Applied Environmental Consultants,

Transcription

1 Jamie Wilson, Louis C. Thanukos, Ph.D. Applied Environmental Consultants, a JBR Company

2 How did greenhouse gases (GHGs) become regulated? Supreme Court decision in April 2007 ruled that greenhouse gases are air pollutants covered by the Clean Air Act. In April 2009, EPA responded by proposing the endangerment and cause and contribute findings: emissions of greenhouse gases from new motor vehicles cause or contribute to air pollution which may reasonably be anticipated to endanger public health or welfare. Findings finalized in December 2009.

3 EPA passed the light duty motor vehicle emission standards that regulated emissions of six GHG pollutants This meant that GHG were going to become regulated pollutants under the Clean Air Act GHG emissions from stationary sources would then be subject to New Source Review permitting, specifically, Prevention of Significant Deterioration (PSD) The PSD thresholds are much too low for GHGs Therefore, EPA proposed and in May 2010 finalized the GHG Tailoring Rule

4 Goal was to reduce GHG emissions only from the largest sources: New stationary sources that emit 100,000 tons per year (tpy) or more of carbon dioxide equivalents (CO 2 e) based on the global warming potential of each of the six GHG pollutants (CO 2 e is an internationally accepted measure) Modified stationary sources that emit 75,000 tpy or more of CO 2 e New sources or modifications must have mass-based GHG emission increases that follow the traditional PSD thresholds in addition to the increase in CO 2 e

5 The key components of PSD apply to GHGs, including a Best Available Control Technology (BACT) analysis. BACT is typically a top-down approach: 1. Identify available control options 2. Eliminate technically infeasible options 3. Rank options by control effectiveness 4. Evaluate most effective controls and emission limits achievable 5. Select BACT

6 EPA s November 2010 guidance supports the topdown approach for evaluating GHG BACT. All available control options should be evaluated and ranked in descending order of control effectiveness. Select the top option unless technical considerations, energy, environmental, or economic impacts justify that option is not achievable. GHG BACT should be based on CO 2 e, not on individual GHG pollutants EPA s guidance points first and foremost to energy efficiency

7 Step 1 of BACT involves looking at all options for reducing emissions regardless of the source type at which the control was implemented. This may include: Inherently lower-emitting processes and designs Add-on technologies Control methods applied at similar emissions sources Feasible combinations of these technologies The applicant is not required to include options that fundamentally redefine the nature of the source

8 Clean fuels are to be considered unless they redefine the source (e.g., natural gas in lieu of coal for a coal-fired power plant usually redefines the source) EPA will consider granting more innovative control technology waivers [See 40 CFR 52.21(b)(19)] Carbon Capture and Storage (CCS) is considered available by EPA for large CO2- emitting facilities

9 No off-site impacts considered; must represent emissions reduction at facility EPA guidance leaves door open for stricter interpretations by permitting authorities As applicable, use EPA s source category-specific white papers as a starting point: Electric generating units Large ICI boilers Pulp and paper Cement Iron and steel industry Refineries Nitric acid plants

10 In order to elimination an option, need to show the technology is infeasible based on physical, chemical, or engineering principles. Is the technology available? Reached licensing and commercial development stage Compliance with an applicable BACT limit has been demonstrated at similar facility EPA guidance states that lack of vendor guarantees for GHG emissions is not sufficient to eliminate an option CCS generally isn t expected to be reasonable yet for most sources

11 Rank the controls with the best at the top Must rank logical combinations of the technologies Method of measurement historically has been: Control efficiency, Expected emission rate, or Expected emissions reduction For GHGs, EPA guidance suggests an efficiency-based control effectiveness to ensure that the best controls are, in fact, listed first. Consider thermal efficiency by using emissions per unit of output (rather than per unit of fuel input)

12 Beginning with the top-ranked control option, evaluate the economic, energy, and environmental impacts to ensure it is achievable Historically, focus has been on economic considerations, but EPA guidance suggests other impacts are significant for GHG BACT. Economics: direct impacts in $/ton Energy: direct energy consumption Environmental: indirect or collateral impacts

13 From EPA s November 2010 PSD and Title V Permitting Guidance for Greenhouse Gases: There are compelling public health and welfare reasons for BACT to require all GHG reductions that are achievable, considering economic impacts and the other listed statutory factors. Environmental impacts analysis needs to consider interpollutant increases Economic evaluation may be cursory if costs are extraordinary

14 No cost effectiveness threshold ($/ton CO 2 e) provided in the EPA guidance Work Group s Interim Phase I Report identifies cost effectiveness range from $3-$150/ton CO 2 e Additional economic factors (new for GHGs): High control cost relative to project cost Potential movement to overseas production Local job losses Permitting authority (and applicant!) must provide adequate justification for eliminating control options

15 Select BACT based on the most effective control option (or combination of options) that was not eliminated in Step 4 Form of permitted BACT standards varies but should consider or may include: Emission limits Averaging time periods Equipment specifications Work practices Associated monitoring, recordkeeping, and reporting EPA advocates BACT limits with longer averaging periods to address GHG emissions

16 BACT for GHGs may include work practices such as an Environmental Management System (EMS) focused on energy efficiency ENERGY STAR program provides guidance BACT limit may include implementation of energy saving measures identified by the EMS Work practices are only acceptable in lieu of a numerical emission limit if it is technically impractical to establish or ensure compliance with a numerical limit.

17 EPA s sample GHG BACT assessments Municipal solid waste landfill Natural gas-fired boiler Hydrogen plant at petroleum refinery Coal-fired electricity generating facility Kiln at a cement plant Natural gas compressor station Gas-fired combined cycle power plant

18 PSD BACT determinations for criteria pollutants have a long and sordid history GHG BACT can benefit from that experience but opens up a new realm of opportunity for judgment calls by the regulatory agencies Review EPA s white papers and sample BACT analyses that may be relevant to your industry or equipment. Always keep energy efficiency in mind when designing a new facility or a modification to an existing facility!

19 Jamie Wilson (480)