Calculator Details

Overview

The Root360 calculators are designed to estimate annual costs and environmental impacts from your business’s building energy, water, and transportation use. These are not exact calculations but rather approximations based on data you enter; for the most accurate estimates, the data entered should be representative of your business’s typical energy and water use. Root360 then suggests several behavior and equipment changes, and allows you to explore the financial and environmental savings from adopting those changes. You are encouraged to choose a timeframe in which to adopt each of these changes. Then, based on your selections, Root360 will email you a reminder of your commitments and ask which changes you have implemented.

Determining Annual Consumption

All three calculators require annual figures. If you have only monthly figures, you can either (1) take a typical monthly bill and multiply that usage volume and cost by 12, or (2) for more exact annual figures, add the amounts from 12 consecutive monthly bills.

Energy calculator

Natural gas unit conversions:
Natural gas volume is typically billed monthly in hundreds of cubic feet (Ccf or Hcf), thousands of cubic feet (Mcf), or in therms. The Root360 calculator requires the volume to be entered as annual cubic feet (cf).

How to convert monthly volume to annual cf:

Ccf/Hcf to cf:
Multiply monthly Ccf/Hcf volume by 100 to get monthly cf, then multiply by 12 to get annual cf.
(Example: 95 Ccf/Hcf x 100 x 12 = 114,000 cf/yr.)

Mcf to cf:
Multiply monthly Mcf volume by 1,000 to calculate monthly cf, then multiply by 12 to get annual cf.
(Example: 8.4 Mcf x 1000 x 12 = 100,800 cf/yr.)

Therms to cf:
Multiply monthly Therms volume by 99.9761 to get monthly cf, then multiply by 12 to get annual cf.
(Example: 36 Therms x 99.9761 x 12 = 43,190 cf/yr.)

Water calculator

Water unit conversions:
Water use is typically billed quarterly (every 3 months) with the volume measured in either hundreds of cubic feet (Ccf or Hcf) or gallons (gal). The Root360 water calculator requires the volume to be entered as annual gallons.

How to convert quarterly volume to annual gallons:

Ccf/Hcf to gallons:
Multiply quarterly Ccf/Hcf volume by 748 to get quarterly gallons, then multiply by 4 to get annual gallons.
(Example: 20 Ccf/Hcf x 748 x 4 = 59,840 gal/yr)

Transportation calculator

If you do not know the fuel efficiency of your vehicle(s), go to http://www.fueleconomy.gov/ to find the U.S. Environmental Protection Agency’s estimated city and highway mpg (miles per gallon) for your specific make(s) and model(s).

Calculator Assumptions

The equations used in each calculator are based primarily on data from the U.S. Environmental Protection Agency (EPA) and U.S. Department of Energy (DOE), with limited data also gleaned from relevant corporate and association websites. We will update the data used in the equations periodically, or as needed to reflect significant changes.

Building Energy

If you do not have your energy costs on hand, you can estimate your costs using average regional or national fuel prices.[1]

To estimate carbon dioxide (CO2) emissions from energy use, we used the following constants from the EPA and DOE:

Electricity: 1.232 lbs/kWh[2]

Natural gas: 0.1199 lbs/cubic ft[3]

Propane: 12.7 lbs/gal[4]

Heating oil: 22.4 lbs/gal[5]

To estimate cost and emission savings resulting from best management practices (BMPs), we assumed:

BMP #1: Lowering your heating thermostat by one degree for a 24-hr period uses 3% less fuel.[6]

BMP #2: Increasing your cooling thermostat by one degree for a 24-hr period uses 3% less fuel.[7]

BMP #3: Lighting, electronics, and computers consume 19% of a typical commercial business’s electricity use.[8] Turning off these items at the end of the day shuts them down for 15 hrs/day (assumes 9-hr work day); therefore, new consumption is 37.5% of former consumption.

BMP #4: Lighting consumes 14% of a typical business’s electricity use.[9] ENERGY STAR® lighting uses 75% less electricity than incandescent lighting.[10]

BMP #5: Cooling consumes 10% of commercial energy use.[11] ENERGY STAR® air conditioning units use 15% less energy than conventional units.[12]

Water

To estimate cost savings and water use reductions resulting from best management practices (BMPs), we assumed:

BMP #1: Toilets consume 12.2% of a typical office building’s water use.[13] Replacing 3.5 gpf (gallon per flush) toilets with 1.28 gpf models reduces water use by 63%.[14]

BMP #2: Bathroom faucets consume 0.69% of a typical office building’s water use.[15] Replacing 2.2 gpm (gallons per minute) faucets with 1.5 gpm models reduces water use by roughly 32%.[16]

BMP #3: Using foam soap instead of liquid soap leads to a 16% water savings per wash.[17]

BMP #4: Dishwashers account for 42% of kitchen water use and 1.9% of a facility’s total water use.[18] Replacing an 8 gallon dishwasher with a 4.25 gallon model reduces water use by roughly 47%.[19]

BMP #5: Use of WaterSense-labeled irrigation products results in a 15% water use reduction.[20]

Transportation

To estimate costs from current energy use, we used national average gas and diesel prices from DOE’s Energy Information Administration.[21] To calculate GHG emissions from gasoline and diesel vehicles, we used the constants 19.62 lbs/gal and 22.38 lbs/gal, respectively.

Flight carbon dioxide emissions assumptions:

Category Emissions
(lbs/person/mi)
Short 0.559974
Medium 0.449743
Long 0.399037
International 0.379195

 

Flight distances & examples:

Category Distance, round trip (mi) Distance used in calculations, round trip (mi) Flight example Flight time, one way, non-stop
Short <400 399 RDU (Raleigh, NC) to DCA (Washington, DC) 1.5 hr
Medium 400-1,500 1,500 STL (St. Louis, MO) to SAT (San Antonio, TX) 2.5 hr
Long 1,501-3,000 3,000 MDW (Chicago) to LAX (Los Angeles) 4.5 hr
International >3,000 10,000 JFK (New York) to GRU (Sao Paolo, Brazil) 10 hr

 

Best management practice (BMP) assumptions:

BMP #1: To calculate savings from a mile per gallon (MPG) increase in fleet fuel efficiency, we used the following before[22] and after MPG figures for each of the five vehicle categories:

Current MPG 1 MPG improvement
40+ 46
30-39 36
20-29 26
10-19 16
5-9 9

BMP #2: Adopting EPA SmartWay technologies for your tractor trailers will reduce fuel consumption by an average 15%.[23]

BMP #3: Adopting more conservative driving habits (e.g., gradual acceleration and braking, observing the speed limit) can improve your fuel efficiency by 33%.[24]

BMP #4 and #5: Reducing current vehicle and air travel can result in a significant cost savings and reduction in CO2 emissions.

Sources

[1] Sources: http://www.eia.gov/dnav/pet/pet_pri_wfr_dcus_nus_m.htm (Mar 2015), http://www.eia.gov/dnav/ng/ng_pri_sum_dcu_nus_m.htm (Jan 2015), and http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_5_6_a (Jan 2015).
[2] Source: http://www.epa.gov/cleanenergy/documents/egridzips/eGRID_9th_edition_V1-0_year_2010_GHG_ Rates.pdf.
[3] Source: http://www.eia.gov/environment/emissions/co2_vol_mass.cfm.
[4] Source: http://www.eia.gov/environment/emissions/co2_vol_mass.cfm.
[5] Source: http://www.eia.gov/environment/emissions/co2_vol_mass.cfm.
[6] Source: http://energy.gov/energysaver/articles/thermostats.
[7] Source: http://energy.gov/energysaver/articles/thermostats.
[8] Source: http://buildingsdatabook.eren.doe.gov/TableView.aspx?table=3.1.4.
[9] Source: http://buildingsdatabook.eren.doe.gov/TableView.aspx?table=3.1.4.
[10] Source: Putting Energy Into Profits: ENERGY STAR® Guide for Small Businesses, http://www.energystar.gov/ia/business/small_business/sb_guidebook/smallbizguide.pdf.
[11] Source: http://buildingsdatabook.eren.doe.gov/TableView.aspx?table=3.1.4.
[12] Sources: http://www.energystar.gov/products/certified-products/detail/air-conditioning-room and http://www.energystar.gov/products/certified-products/detail/air-conditioning-central.
[13] Source: http://www.pacinst.org/wp-content/uploads/sites/21/2013/02/appendix_e3.pdf.
[14] Source: http://www.epa.gov/WaterSense/products/toilets.html.
[15] Source: http://www.pacinst.org/wp-content/uploads/sites/21/2013/02/appendix_e3.pdf.
[16] Source: http://www.epa.gov/WaterSense/products/bathroom_sink_faucets.html.
[17] Source: http://www.environmentalleader.com/2014/06/26/water-consumption-reduced-with-one-simple-change/.
[18] Source: http://www.pacinst.org/wp-content/uploads/sites/21/2013/02/appendix_e3.pdf.
[19] Source: https://www.energystar.gov/products/certified-products/detail/dishwashers.
[20] Source: http://www.epa.gov/watersense/docs/ws_irrigationcontrollers_commerciallandscape_508.pdf.
[21] Source: http://www.eia.gov/petroleum/gasdiesel/ (4/13/15).
[22] Source: July 2014, http://www.eia.gov/todayinenergy/detail.cfm?id=17211.
[23] Source: http://www.epa.gov/smartway/about/documents/basics/420f14006.pdf.
[24] Source: http://www.fueleconomy.gov/feg/pdfs/OwnerRelatedFuelEconomyImprovements.pdf.

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