Green Quick Facts

List of Quick Green Facts and Carbon Footprint Information

Green Quick Facts is a List of Environmental Information to Astound You into Going Green. The following green quick facts and carbon footprint information sources were provided by Environmental Defense to show how the actions you take can reduce carbon emissions.

Statistics and Averages Used for All Calculations:

• The U.S. national average emissions rate is 0.668 short tons of CO2 per MWh (source PDF).


• The average price of electricity in 2006 was 10.4 cents/kWh (source; note that state prices vary widely).


• Burning natural gas produces 116.38 pounds CO2 per 10^6 Btu (source).


• The average price of residential natural gas in 2006 was $13.76 per thousand cubic feet (source).


• Residential energy use: 4.0 tons/person. According to the U.S. Environmental Protection Agency's latest inventory of national greenhouse gas emissions (PDF source), CO2 emissions from residential energy use averaged 4.0 tons CO2 per person in 2005, assuming a U.S. population of 300 million Americans.


• Personal vehicle use: 3.8 tons/person. Also according to the EPA inventory, personal vehicle use accounted for 3.8 tons CO2 per person, assuming a U.S. population of 300 million Americans.


• Personal flying: 1. 64 tons/person. The Bureau of Transportation Statistics provides information on jet fuel consumed in 2005 (source).


• Total personal CO2 emissions: 9.44 tons/person. Specific Calculations:


• Switch 3 lights to compact fluorescent lights -- CFLs use approximately 75% less energy than incandescent lights. The emissions savings are based on the assumption that you are replacing 3, 75-watt bulbs that are operated 4 hours a day, 365 days a year.


• Replace a porch light with a CFL -- CFLs use approximately 75% less energy than incandescent lights. The emissions savings are based on the assumption that you are replacing one, 75-watt bulb that is operated 24 hours a day, 365 days a year.


• Turn your thermostat down 2 degrees / AC up 2 degrees -- U.S. households consume 183 billion kWh for air conditioning (1,710 kWh/year per household). Approximately 57% of U.S. households use natural gas as the main fuel for space heating. About 30% use electricity. The remainder use fuel oil, kerosene or LPG and are not considered here.


• Households using electricity for space heating consume 3,524 kWh/year for space heating. Households using natural gas consume 55.4 million Btu/year for space heating. This means that households with electric heating use a total of 5,234 kWh/year for heating and cooling (3.5 tons CO2 emitted). Households with natural gas heating use 1,710 kWh/year for cooling and 55.4 million Btu/year for heating (total 4.4 tons CO2).


• Adjusting your thermostat 2 degrees (up in summer, down in winter) can save 4%.


• Programmable thermostat / AC -- U.S. households consume 183 billion kWh for air conditioning (1,710 kWh/year per household). Approximately 57% of U.S. households use natural gas as the main fuel for space heating. About 30% use electricity. The remainder use fuel oil, kerosene or LPG and are not considered here.


• Households using electricity for space heating consume 3,524 kWh/year for space heating. Households using natural gas consume 55.4 million Btu/year for space heating. This means that households with electric heating use a total of 5,234 kWh/year for heating and cooling (3.5 tons CO2 emitted). Households with natural gas heating use 1,710 kWh/year for cooling and 55.4 million Btu/year for heating (total 4.4 tons CO2).


• Installing a programmable thermostat can save as much as 10%.


• Insulate your home -- U.S. households consume 183 billion kWh for air conditioning (1,710 kWh/year per household). Approximately 57% of U.S. households use natural gas as the main fuel for space heating. About 30% use electricity. The remainder use fuel oil, kerosene or LPG and are not considered here.


• Households using electricity for space heating consume 3,524 kWh/year for space heating. Households using natural gas consume 55.4 million Btu/year for space heating.


• This means that households with electric heating use a total of 5,234 kWh/year for heating and cooling (3.5 tons CO2 emitted). Households with natural gas heating use 1,710 kWh/year for cooling and 55.4 million Btu/year for heating (total 4.4 tons CO2).


• Installing insulation and sealing leaks can save as much as 10%.


• Air dry your clothes -- The U.S. uses 66 billion kWh per year to dry clothes. Air drying rather than machine drying laundry three months every year would save 25% of this energy.


• Note that some households have gas-heated dryers instead of electric machines. For the purposes of this estimate, CO2 savings is based on 107 million households.


• Set your water heater to 120¬?F -- Approximately 40% of U.S. households use electricity for water heating. Households with electric water heaters use 2,552 kWh/year for water heating.


• Approximately 54% of U.S. households use natural gas for water heating. The average U.S. household uses 19,000 cf natural gas per year (19.7 million Btu).


• There is 3-5% energy savings for each 10 degrees decrease. The typical default setting on a water heater is 140 degrees. Environmental Defense assumes a conservative savings of 3% per 10 degrees -- thus 6% savings for a 20 degree decrease.


• Energy Star refrigerator -- Energy Star refrigerators use, on average, 40% less energy than traditional models. The average American household uses 1,462 kWh per year on refrigeration.


• Energy Star TV -- Energy Star televisions use 30% less energy than traditional models. The average American household consumes 308 kWh per year for TV use (with 107 million households).


• Energy Star dishwasher -- Energy Star dishwashers use about 41% less energy than traditional models. Dishwashers in the average American household use approximately 271 kWh per year (with 107 million households).


• Energy Star computer, monitor, and printer -- Energy Star computers, monitors, and printers use about 75%, 85%, and 60% less energy, respectively, than traditional models. The average American household uses about 215 kWh per year on computer use (with 107 million households). For this calculation, Environmental Defense assumes energy savings of 75% for replacing all three appliances.


• Energy Star clothes washer -- Energy Star washing machines use, on average, 50% less energy than traditional models. The average household consumes 93 kWh per year to run a washing machine (with 107 million households).


• On-demand "tankless" water heater -- Approximately 54% of U.S. households use natural gas for water heating (PDF). These households consume 19,000 cf natural gas per year (19.7 million Btu) for water heating (PDF).


• Replacing a standard tank natural gas water heater with on-demand heating can save up to 30%.


• Solar water heater -- Approximately 40% of U.S. households use electricity for water heating (PDF). Households with electric water heaters use 2,552 kWh/year for water heating (PDF).


• Low-flow faucets -- Approximately 40% of U.S. households use electricity for water heating (PDF). Households with electric water heaters use 2,552 kWh/year for water heating (PDF).


• Old faucets have flow rates of 3-7 gallons/minute (gpm) (PDF). For the purposes of this estimate, Environmental Defense uses 4 gpm for old faucets and showerheads. Aerated faucets can have flow rates as low as 0.5 gpm in bathroom sinks and up to 2.2 gpm in kitchen sinks. For the purposes of this estimate, Environmental Defense uses 2 gpm overall for aerated faucets (no data are available on the percentage of faucet use in the kitchen vs. the bathroom).


• According to Koomey et. al. (1994) (PDF), the average U.S. household uses 59.5 gallons of hot water per day, of which 4.6 are used for faucet flow (i.e., 7.7% of all hot water). Replacing old faucets with efficient ones cuts this hot water use in half. Environmental Defense assumes that the percentage savings on energy use is the same as savings from reducing hot water consumption.


• Low-flow showerheads -- Approximately 40% of U.S. households use electricity for water heating (PDF). Households with electric water heaters use 2,552 kWh/year for water heating (PDF).


• Approximately 54% of U.S. households use natural gas for water heating (PDF). The average U.S. household uses 19,000 cf natural gas per year (19.7 million Btu) (PDF).


• Old showerheads can have flow rates between 5 and 8 gpm. For the purposes of this estimate, Environmental Defense uses 5 gpm as flow rate for standard showerhead. Low-flow showerheads use 2.5 gpm.


• According to Koomey et. al. (1994) (PDF), the average U.S. household uses 59.5 gallons of hot water per day, of which 26 are used for showering (i.e., 43.7% of all hot water). Replacing old showerheads with efficient ones cuts this hot water use in half. Environmental Defense assumes that the percentage savings on energy use is the same as savings from reducing hot water consumption.


• Eat meatless -- The CO2 savings calculations are based on G Eshel and PA Martin, Diet, energy, and global warming. Earth Interactions 10, Paper No. 9 (2006): 1-17.


• All emissions savings are relative to an average American diet (according to data from the UN, 3,774 calories of food are produced per American per day, with 27.7% calories from animal-based products, of which 54% are meats, 41% dairy and 5% eggs). In this diet Americans eat, on average, 199 calories per day from chicken, 209 from pork and 119 from beef.


• The one meal with no meat diet assumes that every American eats 350 fewer calories from meat each week (this is about one-third the average daily meat intake, or one meal worth of meat). For the one meal with no meat and one day with no meat, avoided calories from assorted meats are in the same proportions as they are consumed in the mean American diet. In all diets, dairy and egg intake remains unchanged and calories from meat are replaced with calories from plant-based foods.
  
  The emissions savings from these dietary choices are calculated assuming that the meat not consumed by Americans is also not consumed by others outside the U.S., and thus results in a decrease in overall meat production. To the extent that American consumption were replaced by foreign consumption, the overall GHG emission reductions estimated here would be smaller on a global scale.


• CO2 emissions are based on previously published values of the amount of fossil fuel used (and thus the amount of CO2 emitted) to produce different types of foods. Non-CO2 emissions (given as .CO2 equivalents.) from animal-based foods (eggs, dairy, and various meats) are based on data from the U.S. Department of Energy. Only methane and nitrous oxide from animal digestion and manure management are considered. The calculation assumes there are no non-CO2 emissions from crop production.


• Recycled paper -- For this calculation, Environmental Defense assumes that 500 sheets of paper weigh approximately 5 pounds. Environmental impact estimates were made using the Environmental Defense Paper Calculator.


• Recycle steel ("tin") cans -- The average U.S. household uses 90 lbs of steel cans each year. Recycling this saves 144 kWh.


• Recycle aluminum cans -- Recycling one aluminum can saves 0.35 kWh. Americans use 200 million aluminum cans per day.


• Recycle glass bottles -- Recycling one glass bottle saves 0.4 kWh. The average U.S. household uses about 383 containers per year.


• Drive less aggressively -- EPA's latest regulation on fuel economy labeling (PDF) suggests that highway and city driving is a 57/43 split; assuming that potential fuel economy improvement is half of the maximum improvement suggested in the fuel economy.gov, Environmental Defense estimates that potential fuel economy improvement is 10.5 percent.
  
  The emissions savings are based on a vehicle with a fuel economy of 19.6 mpg being driven 11,900 miles a year and emitting 25.3371 pounds of CO2 per gallon of gasoline consumed. Cost savings based on an average price of motor gasoline (all grade) in 2006 of $2.33, including taxes (Energy Information Administration, March 2007 Monthly Energy Review, Table 9.4, accessed on March 27, 2007).


• Drive the speed limit -- Reducing speed from 70 mph to 65 mph results in a 9% improvement in fuel efficiency (XLS). Cost savings based on an average price of motor gasoline (all grade) in 2006 of $2.33, including taxes (Energy Information Administration, March 2007 Monthly Energy Review, Table 9.4, accessed on March 27, 2007).


• Keep your car tires inflated -- Under-inflated tires can lower gas mileage by 0.4 percent for every 1 psi drop in pressure of all four tires. The emissions savings are based on a 3.3% increase in fuel efficiency. Cost savings based on an average price of motor gasoline (all grade) in 2006 of $2.33, including taxes (Energy Information Administration, March 2007 Monthly Energy Review, Table 9.4, accessed on March 27, 2007).


• Drive 10 miles less -- Driving 10 miles less each week, or 520 miles less each year would reduce the average miles driven from 11,900 to 11,320. The emissions savings are calculated assuming the vehicle has a fuel economy of 19.6 mpg and emits 25.3371 pounds of CO2 per gallon of gasoline consumed. Cost savings based on an average price of motor gasoline (all grade) in 2006 of $2.33, including taxes (Energy Information Administration, March 2007 Monthly Energy Review, Table 9.4, accessed on March 27, 2007).


• Carpool or take public transit to work -- The average commute in the U.S. is 30 miles. Assuming the reduction occurs for 50 weeks, annual driving would drop from 11,900 to 10,400. The emissions savings are calculated assuming the vehicle has a fuel economy of 19.6 mpg and emits 25.3371 pounds of CO2 per gallon of gasoline consumed. Cost savings based on an average price of motor gasoline (all grade) in 2006 of $2.33, including taxes (Energy Information Administration, March 2007 Monthly Energy Review, Table 9.4, accessed on March 27, 2007).


• Buy a hybrid or car that's 10% more efficient -- To calculate savings, Environmental Defense assumes you are replacing a vehicle that has a fuel economy of 19.6 mpg (the average U.S. car) with one that gets 21.56 mpg. Environmental Defense also assumes that you drive 11,900 miles each year and emit 25.3371 pounds of CO2 per gallon of gasoline consumed. Cost savings based on an average price of motor gasoline (all grade) in 2006 of $2.33, including taxes (Energy Information Administration, March 2007 Monthly Energy Review, Table 9.4, accessed on March 27, 2007).


• Fly less -- A domestic flight originating in the U.S. averages approximately 42 passenger-miles per gallon and international flights average 21 passenger-miles per gallon, according to the Bureau of Transportation Statistics.


• Burning a gallon of jet fuel produces 21.1 lbs of CO2 (U.S. Department of Energy and the Energy Information Administration, Instructions for Form EIA 1605B, Voluntary Reporting of Greenhouse Gas Emissions, Appendix B). In addition, according to the Climate Neutral Network, non- CO2 greenhouse gas emissions from air travel are at least as significant as the CO2 impacts (doubling the emissions as expressed in CO2-equivalents) and upstream processes add an additional 8 percent. Based on this information, aviation was responsible for approximately 1.8 tons CO2-equivalents per person in 2005, assuming a U.S. population of 300 million Americans.

The preceding was taken from http://green.yahoo.com/pledge/

*Not all links to Source information were translated into this version, as the main source is cited above. Please consult the page above for specifics on many of the percentages and numbers quoted within the document that do not have supporting documentation and/or evidence, namely in places where PDF, XLS, etc., follow information in parentheses. Our version is merely for basic informational purposes.