The Baseline Energy Calculator yields the estimated energy use and CO2 emissions associated with losses through the building envelope, appliances and devices within residential and commercial buildings in the United States. The energy use and CO2 emissions can be divided by building type, climate zone, technology, and other factors indicated below. CO2 emissions reported here do not include direct emissions associated with losses of working fluids from heating, cooling, water heating, and refrigeration systems.

To obtain an estimate for an energy use segment of interest, the applicable category selections must be made below. In each category shown, at least one selection is required. In some categories, multiple selections are permitted. Follow the numbered steps below, making the desired selections at each step. Once selections have been made in each category, click the 'Calculate' button at the bottom right of the screen to obtain the energy use and associated CO2 emissions results. Initial results may cleared by clicking the 'Reset' button or updated by clicking the 'Calculate' button again.

The underlying data for this calculator are from the 2019 Annual Energy Outlook (AEO) released by the U.S. Energy Information Administration (EIA).

Segment Size
(Primary Energy)
(CO2 Emissions)
1. Select a projection year
2. Select relevant climate zone(s)
(Or select from the map)
  • AIA CZ1 <2,000 CDD and >7,000 HDD

  • AIA CZ2 <2,000 CDD and 5,500-7,000 HDD

  • AIA CZ3 <2,000 CDD and 4,000-5,499 HDD

  • AIA CZ4 <2,000 CDD and <4,000 HDD

  • AIA CZ5 >=2,000 CDD and <4,000 HDD

3. Select building type(s)
4. Select end use(s) and technology type(s)
* ‘Other’ end use calculations do not reflect ‘Other (Unspecified)’ non-building energy loads in the commercial sector. These additional loads are reflected in the ‘Other Uses’ end use category of the Annual Energy Outlook reference case tables for the residential and commercial sectors (see ‘Total Energy Consumption by End Use’ rows). The use of Scout (including this website) is subject to the license terms .