How does the EPA Arrive at the 2030 Goal?

EPA determined State emissions rate and mass goals for 2030 according to the following approach. See the listed resources for additional information.

  1. Determine baseline CO2 emissions and electricity generation:

    1. Obtain 2012 net emissions and net electricity generation for each of the “likely affected electricity generating units (EGUs)” (see excluded EGUs) by category (Coal; O/S; NGCC)

    2. Sum these by State (total net emission/ total net generation) within category

    3. Adjust for EGUs under construction, hydro anomaly, or major anomalous outages

    4. Sum to Region in each category = Adjusted Regional emissions rate : 2012 base-case; by category. Note: Coal and O/S are combined into “fossil steam” at this step…for simplicity we continue to call it “Coal”.

  2. Apply Building Block 1 (HRI: heat rate improvements goals- a percent reduction in the amount of fuel required for each MWh produced, region specific) to baseline Regional Coal emissions rate = reduction in total CO2 emissions per MWh.

  3. Apply Building Block 3 (expected incremental Renewable Energy – year and region specific, assume zero net emissions per MWh) to e-generation; proportional to the State’s portfolio of electric production: e.g. if your state has 2.5% of affected generation, your state is assigned 2.5% of projected new RE MWh. Those new State RE MWh are apportioned to replace Coal and NGCC at their respective production ratio: e.g. if 70 % of MWh is generated by coal, than 70% of new RE that year goes toward reducing Coal emissions: = replacement of some ‘dirtier’ e-generation with clean generation and thus a reduction in emissions per total MWh

  4. Then apply Building Block 2 (NGCC capacity factor increase: i.e. how much of the time is each plant actually operating in a given year– goal is up to 75% of historical achieved summertime adjusted capacity by 2030) = increase in e-generation at a modest emissions rate –increases in NGCC generation further offsets the need for coal burning generation

  5. combine step B/C/D to obtain new Regional emissions and generation by category = new post-Building Block emissions rate for fossil steam (coal + O/S) units and NGCC units.

  6. Within each category and region, determine the least stringent (dirtiest) emissions rate for each year; use this rate as the category specific interim and final 2030 goal emissions rate = these interim and final rates are applied equally to all States.

  7. Apply 2030 goal emissions rate (by category) to each State’s baseline generation from likely affected EGUs; assuming same level of total generation = State Emissions Goal expressed as a rate which can be converted to total mass relative to base case generation level.

  8. State may use any combination of on-site or off-site approaches for meeting the interim and final State Goal (i.e. the State is NOT required to achieve the assumptions used for calculating the goal, they ARE required to present a plan demonstrating how other pathways will be used to reach the same goal.)

Notes

  • The EPA approach relies primarily on expanding the electricity production and reducing emissions from existing “likely affected units.” Various affected EGUs are scheduled for retirement prior to the compliance timeline, and some completed projects will reach the commercial market during the interim compliance period.

  • Significant technological updates and new construction projects must meet certain emissions standards according to the EPA’s performance standards for modification or reconstruction projects (80 FR 205/2 64510 Oct 2015), and new source performance standards (79 FR 1430 1466/3 Jan 2014).

  • Expected new Renewable Energy production estimates are based on an acceleration of recent historical trends in commercial RE additions and assumed to replace demand from polluting EGUs.

  • Carbon capture and storage technologies are a potential method for reducing emissions without changing generation, but are not significantly commercially available and are not included in myCPP.

  • The State goal calculations do not account for changes in consumer demand resulting from energy efficiencies, private generation, or the number of consumers – each may influence the development of a State Plan.

Example calculations for Alabama

Using baseline data from EPA’s “tsd-cpp-emission-performance-rate-goal-computation-appendix-1-5.xls"

Alabama has 39 Coal and O/S steam EGUs included - generating 46,059,840 MWh in 2012, resulting in a Calculated emissions rate of 2,263 lb CO2/MWh (this represents 46% of the share of likely affected EGU electricity production). Additionally, there are 55 NGCC EGUs generating 53,492,096 MWh yielding an annual capacity factor of 65% of the achieved summertime capacity or 59% of annual nameplate capacity (10333 MW). NGCC in AL has a calculated emissions rate of 877 lb CO2/MWh. This yields a combined baseline emissions rate of 1518 lb CO2/MWh for the state (shown as a red line in the bar graph). There are 221 total excluded EGUs – encompassing substantial hydropower, nuclear, and geothermal electricity. Significant biomass combustion also occurs within the non-commercial sector, and thus is not considered in the CPP. Most wind power is purchased as RE credits from out-of-state units.

Alabama’s 2030 State goal is 1,018 lb CO2/MWh (equivalent to 56.8 million tons CO2 from 2030 generation). EPA calculates this goal from a regional HRI goal of 4.3%; estimated new RE of 28,240,000 MWh (4% of the projected national new RE in 2030, applied incrementally) which offsets demand; and NGCC capacity increase to 61,123,464 MWh (i.e. 67.3% of nameplate capacity which is equivalent to 75% of AL historical summer capacity.) EGUs scheduled for retirement in AL between 2013-2019 are not accounted in the goal, but includes 644,736 MWh of coal and 155,852 MWh of hydropower.

Using the tool functionality you can visualize several options for reaching the State goal.

Results of myCPP are APPROXIMATE based on EPA methodology and a variety of data sources. Expected EGU retirements and new construction should also be considered for determining each State Plan; data on these are not included in the tool. When considering planned construction remember that “nameplate capacity” is an absolute maximum annual generation under 100% operating hours at 100% operating efficiency – typical actual net generation is rarely more than 75% of this value and often below 50%, depending on the category of electricity generation technology. Each State is expected to work with EPA project coordinators to verify and finalize State Plan components by June 30, 2016 or if an extension had been applied for and granted, by June 30, 2017.

See the myCPP User Guide

Primary resources:

tsd-cpp-emission-performance-rate-goal-computation.pdf and tsd-cpp-ghg-mitigation-measures.pdf found at:

http://www.epa.gov/cleanpowerplan/clean-power-plan-final-rule-technical-documents