NEMS Historical Data Availability For ftab Tables 1 – 18, Years = 1995 - 2005

Summary

Skelly (12/4/06): In AEO2007, 2005 will represent the last history year for most data.  We try to make sure that data in the last two history years (2004-2005) match data sources, as these years are published in the AEO. The footnotes in the AEO appendix tables provide data sources, but as the footnotes indicate, sometimes the data is based on model simulations that are not perfectly calibrated to reproduce the actual EIA data sources.   The same is true, unfortunately, for the 1995-2003 span, and since we don't publish those data years, we don't always worry too much about making them match.  See table by table specifics below.

Table #1 Total Energy Supply and Disposition Summary (quadrillion Btu, unless otherwise noted)

Skelly (12/4/06): Consumption data on Table 1 matches the totals in Table 2. 

Table #2 Energy Consumption by Sector and Source (quadrillion Btu, unless otherwise noted)

Skelly (12/4/06): Most of Table 2 matches history, but the Electric Power sector consumption data is simulated in the most recent history years.  Some of the oil product detail (especially distillate and residual) is problematic and does not necessarily match EIA sources at the sectoral level.  But I think for your purposes, you can assume that fuel consumption data by sector matches history for residential, commercial, industrial, and transportation.  The fuel totals in Table 2 will be off slightly from say, the Annual Energy Review, mainly because of the situation with electric power. Ideally, for fuel consumpiton in the electric power sector, what should be evaluated is how well the model forecasts generation by fuel type, rather than fuel consumption.  The model uses fixed (fixed over time) relationships termed heatrates to estimate fuel consumption from generation-by-fuel. So the model's simulation over the history years is not going to match actual fuel use, even though its generation data matches history, because average heatrates vary over time.

Table #3 Energy Prices by Sector and Source (2005 dollars per million Btu, unless otherwise noted)

Skelly (12/4/06): Table 3--Doesn't necessarily match history 1995-2003.  The 2004-2005 prices should be fairly close.  Often, EIA doesn't publish enery prices in $/mmbtu units, so comparing the values to the actual data sources isn't that easy.  It requires conversion factors.

Table #4 Residential Sector Key Indicators and Consumption (quadrillion Btu, unless otherwise noted)

Skelly (12/4/06): Table 4 Residential fuel by end use:  1997 and 2001 linked to RECS survey data. 1995-1996 are zero.

Table #5 Commercial Sector Key Indicators and Consumption (quadrillion Btu, unless otherwise noted)

Boedecker (12/4/06): At issue is the validity of using AEO 2006 projections to represent "actual" 2005 floorspace.  Commercial floorspace is the logical choice as the driver for commercial energy because demand for the major end-use services (heating, lighting, cooling, ventilation, etc.) is typically dependent on the amount of space to be heated, lit, cooled, etc.  Unfortunately, there is no publicly available historical time series providing annual estimates of U.S. commercial floorspace.

The NEMS representation of the commercial sector is based on the latest available EIA Commercial Buildings Energy Consumption Survey (CBECS), while floorspace growth is projected via equations in the macroeconomic module.  The macroeconomic equations were developed using the proprietary F.W. Dodge commercial floorspace database.  The latest Dodge update was received in late 2004, guaranteeing that the 2005 values are projections rather than "actual" values.  

Given the proprietary nature of the Dodge data, CBECS estimates are the only publicly available "actual" values for U.S. commercial floorspace.   Given the periodic nature of the CBECS, comparison of projected and "actual" commercial sector variables should be limited to CBECS survey years with "historical" floorspace estimates taken directly from CBECS rather than from AEO projections.

Even using CBECS estimates presents complications, due to discontinuities between surveys.  Changes in survey coverage and sample variability prevent a smooth transition when updating the NEMS commercial floorspace from one CBECS survey to the next.  This is clearly illustrated in the "dynamic profile" for commercial energy intensity (energy use per square foot) mentioned in your example (see below).

2005 Commercial Sector Energy Intensity (Thousand Btu per Sq. Ft.)

AEO Year	1998	1999	2000	2006
Measure	103.8	125.6	123.4	110.7

I also have a slight qualification for the commercial table.

Table 5 Commercial fuel by end use - 2004 values represent projections one year after the latest CBECS.  That is, the latest CBECS provides estimates for 2003, the first year the commercial module runs is 2004.

The 2004 values would be the closest to CBECS available from the restart file.

Table #6 Industrial Sector Key Indicators and Consumption

Honeycutt (12/6/06): It is true that the history values in the aeo2007 restart file reflect our current view of history for value of shipments.  However, almost every year we have a different notion of what the history values really are.  Further, the concept occasionally changes from gross output in 1987 dollars to 1992 dollars or to values of shipments in 1996 or 2000 dollars.  The different concepts cannot be simply imposed on previous versions of the model that used different concepts.

There is a similar problem with the industrial energy data.  While the aeo2007 restart file has what we currently believe to be "correct" history values, previous aeo restart files also had data thought to be correct.  You will notice very large changes in the aeo99 to aeo2001 period just because EIA's "history" changed (e.g., the "history" value for industrial biomass changed by 50 percent).  

Table #7 Transportation Sector Key Indicators and Delivered Energy Consumption

Skelly (12/4/06): Table 7 Energy consumption pretty well matches history.  Fuel use by mode is estimated and may not match any actual data source.  Various times series, like VMT and MPG, and stock numbers, match the history as we know it.

Maples (12/5/06): I'd like to add a couple qualifications for the transportation data:

1) Non-EIA published historical transportation energy data (USDOT fuel sales data collected for tax collection purposes) doesn't match EIA reported energy data by mode/fuel type, which creates problems for us modelers particularly when benchmarking to EIA published values.  As EIA/DOT addresses these discrepancies, I assume EIA reported historical energy use data by sector will be updated.

2) Historic vehicle travel and on-road fuel economy data published in the AEO are taken from the FHWA Highway Statistics.  As FHWA gains access to new survey data, they often revise previously published historic data to reflect the newly derived information.  For example, for 2004 FHWA revised both travel and on-road fuel economy estimates for light duty trucks and single axle commercial trucks, which lowered the fuel economy and increased the travel for light duty trucks while doing the opposite for the single axle commercial trucks.  FHWA has indicated that they will be updating some portion of the time series data for light duty trucks, single axle commercial trucks, and heavy trucks to reflect the updates made in the 2004 reported data.

3) Not all historical data included in the ran file are updated annually.  Many data items in the transportation tables are derived from purchased databases (that we can not afford to buy annually) and/or periodic surveys (e.g. VIUS).  Vehicle stocks currently reflect actual historic data through 2001 for light duty vehicles, 2000 for heavy duty trucks, 2003 for fleet vehicles, and 2005 for aircraft, the remaining historic years are model estimates.  The light, heavy, and fleet vehicle stocks will be updated for the next AEO, which will change the historic values.

Table #8 Electricity Supply, Disposition, Prices, and Emissions (billion kilowatthours, unless otherwise noted)

Skelly (12/4/06): Table 8 Electricity Generation by fuel in the electric power sector, and electricity sales should match history 1995-2005.  Don't know about electricity prices.  Prices by component are probably estimated.

Table #9 Electricity Generating Capacity (gigawatts)

Probably not to be considered in the first round of NEMS forecast evaluations.

Table #10 Electricity Trade (billion kilowatthours, unless otherwise noted)

Probably not to be considered in the first round of NEMS forecast evaluations.

Table #11 Liquid Fuels Supply and Disposition (million barrels per day, unless otherwise noted)

No response.

Table #12 Petroleum Product Prices (2005 cents per gallon, unless otherwise noted)

No response.

Table #13 Natural Gas Supply, Disposition, and Prices (trillion cubic feet, unless otherwise noted)

Skelly (12/4/06): The values reported for 1995-2005 match history. See discussion below for Table #14

Table #14 Oil and Gas Supply

Benneche (12/5/06): The oil and gas data match history to the extent that we know it from 1990 to 2005.  This does not necessarily mean that it matches EIA historical data in all cases.  However, it does represent the data that were used in developing the forecast, so it should be consistent with the forecast values in a given AEO.  Unfortunately in some cases we have changed "history" and not just for definitional reasons, but because of newer and hopefully better data.  Definitional changes are always a potential problem.  For example, I changed the definition of the natural gas price to the transportation sector in AEO2007.  We had some problems last year with the definition of natural gas production in Texas because of the incorrect inclusion of CO2 in the original data.  Most every year the unconventional gas production history gets revised, which in turn causes a change in the conventional onshore category.  The gas price to electric generators has been a problem because of coverage and has undergone revision.  The gas price to industrials is always a problem because it is estimated.  Finally, the national average prices will also depend on the regional quantity weights, which can throw them off as well.

Table #15 Coal Supply, Disposition, and Prices (million short tons, unless otherwise noted)

Skelly (12/4/06): The values reported for 1995-2005 match history for production and consumption. Not sure about prices.

Mellish (12/12/06): the coal model, we overwrite all of the historical data from 1998 onward (through 2005 in the AEO2007).  So, theoretically, all of the data items for the historical time period (excepting 1995 through 1997) in ftab Table 15 should match history.  The attached file shows that we may have entered an incorrect number for other industrial coal consumption for 2002 (see worksheet labeled 'ftab vs data').

There are some definitional issues that mean that our historical data differs from numbers published in EIA data publications.  One such exception is that we publish an average minemouth price number that includes both captive and open market coal mines, whereas, beginning in 2001, EIA data publications shifted to publishing an average minemouth price number that excludes production from captive coal mines.  

Table #16 Renewable Energy Generating Capacity and Generation (gigawatts, unless otherwise noted)

Skelly (12/4/06): The values reported for 1995-2005 match history.

Table #17 Carbon Dioxide Emissions by Sector and Source (million metric tons carbon dioxide equivalent, unless otherwise noted)

Skelly (12/4/06): The values reported for 1995-2005 match history.

Table #18 Macroeconomic Indicators (billion 2000 chain-weighted dollars, unless otherwise noted)

Skelly (12/4/06): The values reported for 1995-2005 match history.

Unruh (12/19/06): The issues Crawford raised concerning the industrial activity driver similarly pertain to GDP in Table 18:  change in year's $ ('87 to '92 to '97 to 2000), fixed- v. chain-weighting of detailed components, redefinition of concept (GNP to GDP, inclusion of software in consumption, etc.), etc.  Therefore, even though the history is correct according to our latest understanding and estimate of the GDP concept, it may not be comparable to what was projected in early AEOs.