Natural Gas: Collective Annual Savings
If every California household upgraded to a... | Energy Savings* | CO2 offset | Dollars saved | Cars off the road |
---|---|---|---|---|
ENERGY STAR Qualified Central Natural Gas Furnaces | 255 million Therms | 1.4 million metric tons | $230 million | 235,000 cars |
Energy-Efficient Gas Storage Water Heaters | 100 million Therms | 552,000 metric tons | $91 million | 92,000 cars |
Energy-Efficient Dishwashers | 254 million Therms 188 million kWh |
235,000 metric tons | $52 million | 42,700 cars |
Energy-Efficient Clothes Washers | 7.8 million Therms 40 millionn kWh |
61,000 metric tons | $14 million | 11,000 cars |
* The savings estimates compare efficient models to conventional models of the same product.
** Figures based on $0.14/kWh and $0.90/therm residential rate.
Assumptions for Calculations
Example 1: Furnaces
If all California households with old, inefficient (80 AFUE) central gas furnaces upgraded to ENERGY STAR qualified models (90 AFUE), it would save 255 million Therms and 1.4 million tons of CO2 per year (equivalent to taking 252,000 cars off the road).
Sources and Assumptions
- 12 million households in California (U.S. Census, April 2007)
- 12 lbs CO2 per Therm (California Climate Action Registry, April 2007)
- 12,100 lbs of CO2 per car per year (U.S. EPA Personal Emissions Calculator, April 2007)
- 70 Therms saved per furnace per year (ENERGY STAR savings calculator for Central Gas Furnances for 2,500-sq.-ft. house in Pacific region)
- 62.8% Central Gas Furnace saturation rate statewide (2005 California Statewide Residential Lighting and Appliance Efficiency Saturation Study (PDF), Prepared for California's Investor-Owned Utilities by RLW Analytics, August 2005)
Example 2: Water Heaters
If all California households with old, inefficient (0.58 EF) gas water heaters upgraded to energy-efficient models (0.62 EF), it would save 100 million Therms and 552,000 tons of CO2 per year (equivalent to taking 100,000 cars off the road).
Sources and Assumptions
- 12 million households in California (U.S. Census, April 2007)
- 12 lbs CO2 per Therm (California Climate Action Registry, April 2007)
- 12,100 lbs of CO2 per car per year (U.S. EPA Personal Emissions Calculator, April 2007)
- 13 Therms saved per water heater per year (FEMP savings calculator for water heaters using 50 gallons a day, 0.62 EF vs 0.58 EF)
- 65% of homes with 0.58 EF or lower (2005 California Statewide Residential Lighting and Appliance Efficiency Saturation Study (PDF), Prepared for California's Investor-Owned Utilities by RLW Analytics, August 2005)
Example 3: Dishwashers
If all California households with old, inefficient (0.485 EF) dishwashers upgraded to ENERGY STAR qualified models (0.65 EF), it would save 254 million Therms and 235,000 lbs of CO2 per year (equivalent to taking 42,700 cars off the road).
Sources and Assumptions
- 12 million households in California (U.S. Census, April 2007)
- 12 lbs CO2 per Therm (California Climate Action Registry, April 2007)
- 805 lbs CO2 per megawatt-hour (California Climate Action Registry, April 2007)
- 12,100 lbs of CO2 per car per year (U.S. EPA Personal Emissions Calculator, April 2007)
- 59.6% of homes with average 0.495 EF or lower (2005 California Statewide Residential Lighting and Appliance Efficiency Saturation Study (PDF), Prepared for California's Investor-Owned Utilities by RLW Analytics, August 2005)
- 4.1 Therms and 26.2 kWh saved per water heater per year (ENERGY STAR dishwasher savings calculator, 0.65 EF vs 0.495 EF)
Example 4: Clothes washer
If all California households with old, inefficient clothes washers upgraded to ENERGY STAR qualified models, it would save 7.8 million Therms, 50 million kilowatt-hours (kWh) and 61,000 tons of CO2 per year (equivalent to taking 11,000 cars off the road).
Sources and Assumptions
- 12 million households in California (U.S. Census, April 2007)
- 12 lbs CO2 per Therm (California Climate Action Registry, April 2007)
- 805 lbs CO2 per megawatt-hour (California Climate Action Registry, April 2007)
- 12,100 lbs of CO2 per car per year (U.S. EPA Personal Emissions Calculator, April 2007)
- 82.1% dishwasher saturation rate statewide (2005 California Statewide Residential Lighting and Appliance Efficiency Saturation Study (PDF), Prepared for California's Investor-Owned Utilities by RLW Analytics, August 2005)
- 18.8% of homes with dishwashers 10 years or older (2005 California Statewide Residential Lighting and Appliance Efficiency Saturation Study (PDF), Prepared for California's Investor-Owned Utilities by RLW Analytics, August 2005)
- 90% of homes with gas water heating (2005 California Statewide Residential Lighting and Appliance Efficiency Saturation Study (PDF), Prepared for California's Investor-Owned Utilities by RLW Analytics, August 2005)
- 4.7 Therms and 30 kWh saved per water heater per year (ENERGY STAR clothes washer savings calculator)