Reducing NOx Emissions Using Energy Efficiency and Renewable Energy
Accurate quantification of emission reductions from energy efficiency and renewable energy (EE/RE) measures is challenging due to the complex nature of the electrical grid system. At any given time, it is impossible to determine exactly where on the electrical grid electricity comes from for any certain electrical user.
The U.S. Environmental Protection Agency's (EPA's) 2004 guidance for claiming emission reductions from EE/RE presents additional challenges for taking direct credit for EE/RE measures, particularly in areas that have a NOx cap and trade program. The EPA guidance also requires additional commitments from states claiming reductions from EE/RE measures.
In the past, the TCEQ specifically included NOx emission reductions from EE/RE measures in the state implementation plan (SIP). In more recent SIP revisions, the TCEQ has not taken direct credit for EE/RE measures due to the challenges associated with quantification and EPA guidance.
EE/RE and the State Implementation Plan
In the December 2002 HGB SIP revision, a methodology was developed with the support of the EPA and the Texas A&M Energy Systems Laboratory to estimate NOX reductions resulting from EE/RE measures.
The EPA’s Emissions and Generation Resource Integrated Database was used to spatially allocate the energy reductions in each of the eight HGB counties to electric generating units located in those counties or outside the HGB area. However, this methodology does not address the complication created from the NOXMass Emissions Cap and Trade Program in the HGB area.
San Antonio Area
The November 2004 San Antonio Early Action Compact included 0.06 ton per day of NOX emission reductions in 2007 from energy-efficiency projects as a result of Senate Bill 5 (2001) and Senate Bill 7 (1999).
Dallas–Fort Worth Area
The April 2005 DFW 5 Percent Increment of Progress SIP revision in included NOX emission reductions of 0.72 ton per day in 2007 from EE/RE projects in the DFW 1997 eight-hour ozone nonattainment area.
The reductions were calculated based on electricity and natural gas usage reductions from implementation of the May 1, 2001, Texas Building Energy Performance Standards to single and multi-family residences in 2003.
These reductions also include less energy use because of energy efficiency measures implemented by local governments and utilities as reported to the Public Utility Commission of Texas and State Energy Conservation Office.
- EPA's Roadmap for Incorporating EE/RE Policies and Programs into SIPs, March 2011 (Document EPA-456/D-11-001)
- EPA Guidance on SIP Credits for Emission Reductions from Electric-Sector EE/RE Measures, August 5, 2004
- TCEQ Presentation on EE/RE in Early Action Compacts as part of Senate Bill 5 Workshop San Antonio, March 30, 2004
- Incorporating EE/RE Projects into the SIP—A Guide for Local Entities, February 6, 2004
- Texas A&M Energy Systems Lab Calculator, IC3 energy code compliance software based on the Texas Building Energy Performance Standards
- State Energy Conservation Office Compliance with Senate Bill 5 and Senate Bill 12 Energy Efficiency Programs
- Texas Energy Partnership resources to facilitate compliance with Senate Bill 5, 77th Legislative Session, and Senate Bill 12, 80th Legislature Session, for energy efficiency and renewable energy in Texas
- Senate Bill 5, 77th Legislative Session
- Senate Bill 12, 80th Legislative Session
- The Energy Systems Laboratory is a division of the Texas Engineering Experiment Station and a member of the Texas A&M University System
- Contact Bob Gifford, Air Quality Planning Section, at 512-239-3149 for additional information.
- Sign up to receive e-mail updates on SIP-related information, including information on EE/RE. Select SIP Hot Topics under the Air Quality heading.