Calculating Emissions Reductions: Module 2B

Transcription

1 Calculating Emissions Reductions: Module 2B Presented by Chris James and John Shenot September 6, 2012 The Regulatory Assistance Project 50 State Street, Suite 3 Montpelier, VT Phone: web:

2 Overview of Module 2B: Calculating Emissions Reductions 1. Data needed 2. Location and time of day considerations 3. Understanding how emissions factors are calculated and used 4. Methods to determine emissions saved: Average emissions Marginal emissions Stochastic process Dispatch modeling

3 1. Which Type of Energy Savings to Use? (Refresh from Module 2A) Savings can be determined by measure, program, project and portfolio How much time and effort can you devote? Can another agency help you? Is it important for you to do most or all of the analysis yourself?

4 1. Data Needed Quantity of energy saved (from data sources like those we discussed in module 1) What are you going to include in your analysis? Individual measures, project(s), program(s) or portfolio? Installation rate, persistence and lifetime of measures, program, project or portfolio analyzed N.B., the more granular your analysis, the more time and effort it will take. Precision will improve, but compared to the protocols used for some traditional control measures, that may be less important Decide whether coincidence between times that energy is saved and when pollutant levels are high matters to you

5 2. Location and Time of Day Considerations 5

6 Methods to Determine Emissions Saved Average emissions method Marginal emissions method Stochastic process Dispatch modeling

7 3. Calculation and Use of Emissions Factors Types: Average (across all units, for an entire state, default to a regulatory limit) Marginal (emissions for the last unit to be dispatched in a given hour) Unit level from stochastic and dispatch modeling

8 4. Methods to Determine Emissions Saved- Average Emissions Method Simple, may be less precise than other methods, but acceptable for first-order approximation Examples: Regulatory limit for NOx: 1.5 lbs/mwh Average emissions for the power pool or state

9 Methods to Determine Emissions Saved- Average Emissions Method (cont.): Central Region of US

10 SPNO SPP North SPSO SPP South SRMV SERC Mississippi Valley Methods to Determine Emissions Saved- Average SRMW SERC Midwest SRSO SERC South Emissions SRTV SERC Tennessee Valley Method (cont.): NERC Sub-Regions SRVC SERC Virginia/Carolina U.S Used for Egrid Emissions Factors This is a representational map; many of the boundaries shown on this map are approximate because they are based on companies, not on strictly geographical boundaries. USEPA egrid2012 Version 1.0 p. 4

11 egrid subregion acronym egrid sub acronym Methods to NODetermine x season x SO 2 Emissions NO x season NO x SO Saved- 2 NO x season Average NO x SO 2 egrid subregion name (lb/mwh) (lb/mwh) (lb/mwh) (lb/mwh) (lb/mwh) (lb/mwh) (lb/mwh) (lb/mwh) (lb/mwh) Emissions Method (cont.): Egrid Sub-Region Average Emissions Rates egrid subregion name NO x (lb/mwh) Ozone AKGD ASCC Alaska Grid AKMS ASCC Miscellaneous AZNM WECC Southwest CAMX WECC California Year 2009 egrid Subregion Output Emission Rates - Criteria Pollutants ERCT ERCOT All Fossil fuel output Non-baseload output FRCC FRCC All Total output emission rates emission rates emission rates HIMS HICC Miscellaneous HIOA HICC Oahu Ozone season NO x (lb/mwh) SO 2 (lb/mwh) NO x (lb/mwh) Ozone season NO x (lb/mwh) SO 2 (lb/mwh) NO x (lb/mwh) Ozone season NO x (lb/mwh) MROE MRO East MROW MRO West SO 2 (lb/mwh) AKGD ASCC Alaska Grid AKMS ASCC Miscellaneous NEWE NPCC New England AZNM WECC Southwest CAMX WECC California NWPP WECC Northwest ERCT ERCOT All NYCW NPCC NYC/Westchester FRCC FRCC All HIMS HICC Miscellaneous NYLI NPCC Long Island HIOA HICC Oahu MROE MRO East NYUP NPCC Upstate NY MROW MRO West RFCE RFC East NEWE NPCC New England NWPP WECC Northwest RFCM RFC Michigan NYCW NPCC NYC/Westchester RFCW RFC West NYLI NPCC Long Island NYUP NPCC Upstate NY RMPA WECC Rockies RFCE RFC East RFCM RFC Michigan SPNO SPP North RFCW RFC West SPSO SPP South RMPA WECC Rockies SPNO SPP North SRMV SERC Mississippi Valley SPSO SPP South SRMV SERC Mississippi Valley SRMW SERC Midwest SRMW SERC Midwest SRSO SERC South SRSO SERC South SRTV SERC Tennessee Valley SRTV SERC Tennessee Valley SRVC SERC Virginia/Carolina SRVC SERC Virginia/Carolina U.S Ozone Ozone

12 5. Methods to Determine Emissions Saved- Marginal Emissions Analysis (MEA) The next slides focus on New England What you will see is the result of 10+ years of collaboration between air and energy regulators and ISO-NE Straight-forward approach, transparent assumptions Method is able to be adjusted to reflect market and economic conditions

13 Methods to Determine Emissions Saved-Marginal Emissions Analysis (cont.): Framing Questions What units are being displaced by EE? What fuel(s) are combusted? What variables influence what unit is marginal? Can simplifying assumptions be made?

14 Methods to Determine Emissions Saved-Marginal Emissions Analysis (cont.): ISO-NE Environmental Advisory Group Recognizes markets are not static Economics affect what fuels are combusted Analyzes peak and off-peak, and ozone vs. nonozone periods Methodology has evolved, informed by air regulator input Reference to recent work: mm/eag/mtrls/2012/apr202012/eag_mrgnl_em s_042012_v8.pdf

15 Methods to Determine Emissions Saved-Marginal Emissions Analysis (cont.): Factors Influencing Changes in Methodology Decreased natural gas prices Increased coal and oil prices Retirements of older electric generating uits Increased renewable generation Increased and cumulative energy savings from energy efficiency

16 Methods to Determine Emissions Saved-Marginal Emissions Analysis (cont.): Examples Three examples will be discussed A. Assume energy efficiency effects 500 MW of generation B. Existing: EE affects on the peak electric demand days C. Proposed: look at actual dispatch in any given hour Showing all three since the earlier methods may be applicable to other regions 16

17 7/19/2005 7/26/2005 7/27/2005 8/5/2005 8/11/2005 7/17/2006 7/18/2006 8/1/2006 8/2/2006 8/3/2006 6/26/2007 6/27/2007 8/2/2007 8/3/2007 8/8/2007 6/9/2008 6/10/2008 7/8/2008 7/9/2008 7/18/2008 Decremental NOx Emission Rate (lb/mwh) A. ISO- NE Hourly NO x Emission Rates for a 500 MW Generation Decrement from Peak with Elimination of Hydro Generation

18 7/19/2005 7/26/2005 7/27/2005 8/5/2005 8/11/2005 7/17/2006 7/18/2006 8/1/2006 8/2/2006 8/3/2006 6/26/2007 6/27/2007 8/2/2007 8/3/2007 8/8/2007 6/9/2008 6/10/2008 7/8/2008 7/9/2008 7/18/2008 Decremental NOx Emission Rate (lb/mwh) A. ISO-NE Hourly NO x Emission Rates for a 500 MW Generation Decrement from Peak with No Elimination of Hydro Generation

19 NOx (Tons per hour) B. New England 20 Peak Days Hourly NOx Emissions NOx Emissions from EPA & ISO Data for (5) Peak Load Days per Year: All time peak day Hour Peak Days: Yr/Mo/Day

20 NOx (Tons) B. Peak Hourly NOx vs. System Generation at Peak NOx Hour Peak Hourly NOx Rate = 4 lbs/mw (slope of line) ,500 23,000 23,500 24,000 24,500 25,000 25,500 26,000 26,500 Generation (MW) 20

21 NOx Rate - (lbs/mwh) NOx EMISSIONS RATES for ELECTRIC GENERATION UNITS IN CONNECTICUT Coal Residual Oil Distillate Oil Natural Gas

22 NOx Emissions (tons) Temperature (ºF) Methods to Determine Emissions Saved-Marginal Emissions Analysis (cont.):analysis by CT DEP: Relation between Ambient Temperature and Emissions Rate Daily NOx Emissions for Connecticut EGUs Sorted by Total Daily NOx Emissions (June 1, September 15, 2007) Diesel & Other Oil Residual Oil Pipeline Natural Gas Coal Hartford Max Temperature (ºF)

23 B. Methods to Determine Emissions Saved- Marginal Emissions Analysis (cont.)marginal Emissions Analysis Ozone / Non-Ozone Season Emissions (NOx) Air Emission Ozone Season Non-Ozone Season On-Peak Off-Peak On-Peak Off-Peak Annual Average (All Hours) NO X Annual Emissions (SO 2 and CO 2 ) Air Emission On-Peak Annual Off-Peak Annual Average (All Hours) SO CO able 5.6: 2010 Calculated New England Marginal Emission Rates (lb/mwh)

24 Proposed Calculation Method (Cont.) C. Methods to Determine Emissions Saved- Marginal Emissions Analysis (cont.):proposed MEA Method Annual Marginal Emission Rates 1. Identify all marginal units for each hour in the year of interest.. 2. Calculate the percentage share of each identified unit s emission contribution in each hour. 3. Sum percentages from #2, organized by month and marginal unit. 4. Multiply with the unit k s Emissions Rate m (lb/mwh) associated with a specific month. 5. Calculate #4 for all identified marginal units and sum those equivalent unit emissions for the year. 6. Calculate the annual marginal emissions rate by dividing by the number of hours in the year. 7

25 C. Methods to Determine Emissions Saved- Marginal Emissions Analysis (cont.): Results to be Results to Produced be Produced by Proposed Method. % of Time Marginal by Fuel Type Marginal Emission Rates (lb/mwh & lb/mmbtu) NO X : Annual, On-Peak and Off Peak during Ozone and Non-Ozone Season SO 2 : Annual, On-Peak and Off-Peak CO 2 : Annual, On-Peak and Off-Peak Marginal Heat Rate (MMBtu/MWh)

26 Comparison with 2010 Emissions Report Oil & Gas Units NO X,. NOx Non-Ozone Season Off-Peak NOx Non-Ozone Season On-Peak NOx Ozone Season Off-Peak NOx Ozone Season On-Peak NOx All Hours Emissions Rate (lb/mwh) Oil & Gas Units Emitting Units All Marginal Units 2010 Emissions Report 21

27 6. Methods to Determine Emissions Saved- Stochastic Approach Assesses impact of EE on actual generation without dispatch modeling Uses 8760 hours from one year of generation and actual dispatch Assumes future dispatch will behave similarly to the year chosen Apply quantity of EE to assess affect on generation 27

28 Methods to Determine Emissions Saved-Stochastic Approach(Cont.): Connecticut Example

29 Methods to Determine Emissions Saved-Stochastic Approach (cont):simplifying Assumptions for CT Use 2005 load shape, grow load to 2020 assuming similar weather patterns and fuel prices Assume that Connecticut s affect on ISO- NE (and vice versa) are similar in proportion to Connecticut s share of the region s load

30 Methods to Determine Emissions Saved- Stochastic Approach (cont.): CT EE Assumptions EE measures are applied across all hours EE programs reduce load by a constant percentage EE programs do not expire EE measures are cumulative and compounded

31 Methods to Determine Emissions Saved- Stochastic Approach(cont.): Stochastic Analysis Conclusions Simplifying assumptions facilitate analysis but effect precision The example discussed applies to Connecticut for a particular time period. Your results will be different EE programs are reducing NOx (and other pollutant) emissions today. Ramping up ( all cost-effective EE ) can achieve even more significant benefits

32 7. Methods to Determine Emissions Saved- Dispatch Modeling Typically completed by utility (e.g. IRP), transmission planners, EPA (IPM is a dispatch model) Results are economically driven (least-cost resources are dispatched first) Uses historical dispatch to forecast future dispatch based on input reference scenario and sensitivities Unit by unit results 32

33 Methods to Determine Emissions Saved- Dispatch Modeling (cont.) Applies the same principles discussed earlier on stochastic, but for several years Can also be done for a region (>one state) Results include: costs, emissions, number of hours each generating unit is expected to run

34 Methods to Determine Emissions Saved- Dispatch Modeling (cont.): Caveats Critical variables: load growth assumption, fuel price and forecast, construction costs EE is a dispersed resource with cumulative attributes. Many models require simplifying assumptions to assess affects 34

35 Methods to Determine Emissions Saved- Dispatch Modeling (cont.): Examples For more details, below are just a few examples: ter_option=displaced+emissions&advanced =false (link to several current and past reports) /suca/evaluation_guide.pdf gphaseiifinal.pdf

36 Concluding Thoughts: Using Emissions Data to Your Advantage Think about the emissions profile shown on the next slide What factors do you think are driving load increases in Connecticut? What do these tell you about ways in which the EE program might be structured or prioritized?

37 +7% MW = +93% NO X! 37

38 About RAP The Regulatory Assistance Project (RAP) is a global, non-profit team of experts that focuses on the long-term economic and environmental sustainability of the power and natural gas sectors. RAP has deep expertise in regulatory and market policies that: Promote economic efficiency Protect the environment Ensure system reliability Allocate system benefits fairly among all consumers Learn more about RAP at Chris James: cjames@raponline.org John Shenot: jshenot@raponline.org

39 Extra Slides if time permits The information gathered to determine the emissions benefits of EE can also be used to calculate other non-energy benefits Including the air quality and public health benefits (and avoided costs) can allow additional measures to be deemed costeffective, and increase the potential for future energy savings

40 CT Load Profile

41 Analysis for Montville 5

42 Emissions Analysis

43 Stochastic Model Results

44 CT NOx Emissions, 2% per year EE

45 Scenario Analysis to Meet Emissions Reductions Requirement

46 Air Quality and Health Benefits (1) EPA s BenMAP model: calculate change in morbidity and mortality from implementation of new policies National Academy of Sciences: Hidden Costs of Energy Epstein, et al Full Cost Accounting for Lifecycle of Coal

47 Air Quality and Health Benefits (2) BenMAP: free, desktop model that air staff can run. Little if any training required if proficient with computers. Hidden Cost : each kwh of coal poses average cost of 3.4 cents. Is as high as 12 cents per kwh in some areas Full Cost Accounting : total costs of coal normalized to kwh produced range from 9.36 to cents per kwh

48 Electric System and Reliability Benefits EE has many energy related benefits Energy efficiency, load management and clean demand response defer or avoid need for new transmission and generation Economic benefits include reducing the peak prices of electricity in a given hour or day

49 Electric System and Reliability Benefits Non-energy benefits were discussed earlier Avoiding transmission and distribution line losses: average is 6-8%. On peak days, such losses can be 20% Hourly electricity prices can exceed $1000 per MWh on peak days. Reducing the peak also reduces costs to consumers and utilities

50 Vermont Energy Efficiency Savings Value Updated Externality and NEB Values Most analyses of EE are woefully incomplete. $200 $180 $160 $140 $120 $100 $80 $60 $40 $20 $0 Risk DTQ NEB Other Fuel O&M Other Resources Externalities Avoided Reserves Line Losses Distribution Capacity Transmission Capacity Capacity Energy Some look only at avoided energy costs. Many include production capacity costs, but not transmission or distribution capacity. Few include other resource savings (water, gas, oil). Very few make any effort to quantity non-energy benefits. 50