Fill in Excel spreadsheet/ answer 4 questions

&CPage &P of &N, &F, Ecological Footprint of Households, by Mathis Wackernagel, Ritik Dholakia, Diana Deumling and Dick Richardson, Redefining Progress, printed on &D

With the exception of the sub-categories 'Eating Out' and 'Garden Area,' all sub-categories in the FOOD section should include only food being brought into the household from an outside source (i.e., not homegrown food).

include canned and other prepared fruits and vegetables

Register the entire lot size, including the space the building sits on. If the lot is shared by a number of households (such as in apartment buildings), divide the lot area by the number of households. True wilderness areas which are preserved forever and which are part of the property are not counted as an additional footprint. These spaces are considered to be a biodiversity area in service of humanity as a whole.

For composition of electricity: Your local electricity provider should be able to give you a breakdown of the composition of electricity generation for your electricity use (usually this information is sent with your electricity bill). For instance, the following breakdown is the "1999 California Power Mix" provided by Pacific Gas and Electric: 67% coal, nat. gas and nuclear (thermal) 20% large hydroelectric (low-altitude) 3% small hydroelectric (high-altitude) 2% wind 1% solar 2% biomass 5% geothermal

In this row you should enter not just cotton clothing, but all cotton textile and other products.

In this row you should enter not just wool clothing, but all wool textile and other products.

In this row you should enter not just synthetic fiber clothing, but all synthetic fiber textile and other products.

This line includes all long-lasting paper and hygenic paper that is not recycled. All paper that could be recycled is counted in the waste section. This recycled paper includes free and paid-for newspapers, the mail and advertising you receive, household paper, wrapping paper etc.

This line only covers the transportation energy of mail. The paper content is accounted for separately in the paper line. Note: count only all the mail you send out or all the mail you receive, otherwise it leads to double counting.

The laundry in the household is already accounted for through the energy use of the household, the detergents purchased and through the water use (which is not accounted for in this spread sheet). Counting all laundry here would lead to double counting.

Enter your recycling % in H125

See note with paper products. Account only once for the paper: either on the incoming side or on the waste side.

Attention! The cells in this block need to be copied onto themselves as values rather than formulas for the household calcuation sheet. The Correction factors calibrate this household footprint spreadsheet with the overall US average Footprint spreadsheet, so that the "average" footprints are equal using both assessment methods. The first term in each equation represents the square meters required for that sector of consumption in that land use category.

A standard bottle of wine contains 0.75 liters or 0.75/1.06 = 0.7 quarts

There are 1.1 Therms per CCF. CCF are one hundred cubic feet. Check over how many days (or months) you are billed. For example, if the bill stretches over 40 days, divide the amount by 40 and multiply by 30 to get the monthly amount. If you receive the bill bi-monthly, just divide the amount by two. Note that gas consumption varies considerably with the season.

A cord of wood is 80 cubic feet (roughly 3 x 4 x 7 feet), and contains roughly 3000 pounds of dry wood.

"Person-miles" = vehicle miles x number of household members in the vehicle.

Enter the miles that you drove someone else's car or that you rode in someone else's car, if you were not driving. If some of these miles involved carpooling with non-household members, then only enter the mileage that can be allocated to you and other household members.

If some of these miles involved carpooling with non-household members, then only enter the mileage that can be allocated to you and other household members.

"Person-hours" = hours of flying x number of household members on the flight.

Average US per-capita food consumption data, unless otherwise noted, is for 1997 and taken directly from: Food Consumption, Prices, and Expenditures, 1970-97, USDA Economic Research Service (ERS), http://usda.mannlib.cornell.edu/, Tables 1-41: Per Capita Food Consumption, 1970-97

Per-capita average consumption of veggies, potatoes and fruit: 48.7 lbs/month

Per-capita average consumption of bread: 7.8 lbs/month

Per-capita average consumption of rice, cereals, noodles: 8.9 lbs/month

Per-capita average consumption of beans: 0.7 lbs/month

Per-capita average consumption of milk, cream, yogurt, sour cream: 9.1 qts/month

Per-capita average consumption of ice cream: 1.2 quarts per month

Per-capita average consumption of cheese, butter: 2.7 lbs/month

Per-capita average consumption of eggs: 20 eggs/month

Per-capita average consumption of pork: 3.8 lbs/month

Per-capita average consumption of chicken, turkey: 5.4 lbs/month

Per-capita average consumption of beef (pasture and grain): 5.4 lbs/month

Per-capita average consumption of fish: 1.2 lbs/month

Per-capita average consumption of sugar: 5.5 lbs/month

Per-capita average consumption of solid veg. fats: 2.5 lbs/month

Per-capita average consumption of liquid vegetable oils: 1.2 qts/month

Per-capita average consumption of tea & coffee: 0.8 lbs/month

Per-capita average consumption of juice & wine: 3.0 quarts/month

Per-capita average consumption of beer: 7.3 quarts/month

Per-capita average garden area: no data

Per-capita spending on food and drink consumed outside the house: estimated to be $68 per month

Per-capita average housing unit size: 1525 sq/ft @ 2.62 people per house =582 sq. ft./person

Per-capita lot size: Median single detached house lot size = 0.35 acres, or 15246 sq. ft. Average household size : 2.62 Square feet/person: 5819 However, this only accounts for single detached houses, and would need to be adjusted downward slightly to account for apartments and smaller units.

Per-capita expenditure on Hotels, Motels, Camping: $464/hhld Hhld size = 2.6 = $15 /month

Per-capita electricity consumption: 323 kWh/capita/month

Per capita average breakdown of electricity generation in the US: Fossil-based and nuclear: 88% hydroelectric: 10% Other renewables: 2% (geothermal 0.4, wood 1.1, waste 0.6, wind 0.1, solar 0.03) The distribution will vary by region. Contact your electricity provider to find out your local electricity breakdown (see cell B56).

Per-capita natural gas consumption: 17.6 Therms/person/month

Average per-capita LPG consumption: 1.2 gallons/person/month

Average per-capita fuel oil consumption: 2.4 gallons/person/month

Average Per-Capita Water, sewer, garbage service: $9 per person per month

Average per-capita straw consumption: no data

Average per-capita firewood consumption: .08 cords/year, or 240 pounds

Average per-capita construction wood and furniture consumption: no data

If you are calculating the footprint for your whole household, be sure to enter all miles traveled and gas consumed by the household members. The transportation footprint is then divided equally among household members.

Per-capita transit bus use: 7 passenger-miles/person/month

Per-capita intercity bus use: 38 passenger-miles/person/month

Per-capita transit rail use: 7 passenger-miles/person/month

Per-capita Amtrak use: 2 passenger-miles/person/month

Per-capita taxi/ other car/ rental use: no data

Average US car fuel efficiency is 20 mpg.

Per-capita car use: 738 vehicle miles/person/ month

Average US car fuel efficiency is 20 mpg.

Per-capita parts for repair: 0.2 pounds/ person/ year (this figure includes only tires and batteries)

Per-capita air travel (with airlines) 0.4 passenger-hours/month/person

Average Per-Capita Consumption of cotton textiles: 1.3 lbs/month

Average Per-Capita Consumption of wool textiles: 0.1 lb/month

Average Per-Capita Consumption of synthetic textiles: 0.5 lb/month

Average Per-Capita Consumption of Durable Paper Products and Hygenic Paper Products: 3 lbs/month

Average Per-Capita Consumption of Tools and Metal Parts: 8 lbs/month

Average Per-Capita Consumption of Leather Products: 0.5 lb/month

Average Per-Capita Consumption of Plastic Products and Photos: 10 lbs/month

Average Per-Capita Consumption of Porcelain and Glass Products: 3 lbs/month

Average Per-Capita Consumption of Medicine: 2 lbs/month

Average Per-Capita Consumption of Hygiene Products and Cleaning Stuff: 2 lbs/month

Average Per-Capita Consumption of Cigarettes: 0.4 lbs/month

Average Per-Capita International Postal Services: 0.2 lbs/month

Average Per-Capita Domestic Postal Services: 4.0 lbs/month

Average per-capita dry cleaning and external laundry services: no data

Average Per-Capita Telephone service: $27 per person per month

Average Per-Capita Medical Insurance and services: $47 per person per month

Average Per-Capita Household Insurance: $27 per person per month

Average Per-Capita Entertainment (fees, admissions and services): $24 per person per month

Average Per-Capita Education Services: $20 per person per month

All data from USEPA, Characterization of Municipal Solid Waste in the United States, 1996, Table 1, "Materials Generated in the Municipal Waste Stream, " Pp. 28. For explanation of formula, see note in Paper Waste cell.

Per-Capita Paper Waste 21 lbs/person/month

Per-Capita Aluminum Waste 1 lbs/capita/month

Per-Capita Other Metal Waste 2 lbs/capita/month

Per-Capita Glass Waste 5 lbs/capita/month

Per-Capita Plastics Waste 5 lbs/capita/month

Enter in this column your monthly expenditure in each category

Unless otherwise noted, the Fossil Energy component of the household footprint follows this formula: (Carbon sequestration ratio) * (Energy intensity) * (Waste factor, if needed) * (Quantity in metric or US standard) * (Metric conversion factor, if needed) or (m^2/Gj) * (Gj/Kg) * (Kg) Other terms found in specific formulas are explained in cell notes.

see: "Estimating and Addressing America's Food Losses," Food Review, Jan-April 1997, USDA, ERS

Fossil energy footprint of eggs: 0.05 refers to 1 egg = 50g =.05 kg

Fossil energy footprint of liquid vegetable oil and fat: 0.8 = estimated density of vegetable oil (kg/l)

Fossil energy component of eating out: 10000/73000 = Carbon absorption factor (m^2/Mj) 8 Mj/$ spent on food eaten out (estimate)

The life-cycle embodied energy of a standard Canadian house with 350 square meters of living space adds up to 1'310 Gj (Canadian Mortgage and Housing Corporation, OPTIMIZE, 1991, researched by Sheltair). Life-expectancy of the house is 40 years.

The life-cycle embodied energy of a standard Canadian house with 350 square meters of living space adds up to 1'310 Gj (Canadian Mortgage and Housing Corporation, OPTIMIZE, 1991, researched by Sheltair). Life-expectancy of a brick building may be 70 years. The standard house is to a significant part a wood based construction. However, once redoing the calculation for a brick based construction, the embodied energy content comes to about the same.

Hotel energy costs are estimated from the average resource use of households. We assume an average wooden house in the US (with the land) would cost 150,000 dollars and has 2000 square feet. This corresponds to a monthly mortgage cost of 1000 dollars. In addition, each square foot may use the equivalent of 36 Mj of energy per year, including hot water and electricity, or 3 per month times 2000 square feet = 6000 Mj/month, or 6 Mj per dollar. Apart from the energy aspect, if you enter 1000 dollars a month, you should get the same result as a 2,000 square foot house. If you delete the second term in the energy column (which corresponds to the 6 Mj per dollar operational energy), the energy column also should be the same.

Fossil energy footprint of thermally produced electricity: 3.6 = energy intensity of production 0.3 = amount of energy transfer due to energy loss in conversion from the primary energy source to electricity (in generating and delivering electricity, 70% of the energy is lost). D58 = component of total electricity generated from thermal sources

World average growing forests can absorb per hectare the carbon of 96 Gj/yr of gas. Therefore, in this calculation: 10000/96000 gives the inverse of the carbon absorption capacity of world average forests in [m2*yr/Mj]. 29.3 gives kWh per Therm 3.6 gives Mj/kWh 1/0.3048^3/100 translates m3 into CCF Here's a second way of calculating it: 1 m3 of gas contains the energy of 8.905 Mcal corresponding to 4.184 more Mj.

The fossil gas footprint is 96 Gj per 10,000 m2 and year. One liter of LPG contains about 25 Mj.

For Fossil Energy Footprint of water, sewer, garbage service 12 Mj/$ = Estimated Energy Intensity

For Fossil Energy Component of Transit Bus Footprint: 10000/73000 = carbon absorption ratio 3.77 = Mj/Km including embodied energy (see Transport sheet)

For Fossil Energy Component of Intercity Bus Footprint: 10000/73000 = carbon absorption ratio 0.92 = Mj/Km including embodied energy (see Transport sheet)

For Fossil Energy Component of Transit Footprint: 10000/73000 = carbon absorption ratio 3.09 = Mj/Km including embodied energy (see Transport sheet)

For Fossil Energy Component of Transit Footprint: 10000/73000 = carbon absorption ratio 2.46= Mj/Km including embodied energy (see Transport sheet)

73000 Mj /10000 m2 and year is the conversion ratio for fossil fuel to get the area necesary for the CO2 absorption. 35 Mj/l is the energy content of fossil fuel. 1.5 corresponds to the indirect energy consumption of car use: 15 percent is additional energy to build the car. 35 percent is the indirect energy consumed to build the physical infrastructure needed for automobile use (highways, bridges, etc.). This figure is derived thus: 50% of embodied energy consumed by government expenditures is in physical infrastructure, or, 8% of total energy consumed in the US Economy (50% of the 15% that is government consumption). This 8% for "structural" energy consumption (of which we estimate 80% is due to personal automobile use) translates into an additional 35% indirect energy consumed for transport. For the calculation see sheet "Government Footprint Analysis".

73000 Mj /10000 m2 and year is the conversion ratio for fossil fuel to get the area necesary for the CO2 absorption. 35 Mj/l is the energy content of fossil fuel. 1.5 corresponds to the indirect energy consumption of car use: 15 percent is additional energy to build the car. 35 percent is the indirect energy consumed to build the physical infrastructure needed for automobile use (highways, bridges, etc.). This figure is derived thus: 50% of embodied energy consumed by government expenditures is in physical infrastructure, or, 8% of total energy consumed in the US Economy (50% of the 15% that is government consumption). This 8% for "structural" energy consumption (of which we estimate 80% is due to personal automobile use) translates into an additional 35% indirect energy consumed for transport. For the calculation see sheet "Government Footprint Analysis".

10000/73000 = carbon absorption ratio 100 = MJ/Kg parts, or the energy intensity of the parts

For Fossil Energy Component of Airplane Footprint: 10000/73000 = carbon absorption ratio 3.34 = MJ/Km, including embodied energy of airport infrastructure. (see Transport sheet) 800 = Km/hr

For Fossil Energy Component of Paper Products: 10000/73000= Carbon Absorption Factor 35 = Energy Intensity of Paper Products 0.6 = a factor representing the fact that 60 percent of paper consumed is by the household, and another 40% is released indirectly from the commercial stream due to household activities.

10000/73000 refers to 73 Gj/ha CO2 absorption for fossil fuel. 60 is the energy intensity in Mj/kg IF($H$9="m",1,0.454) translates kilograms into pounds

For Fossil Energy Footprint of Dry cleaning and laundry service 6 Mj/$ = Estimated Energy Intensity

For Fossil Energy Footprint of Telephone service 1 Mj/$ = Estimated Energy Intensity

For Fossil Energy Footprint of Medical Insurance and services: 4 Mj/$ = Estimated Energy Intensity

Assuming that half of the money goes to administration, and half insurance claims (rebuilding houses) the rebuilding houses figures are taken from the hotel category (excluding the operational energy part). Since rebuilding of houses does not include land prices, the resource intensity is doubled (assuming that half the cost of housing is land, and half is construction).

For Fossil Energy Footprint of Entertainment: 6 Mj/$ = Estimated Energy Intensity

For Fossil Energy Footprint of Education: 3 Mj/$ = Estimated Energy Intensity

The energy yield (assumed to be average fossil fuel = liquid fossil fuel) is 73000 Mj/ per 10000 m2 and year. Paper has an energy intensity of 35 Mj/kg. E111 gives the yearly quantity of paper consumed. 0.6 = a factor representing the fact that 60 percent of paper consumed is by the household, and another 40% is released indirectly from the commercial stream due to household activities. (1-F120/100*0.45) calculates to what extent energy is recuperated. F120 gives the percentage of recycling in the household; 0.45 is the percentage of energy that can be saved through recycling. ("Too Good To Throw Away," NRDC)

The energy yield (assumed to be average fossil fuel = liquid fossil fuel) is 73000 Mj/ per 10000 m2 and year. Aluminum has an energy intensity of 250 Mj/kg. E114 gives the yearly quantity of aluminum consumed. (1-F120/100*0.95) calculates to what extent energy is recuperated. F120 gives the percentage of recycling in the household; 0.95 is the percentage of energy that can be saved through recycling. ("Too Good To Throw Away," NRDC)

The energy yield (assumed to be average fossil fuel = liquid fossil fuel) is 73000 Mj/ per 10000 m2 and year. Magnetic metals have an energy intensity of 60 Mj/kg. E115 gives the yearly quantity of magnetic metals. (1-F120/100*0.15) calculates to what extent energy is recuperated. F120 gives the percentage of recycling in the household; 0.15 is the percentage of energy that can be saved through recycling. ("Too Good To Be True," NRDC)

The energy yield (assumed to be average fossil fuel = liquid fossil fuel) is 73000 Mj/ per 10000 m2 and year. Glass has an energy intensity of 15 Mj/kg. E116 gives the yearly quantity of glass consumed. (1-F120/100*0.3) calculates to what extent energy is recuperated. F120 gives the percentage of recycling in the household; 0.3 is the percentage of energy that can be saved through recycling. ("Too Good To Throw Away," NRDC)

The energy yield (assumed to be average fossil fuel = liquid fossil fuel) is 73000 Mj/ per 10000 m2 and year. Plastic has an energy intensity of 50 Mj/kg. E117 gives the yearly quantity of plastic consumed. (1-F120/100*0.7) calculates to what extent energy is recuperated. F120 gives the percentage of recycling in the household; 0.7 is the percentage of energy that can be saved through recycling. ("Too Good to Be Throw Away," NRDC)

Unless otherwise noted, the Arable Land component of the household footprint follows this formula: (World average yield) * (Conversion factor from primary to secondary product, i.e., wheat to bread) * (Quantity in metric or US standard) * (Metric conversion factor, if needed) or (m^2/kg primary product) * (kg primary product/kg secondary product) * (kg secondary product) The conversion factor from primary to secondary product is only included for secondary (manufactured) products. Other terms found in specific formulas are explained in cell notes.

Arable land footprint of eggs: 0.05 refers to 1 egg = 50g =.05 kg

Arable land footprint of liquid vegetable oil and fat: 0.8 = estimated density of vegetable oil (kg/l)

Arable land footprint of food away from home: Value computed by taking the arable footprint of average per capita food consumption without dining out (SUM(H26:H47)) per day (/365), and assuming that each meal eaten out provides one half of the day's nutritional content (*.5). Assumes that every $6 spent is roughly equivalent to one meal. Alternate method: (58/12) = m^2 of arable land per meal. Value computed using estimates of total daily calories consumed per meal eaten out as well as estimated relative vegetable and meat compositions of each meal.

Straw is calculated at the rate the removed biomass can be replaced (to make sure there is no nutrient loss on the field where the straw is grown). As a first approximation, we use cereals biomass productivity as a proxy of bioproductivity potential. On world average land, this productivity is approximately the double of the cereal harvest. Hence, the productivity is 2 * 2641 kg per 10'000 m2 and year.

Be sure to enter your recycling % here

One hectare contains 10'000 square meters or 2.47 acres.

Unless otherwise noted, the Pasture Land component of the household footprint follows this formula: (World average yield) * (Conversion factor from primary to secondary product, i.e., milk to cheese) * (Quantity in metric or US standard) * (Metric conversion factor, if needed) or (m^2/kg primary product) * (kg primary product/kg secondary product) * (kg secondary product) The conversion factor from primary to secondary product is only included for secondary (manufactured) products (bread, cheese, etc.). Other terms found in specific formulas are explained in cell notes.

Grass-fed beef compared to grain-fed beef: The grain-fed beef spends much of its life on grass before it goes into the feedlot. Therefore, we assume that about 65-75% of the pasture for grass-fed beef should still be "charged" against grain-fed beef. The great difference, of course, is the omission of grain, but the comparison still should be larger by the amount of pasture needed for growing the animal until it goes into the feedlot. In reality, the time in the feedlot still requires hay, which is harvested from pasture in many cases, and a case may be made that this is even more energetically expensive because of the haying and hauling operations. For more realistic data, a lifecycle analysis of both pasture-fed and grain-fed cattle is necessary. Note that it is also possible to use the cattle in ecological restoration programs, and then consume them after their use as a "tool" is fulfilled. This effectively would put the livestock into a category that increases "wildlife" resources. While this is rarely practiced today, it is an example of humans living synergistically with other species and compatibly with healthy ecosystems. The trade-off would be between human consumption and consumption by carnivores or other omnivores. Of course, the resources used in meat processing, distribution and preparation for human consumption would remain as an ecological footprint component.

Pasture footprint of dining out: Value computed by taking the pasture footprint of average per capita food consumption without dining out (SUM(I26:I47)) per day (/365), and assuming that each meal eaten out provides one half of the day's nutritional content (*.5). Assumes that every $6 spent is roughly equivalent to one meal. Alternate method: (273/12) = m^2 of pasture per meal. Value computed using estimates of total daily calories consumed per meal eaten out as well as estimated relative vegetable and meat compositions of each meal.

For Pasture Footprint of Higher Course Hydro: (From "Our Ecological Footprint," by M. Wackernagel and W. Rees) 10000/15000000 = square meters of pasture land per MJ 3.6 = MJ/kWh

An average Canadian house uses 23.6 m3 of wood and is assumed to last 40 years (Government of Canada, 1991. The State of Canada's Environment. Ministry of Environment, Ottawa). The house is assumed to contain 150 m2 of living space. 2.6/10000 is the roundwood productivity, 2.2 is the ratio of roundwood needed per unit of construction wood. Another estimate from the Canadian Mortgage and Housing Corporation (OPTIMIZE, 1991) shows the use of over 50 m3 roundwood equivalent for a 350 m2 house.

An average Canadian house uses 23.6 m3 of wood and is assumed to last 40 years (Government of Canada, 1991. The State of Canada's Environment. Ministry of Environment, Ottawa). The house is assumed to contain 150 m2 of living space. 2.6/10000 is the roundwood productivity, 2.2 is the ratio of roundwood needed per unit of construction wood. Another estimate from the Canadian Mortgage and Housing Corporation (OPTIMIZE, 1991) shows the use of over 50 m3 roundwood equivalent for a 350 m2 house.

An average Canadian house uses 23.6 m3 of wood and may last 40 years (Government of Canada, 1991. The State of Canada's Environment. Ministry of Environment, Ottawa). The house may contain 150 m2 of living space. 2.6/10000 is the roundwood productivity, 2.2 is the ratio of roundwood needed per unit of construction wood. Also, the hotel costs are estimated from the average resource use of households. We assume an averege wooden US house would cost 150,000 dollars (with land) and has 2000 square feet. This corresponds to a monthly mortgage cost of 1000 dollars.

The following note explains how the footprint was calculated. The forest component of water is not included in the overall accounting, however, becasue the water footprint can vary according to local situations. In humid areas (like the ones around Xalapa, Mexico), forests can generate in wells and springs about 1'500 m3 of fresh water per hectare and year. Pastures, in contrast, only generate one tenth of this amount. This at a precipitation level of 15'000 m3 per hectare and year (Secretaría de Desarollo Agropecuario y Pescua, SEDAP, Xalapa 1998). In places like British Columbia, this water use may be a secondary function of forest use. In Xalapa, however, at the margin, this water production becomes the primary use of the forest area - therefore, it needs to be added to the footprint.

World average forest yield is 2.6 m3 per 10'000 m2 and year. 600 kg/m3 is the average wood density. 0.53 is the waste factor for fire wood. It means that for each kg of firewood one needs 0.53 kg of roundwood. In this category, the waste factor is significantly smaller than 1 since about twice as much firewood can be produced than roundwood per m2 and year. /2.4: the results are divided by the correction factor for the forest footprint of housing. The reason is that the true footprint of firewood can be calculated quite accurately - while the big error leading to this high correction factor.

World average forest yield is 2.6 m3 per 10'000 m2 and year. 600 kg/m3 is the average wood density. 2.2 is the waste factor

The sub-total for Forest land for Housing does not include the water component because the footprint of water can be very dependent on local situations.

For Forest Component of Paper Products: 10000/2.6 = World average yield of roundwood, in m3/ha 1.65 is the ratio of roundwood needed per unit of paper. 0.6 = a factor representing the fact that 60 percent of paper consumed is by the household, and another 40% is released indirectly from the commercial stream due to household activities.

An average Canadian house uses 23.6 m3 of wood and may last 40 years (Government of Canada, 1991. The State of Canada's Environment. Ministry of Environment, Ottawa). The house may contain 150 m2 of living space. 2.6/10000 is the roundwood productivity, 2.2 is the ratio of roundwood needed per unit of construction wood. Also, the hotel costs are estimated from the average resource use of households. We assume an averege wooden US house would cost 150,000 dollars (with land) and has 2000 square feet. This corresponds to a monthly mortgage cost of 1000 dollars.

For Forest Component of Paper Products: 10000/2.6 = World average yield of roundwood, in m3/ha 1.65 is the ratio of roundwood needed per unit of paper. 0.6 = a factor representing the fact that 60 percent of paper consumed is by the household, and another 40% is released indirectly from the commercial stream due to household activities.

Built-up footprint of lower course hydro: (From "Our Ecological Footprint," by M. Wackernagel and W. Rees) 10000/200000 = square meters of built-up land per Mj 3.6 = Mj/kWh

This area not included since roof area already counted in built area category. (underestimates since embodied energy of PV not yet included)

Assumes that 3000 kWh can be produced from 24 m2 of PV panels (0.75 roughly estimates the embodied energy of PV).

For now, we assign wind energy the same footprint as PV. This formula will change once we are able to calculate the footprint of wind energy.

Calculation for built-up area occupied by roads (allocated to miles travelled): 3.94*10^6 miles = total rural and urban highway miles (public roads and streets) (Bureau of Trans. Stats.) 1609 = meters/mile 25 meters = estimated average width of highways and streets (2.56*10^12) = vehicle miles travelled per year in the US (Bureau of Trans. Stats.) 0.3% of these total miles are bus miles (see Transport sheet).

Calculation for built-up area occupied by roads (allocated to miles travelled): 3.94*10^6 miles = total rural and urban highway miles (public roads and streets) (Bureau of Trans. Stats.) 1609 = meters/mile 25 meters = estimated average width of highways and streets (2.56*10^12) = vehicle miles travelled per year in the US (Bureau of Trans. Stats.) 0.3% of these total miles are bus miles (see Transport sheet).

Calculation for built-up area occupied by transit rail travel (allocated to miles travelled): 6603 miles = total transit rail mileage (Bureau of Trans. Stats.) 1609 = meters/mile 15 meters = estimated track corridor width (2.11*10^10) = total transit rail passenger miles travelled per year in the US (Bureau of Trans. Stats.)

Calculation for built-up area occupied by Amtrak travel (allocated to miles travelled): 25,000 miles = total Amtrak rail mileage (Bureau of Trans. Stats.) 1609 = meters/mile 15 meters = estimated track corridor width (5200*10^6) = total Amtrak passenger miles travelled per year in the US (Bureau of Trans. Stats.)

Calculation for built-up area occupied by roads (allocated to miles travelled): 3.94*10^6 miles = total rural and urban highway miles (public roads and streets) (Bureau of Trans. Stats.) 1609 = meters/mile 25 meters = estimated average width of highways and streets (2.56*10^12) = total vehicle highway miles travelled per year in the US (Bureau of Trans. Stats.) 92.7% of these total miles are cars and light truck miles (see Transport sheet)

Calculation for built-up area occupied by roads (allocated to miles traveled): 3.94*10^6 miles = total rural and urban highway miles (public roads and streets) (Bureau of Trans. Stats.) 1609 = meters/mile 25 meters = estimated average width of highways and streets (2.56*10^12) = total vehicle highway miles travelled per year in the US (Bureau of Trans. Stats.) 92.7% of these total miles are cars and light truck miles (see Transport sheet)

Built-up Land Footprint Component of Goods: 1100 m^2 is the known estimate of the built-up land footprint component of goods (which also includes wastes, sinces wastes are non-durable goods and the byproducts of durable goods). Since not all goods are present in this analysis, we estimate the built up area for each component using the following method: D149 and H149 show the fossil fuel areas for waste and goods respectively. We use these numbers to allocate proportionally the built-up area for goods and waste.

Built-up Land Footprint Component of Services: 1100 m^2 is the known estimate of the built-up land footprint component of services. Since not all services are present in this analysis, we estimate the built up area for each component using the following method: F149 shows the fossil fuel area for services. We use this number to allocate proportionally the built-up area for services.

1.25 = bycatch factor

This column shows the primary biomass equivalence factors. The ratio between them represents their relative capacity to produce biomass. In addition, they are scaled by a factor that keeps the global capacity constant. A factor of 3.2 means that this land category is 3.2 times more productive than world average (bio-productive) land. For details on the equivalence factor calculations, see the "World" sheet of the EF-1996.xls file.

These figures represent the areas of occupied ecologically productive space just added up.

For calculation, see "global EF 1961-97.xls", Sheet CO2 abs, column BD, row 46. This ratio is calculated by the following formula: 73 = 1000 / 20 * 0.9563 / 0.65 where 20 = carbon emission factor of coal, in t carbon/ Tj 0.9563 = carbon absorption of world average forest in [t/ha/yr] including roots and 0.65 = 65% = percentage of CO2 not absorbed by oceans

Waste factor for food: USDA figures reveal that there is on average a ten percent difference between farm weight and retail weight. The 1.10 in the equations above represents this value.

Note: The ecological footprint does not document our entire impact on nature. It only includes those aspects of our waste production and resource consumption that could potentially be sustainable. In other words, it shows those resources that within given limits can be regenerated and those wastes that at sufficiently low levels can be absorbed by the biosphere. For all activities that are systematically in contradiction with sustainability, however, there is no footprint, since nature cannot cope with them. There is no sustainable regenerative rate for substances such as heavy metals, persistent organic and inorganic toxins, radioactive materials, or bio-hazardous waste. For a sustainable world, their use needs to be phased out. In other words, the above footprint calculation assumes that the person being assessed engages in none of these systematically unsustainable activities, be it for example the release of CFCs, the unsafe disposal of motor oil, or the purchase, use and disposal of other harmful household chemicals.