G-ROI® calculations are based on the following statistics for U.S. offices:
- Number of U.S. office buildings: 736,000 buildings
- Total square footage of U .S. offices: 12,044,000,000 sq. ft.
- Percentage of offices relative to total U .S. properties (non-residential): 17.9%
- Average hours of office operation: 53 hours/week
- Average annualized hours of operation: 2,756 hours/year
- Average commercial cost of one kWh: 10.6 cents/kWh
- Annual electricity consumption for office lighting: 82 billion kWh/year
- Average traditional office lighting cost per sq. ft. per year: $0.72
- Pounds of CO2 saved for every $1 of electricity saved: 13 lbs
- Pounds of CO2 emitted annually for mid-sized SUV/ car: 12,000 lbs (6 Tons)
The G-ROI® calculations below are also based on key data for LED Lighting:
- LED kWh reduction over a blended average of traditional and fluorescent lamps: 50%
- LED lifetime expectancy: 50,000 hours
- Lifetime expectancy of LEDs for average offices given average operating hours: 18.1 years
- Average savings per foot/year with LEDs: $0.36
- To put this level of savings in context across the other types of properties, see Fig. 6 and Fig. 7 of this G-ROI® Report.
National Impact Data: The previous information was taken from U.S. Census, DOE, ENERGY STAR, and private sector data.