Release date: February 2006



Appendix B. Data and Forecast Characteristics

The information shown in this report is derived entirely from the National Energy Modeling System (NEMS). This is done to provide a consistent basis for the year-to-year changes in renewable energy equipment due to the EPACT Section 206 rebate program. The Annual Energy Outlook 2006 Reference Case projections do not include the impact of EPACT Section 206 because the Energy Information Administration (EIA) only includes the effects of those laws for which Congress has appropriated funding. As of December 31, 2005, Congress had not appropriated funding for Section 206 programs.

Although Section 206 covers both residences and small businesses, no EIA data exist on small businesses, which would largely impact the commercial sector. Accordingly, only the residential sector is examined in this report.

The data shown in this report for 2004 and 2005 are derived from the NEMS Residential Demand Module. This module uses information from EIA's 2001 Residential Energy consumption Survey (RECS) as its base-year data. It then generates forecasts for each year through 2025 using actual and forecasted weather as well as exogenous forecasts of housing units, energy equipment and appliances, and energy use. These procedures are performed for each of the nine Census Divisions.

EIA's published estimates of residential wood energy consumption are derived somewhat similarly but do not account for changes in housing stocks. Also, estimates are developed only at the national level. For geothermal heat pumps (GHPs), EIA does not publish a stock estimate but does estimate the energy that they offset. This energy estimate is based upon estimates of GHPs, technical performance data, and usage from the Oregon Institute of Technology's Geo-Heat Center. EIA has annual estimates of solar thermal and photovoltaic equipment dating back to the early 1980s and can makes a good estimate of the stock of each with assumptions about retirements. Energy use is calculated in a similar manner to that done by the Residential Demand Module, making assumptions about product efficiencies.

The NEMS Residential Demand Module only forecasts technologies which are included in the RECS, which is fielded every 4 years. Since RECS does not collect information on residential wind turbines or any other form of biomass except wood,^[9] NEMS does not forecast these technologies.

Further information on the Residential Demand Module may be found in the EIA's Assumptions to the Annual Energy Outlook 2005, pp. 19-26 (http://www.eia.doe.gov/oiaf/aeo/assumption/pdf/0554(2004).pdf).