours, so verify against utility data when available.

Question

How is the CO2 reduction estimated?

Accepted Answer

It multiplies the annual kWh saved by 0.92 lb/kWh, the US national grid-average carbon factor (EIA/EPA, roughly 2024). This is a rough national figure: coal-heavy grids such as WV, KY, and WY exceed 1.5 lb/kWh, while renewables-heavy grids like VT, ID, and WA run under 0.5, per EPA eGRID.

How is the CO2 reduction estimated?

Answers