# Our Assumptions

## Basic Assumptions:

For every kilowatt-hour (kWh) of energy consumed, 1.6 pounds of carbon dioxide are released into the atmosphere. For every therm, 11.7 pounds or carbon dioxide are released into the atmosphere.

The average price for electricity is $0.106 per kWh and the average price for natural gas is $1.21 per therm.

For every gallon of gasoline consumed, 20 pounds of carbon dioxide are released into the atmosphere.

All Energy Star appliance calculations assume average Energy Star models, average conventional models, and average appliance usage.

## Change Your Light Bulbs

### I have replaced __ 60-watt standard light bulbs with **13-watt**
CFL bulbs

### I have replaced __ 75-watt standard light bulbs with **20-watt**
CFL bulbs

### I have replaced __ 100-watt standard light bulbs with 23-watt CFL bulbs

Over the course of its lifetime, a 13-watt compact fluorescent
light bulb (CFL) will emit 752 pounds of CO_{2} less than
a standard 60-watt incandescent light bulb, a 20-watt CFL will
emit 880 pounds of CO_{2} less than a standard 75-watt
light bulb, and a 23-watt CFL will emit 1232 pounds of
CO_{2} less than a standard 100-watt light bulb. These
calculations assume the replacement of a 1,000-hour standard light
bulb with a 10,000-hour CFL. Also assumes is that for every kWh
of energy consumed, 1.6 pounds of carbon dioxide are released into
the atmosphere.

Source: Energy Star "Compact Fluorescent Light Bulbs Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

## Plant Trees

### I have planted __ trees

Over the course of its 40-year lifetime the average tree can
absorb around one ton of CO_{2}.

Source: www.climatecrisis.org

### I have saved __ acres of tropical rainforest

The slashing and burning of one acre of rainforest releases 80
tons of CO_{2} into the atmosphere.

Source:www.stanford.edu/dept/news/pr/00/forests67.html

## Buy ENERGY STAR Appliances

### I have purchased an ENERGY STAR refrigerator

Over the course of the average Energy Star rated refrigerator's
13-year lifespan, it will emit 1,661 pounds of CO_{2} less
than an average conventional model. This calculation assumes that
you are choosing to install an Energy Star refrigerator with a top
mount freezer into your home instead of a conventional model and
that for every kWh of energy consumed, 1.6 pounds of carbon
dioxide are released into the atmosphere.

Source: Energy Star "Residential Refrigerator Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I have purchased an ENERGY STAR dishwasher and have an electric water heater

### I have purchased an ENERGY STAR dishwasher and have a natural gas water heater

Assuming that the average lifespan of a dishwasher is 10 years,
that 1.6 pounds of carbon dioxide are emitted for every kWh of
energy consumed, and that the average household runs four loads of
dishes each week, an Energy Star rated dishwasher that utilizes an
electric water heater saves an average of 1,155 lbs of
CO_{2} over the course of its lifetime. The average
Energy Star rated dishwasher that utilizes a natural gas powered
water heater saves an average of 508 lbs of CO_{2} over
the course of its lifetime.

Source: Energy Star "Residential Dishwasher Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I have purchased an ENERGY STAR washing machine and have an electric water heater

### I have purchased an ENERGY STAR washing machine and have a natural gas water heater

Assuming that the lifespan of an average washing machine is 11
years, that 1.6 pounds of carbon dioxide are emitted for every kWh
of energy consumed, and that the average household runs four loads
of wash each week, an Energy Star rated washing machine that
utilizes an electric water heater saves an average of 2,672 lbs of
CO_{2} over the course of its lifetime. An Energy Star
rated washing machine that utilizes a natural gas powered water
heater saves an average of 504 lbs of CO_{2} over the
course of its lifetime.

Source: Energy Star "Residential Dishwasher Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I have purchased an ENERGY STAR oil-fired furnace

### I have purchased an ENERGY STAR natural gas-fired furnace

During its 17-year lifespan, an average Energy Star rated oil
furnace will emit approximately 65,513 pounds of CO_{2}
less than an average conventional unit. During the 18-year
lifespan of an average Energy Star gas-fired furnace, it will emit
55,698 pounds of CO_{2} less than an average conventional
unit. This calculation assumes that you are replacing the furnace
of a 2,500 square foot home located in one of the Mid-Atlantic
States with a new Energy Star furnace that uses a programmable
thermostat. Also assumed is that 159.5 pounds of carbon dioxide
are emitted for every million British Thermal Units (MMBtu) of oil
consumed and that 116.3 pounds of carbon dioxide are emitted for
every MMBtu of gas consumed.

Source: Energy Star "Residential Furnace Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I have purchased an ENERGY STAR oil-fired boiler

### I have purchased an ENERGY STAR natural gas-fired boiler

During its 20-year lifespan, an average Energy Star rated
oil-fired boiler will emit around 150,910 pounds of CO_{2}
less than an average conventional unit. During the 20-year
lifespan of an average Energy Star rated gas-fired boiler, it will
emit 110,036 pounds of CO_{2} less than an average
conventional unit. These calculations assume that the house is
located in a place with a climate similar to that in Washington DC
and that the new furnace uses a programmable thermostat. Also
assumed is that 159.5 pounds of carbon dioxide are emitted for
every MMBtu of oil consumed and that 116.3 pounds of carbon
dioxide are emitted for every MMBtu of gas consumed.

Source: Energy Star "Residential Boiler Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I have purchased __ ENERGY STAR air conditioner(s)

The average Energy Star rated air conditioner saves 2,195 lbs
of CO_{2} from being emitted over its 11-year lifecycle.
This calculation assumes that an Energy Star model is used instead
of a conventional air conditioner, in average US climatic
conditions, and that 1.6 pounds of carbon dioxide are emitted for
every kWh of energy consumed.

Source: Energy Star "Residential Room Air Conditioner Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I have purchased __ ENERGY STAR desktop computer(s) and monitor(s)

Using an Energy Star rated desktop computer and monitor can
reduce CO_{2} emissions by 1,274 lbs over their 4-year
lifespan. Most of the savings—1,154 pounds
CO_{2}—come from the monitor. These calculations
assume the replacement of an average conventional computer with a
17" monitor with an average Energy Star rated computer with a 17"
LCD monitor. Also assumed is that 1.6 pounds of carbon dioxide
are emitted for every kWh of energy consumed.

Source: Energy Star "Computer and Monitor Savings Calculators" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I have purchased __ ENERGY STAR television(s)

Over the 9-year lifetime of an average Energy Star rated
television, it produces 619 pounds of CO_{2} less than an
average conventional unit. This calculation assumes that 1.6
pounds of carbon dioxide are emitted for every kWh of energy
consumed.

Source: Energy Star "Television Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

## Conserve Energy

### I will adjust my thermostat down __ °F in the winter

### I will adjust my thermostat up __ °F in the summer

Adjusting your thermostat down in the winter or up in the
summer will reduce CO_{2} emissions by 500 pounds a year
for each degree.

Source: www.climatecrisis.org

### I will keep my computer off for __hours per day

This calculation assumes that each hour pledged will be adhered to every day of the year. Calculation is for a desktop computer with a 17" monitor that is used an average of 250 days a year. Also assumed is that 1.6 pounds of carbon dioxide are emitted for every kWh of energy consumed.

Source: Energy Star "Computer and Monitor Savings Calculators" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I do not own a computer

If you do not own or use your own computer you can save
approximately 5,107 pounds of CO_{2} from being produced.
This calculation assumes average computer usage and a 4-year
lifespan for a desktop computer with 17" regular monitor. Also
assumed is that 1.6 pounds of carbon dioxide are emitted for every
kWh of energy consumed.

Source: Energy Star "Computer and Monitor Savings Calculators" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I do not own a TV

If you do not have a TV in your home you can save approximately
2,700 pounds of CO_{2} from being produced. This
calculation assumes a 9-year lifespan for a TV and that the
average TV in the United States is on for 5.5 hours a day. Also
assumed is that 1.6 pounds of carbon dioxide are emitted for every
kWh of energy consumed.

Source: Energy Star "Television Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

### I do not own an air conditioner

If you do not use an air conditioner in your home you can save
approximately 23,707 pounds of CO_{2} from being produced
over its 11-year lifespan. Assumes a location with a climate
similar to that of Washington DC. Also assumed is that 1.6 pounds
of carbon dioxide are emitted for every kWh of energy
consumed.

Source: Energy Star "Residential Room Air Conditioner Savings Calculator" at www.energystar.gov/index.cfm?c=bulk_purchasing.bus_purchasing

## Use Hot Water Efficiently

### I have turned down my hot water heater to 120 degrees

If you turn your hot water heater down to 120 degrees you can
save 8,250 pounds of CO_{2} over its 15-year lifespan.

Source: www.climatecrisis.org

### I have wrapped my water heater in insulation

If you wrap your hot water heater in an insulating blanket you
can save 15,000 pounds of CO_{2} from being produced over is 15-year
lifespan.

Source: www.climatecrisis.org

### I have installed a low-flow showerhead

By installing a low-flow showerhead and reducing the amount of
hot water being produced, you can save 2,450 pounds of
CO_{2} from being produced over the showerhead's 7-year
lifespan.

Source: www.climatecrisis.org

### I have installed low-low sink heads or faucet aerators

By installing low-flow sink heads or faucet aerators and
reducing the amount of hot water being produced, you can save
3,150 pounds of CO_{2} from being produced over their
7-year lifespan.

Source:www.newdream.org/cnad/user/ttt_detail.php?config[r55][instance_uid]=8

### I will wash my clothes with cold or warm water instead of hot

By washing clothes in cold or warm water instead of hot, 500
pounds of CO_{2} can be saved each year. Assumes 2 loads
of wash completed each week.

Source: www.enviroliteracy.org/article.php/1345.html

## Buy Clean Energy

### I have purchased renewable energy for __% of my electric bill

Assumes the purchase of wind or solar generated power and no
direct CO_{2} emissions associated with the purchase of
this renewable energy. The renewable energy purchased for this
action can be from a utility offering energy from renewable power
sources or through the purchase of renewable energy credits.

### I have installed a solar or wind power system that provides __% of my electricity

Assumes no direct CO_{2} emissions associated with the
use of wind and solar power.

## Drive Less—Drive Smart

### I will take public transportation __ days per week

Assumes that taking public transportation cuts
CO_{2} emissions by 90%. Also assumes the average person
commutes 50 weeks per year, that 20 pounds of
CO_{2} are emitted for every gallon of gasoline consumed,
and that the mileage for the car not driven is 22 miles per
gallon.

### I will walk or bike __ days per week

Assumes no direct CO_{2} emissions associated with
walking or biking. Also assumes the average person commutes 50
weeks per year, that 20 pounds of CO_{2} are emitted
for every gallon of gasoline consumed, and that the mileage for the
car not driven is 22 miles per gallon.

### I will carpool or carshare __ days per week

Assumes sharing a ride with one other person, that the
average person commutes 50 weeks per year, that 20 pounds of
CO_{2} are emitted for every gallon of gasoline
consumed, and that the mileage for the car not driven is 22 miles
per gallon. Also assumes that the weight of one extra person
in the car does not increase the amount of gasoline consumed.

### I will telecommute from a home office __ days per week

Assumes no additional CO_{2} emissions associated with
telecommuting from home. Also assumes the average person
commutes 50 weeks per year, that 20 pounds of
CO_{2} are emitted for every gallon of gasoline consumed,
and that the mileage for the car not driven is 22 miles per
gallon.

### I will keep my car properly tuned

Keeping your car properly tuned reduces CO_{2}
emissions by an average of 545 pounds a year. This calculation
assumes that the average car is driven 12,000 miles a year and has
a fuel efficiency of 22 mpg; an average of 20 pounds of
CO_{2} are produced per gallon of gasoline consumed; and,
there is a 5% reduction in gas use as a result of keeping the car
tuned.

Sources: www.enviroliteracy.org/article.php/1345.html; www.epa.gov/otaq/climate/420f05004.htm

### I will ensure there is sufficient tire pressure in cars I drive

Ensuring that there is sufficient pressure in car tires reduces
CO_{2} emissions by an average of 327 pounds a year. This
calculation assumes that the average car is driven 12,000 miles a
year and has a fuel efficiency of 22 mpg; an average of 20 pounds
of CO_{2} are produced per gallon of gasoline consumed;
and, CO_{2} emissions from driving are reduced by 3% as a
result of keeping tires properly inflated.

Sources: www.climatecrisis.org; www.epa.gov/otaq/climate/420f05004.htm

### I have replaced my gasoline powered car with a hybrid

This calculation assumes that average car is driven 12,000 miles a
year, that an average of 20 pounds of CO_{2} are produced
per gallon of gasoline consumed and that the average new car is
owned for 4 years before it is traded in for a new one. Also
assumed is that the average small car has a fuel efficiency of 30
mpg, the average mid-sized car has a fuel efficiency of 23 mpg,
and the average large car or SUV has a fuel efficiency of 18 mpg.
Hybrid mileages come from www.greenhybrid.com.

Sources: www.epa.gov/otaq/climate/420f05004.htm; www.greenhybrid.com

## Eat Green

### I will eat a vegetarian diet __ days a week

According to Gidon Eschel and Pamela A. Martin of the University
of Chicago, a person with a red meat diet emits the global warming
equivalent of 2.52 tons of CO_{2} a year more than a
person with a vegetarian diet. For each day a week you eat on a
vegetarian diet, you save 718 lbs of CO_{2} a year. It is
assumed that the portion of animal-based calories in the diet is
26%.

Source: geosci.uchicago.edu/~gidon/papers/nutri/nutriEI.pdf

### I will eat only locally-produced food __ days a week

According to www.climatecrisis.org, the average meal in the United States travels 1,200 miles from the farm to your plate. The average local meal travels 200 miles. If a truck travels just 10 miles per gallon of gasoline, it requires 100 gallons of fuel to transport food the excess distance.

Source: www.climatecrisis.org

### I will eat organic food __ days per week

For every day of the week that you eat only organically produced
food, you save 572 pounds of CO_{2} from being emitted
each year.

Source: www.stopglobalwarming.org/carboncalculator.asp?c=5

## Reduce Waste—Support Recycling

### I now buy recycled paper with __% post-consumer waste content

Switching to using only 100% post consumer recycled paper reduces
CO_{2} emissions by 288 pounds per year. This calculation
assumes that the average per capita paper consumption in the
United States is 273 pounds per year and that one ton of paper
with a post consumer recycled content of 100% emits 2,108 less
pounds of CO_{2} equivalent than non-recycled paper.

Source: Environmental impact estimates were made using the Environmental Defense Paper Calculator. For more information visit www.papercalculator.org.

### I will recycle all my white and mixed paper

For every pound of paper that is recycled, CO_{2}
emissions are reduced by 4 pounds. This calculation assumes a
yearly per capita paper consumption of 273 pounds and a 100%
recycling rate.

Sources: www.enviroliteracy.org/article.php/1345.html

### I will recycle all my newspaper

Recycling 100% of your newspaper waste can reduce your annual
CO_{2} emissions by 184 pounds. This calculation assumes
a 100% newspaper recycling rate and average waste generation; it
also takes into account the CO_{2} produced throughout the
paper's lifecycle.

Source: epa.gov/climatechange/wycd/calculator/ind_calculator.html

### I will recycle all my aluminum and steel cans

Recycling 100% of your aluminum and steel cans can reduce your
annual CO_{2} emissions by 166 pounds. This calculation
assumes a 100% recycling rate and average waste generation; it
also takes into account the CO_{2} produced throughout the
metal's lifecycle.

Source: epa.gov/climatechange/wycd/calculator/ind_calculator.html

### I have reduced my garbage by 10% by buying products with less packaging and carrying my own shopping bags

Reducing your garbage by 10% can save 1,200 lbs of CO_{2}
from being released into the atmosphere. An additional 17 pounds
of CO_{2} can be saved each year by bringing your own bags
to the grocery store.

Source: www.climatecrisis.org; www.seattleu.edu/sustainability/gi_be_waste.asp

### I have reduced the amount of junk mail that I receive by taking myself off of mailing lists

The amount of resources and energy it takes to produce the 5.2
million tons of bulk mail sent out in the United States each year
result in the production of 92 pounds of CO_{2} per person
annually.

Source: www.newdream.org/cnad/user/ttt_detail.php?config[r55][instance_uid]=4

## Offset Your Emissions

### I have offset __ miles of my car travel

Assumes average vehicle mileage of 22 miles per gallon and the release of 20 pounds of carbon dioxide per gallon of gasoline consumed.

### I have offset __ miles of my air travel

Assumes CO_{2} emissions of 0.417 pounds per mile flown.

Source: www.carbonfund.org