Woodstove Manufacturers’Presentation to the Office ofManagement and BudgetSeptember 25, 20131Today’s Topics•Cost effectiveness of proposedstandards – NERA Presentation•Why lower standards are a “numbersgame” that will retard reductions inwoodstove PM.•NTTAA Test Method Concerns•What can we do?2•Lower standards ( e.g., 2.5 g/h or 1.3 g/h)based on current, dimensional lumber cribtesting is a “numbers game,” that creates onlyan illusion of progress.3Test Fuel4EPA Method 28 D. fir Dimensional Lumber Test Fuel CribNote: The bars represent the interior side walls of the stove.•Performance scores based on crib fuel testingdo not correlate with performance in homeswith “real” fuel (cordwood).–State air quality regulators have long complainedabout this problem.–A study by Dr. James Houck1comparing “field”performance data with certification (lab) datademonstrates that it is a real problem.51**A Comparison of Particulate Emission Rates from the In-Home Use of Certified Wood Stove Models with U.S. EPA** **Certification Emission Values and A Comparison between In-Home Uncertified and Certified Wood Stove Particulate** **Emissions**, Dr. James Houck, February 2012Houck Study - Major Conclusions•There is no correlation between certificationvalues and the real world emission rates.•And further, rank orders change.–A stove with a higher certification value mayperform better in the field than one with a lowercertification value.6Mean Emission Rate and EPA Certification Values by Coded Stove Model7There is no correlation betweencertification values and the in-situemission rates.**Source: A Comparison of Particulate Emission Rates from the In-Home Use of Cert ified Wood Stove Models with U.S. EPA Certification Emission** **Values and A Comparison between In-Home Uncertified and Certified Wood Stove Particulate Emissi ons** , Dr. James Houck, February 2012Mean Emission Rate and EPA Certification Values by Coded Stove Model8There is no correlation betweencertification values and the in-situemission rates.And further, rank orders change. A stovewith a lower certification value may notperform as well in the field as one with ahigher certification value.**Source: A Comparison of Particulate Emission Rates from the In-Home Use of Cert ified Wood Stove Models with U.S. EPA Certification Emission** **Values and A Comparison between In-Home Uncertified and Certified Wood Stove Particulate Emissi ons** , Dr. James Houck, February 2012•However, certified stoves do performsignificantly better than conventionalstoves (>50% PM reduction).910Mean PM Emission Rates for Uncertified Stoves and for Certified StovesGrouped by Low, Medium, and High EPA Certification Categories**Source: A Comparison of Particulate Emission Rates from the In-Home Use of Cert ified Wood Stove Models with U.S. EPA Certification Emission** **Values and A Comparison between In-Home Uncertified and Certified Wood Stove Particulate Emissi ons** , Dr. James Houck, February 2012The EPA certification values do notpredict the relative ranking of thestoves under real-world use.To smooth some of the inherent datavariability, stove models weregrouped by Low, Medium and Highcertification categories.11Mean PM Emission Rates for Uncertified Stoves and for Certified StovesGrouped by Low, Medium, and High EPA Certification Categories**Source: A Comparison of Particulate Emission Rates from the In-Home Use of Cert ified Wood Stove Models with U.S. EPA Certification Emission** **Values and A Comparison between In-Home Uncertified and Certified Wood Stove Particulate Emissi ons** , Dr. James Houck, February 2012The EPA certification values do notpredict the relative ranking of thestoves under real-world use.12Certified stoves do have substantiallylower particulate emissions underreal-world operating conditions.Mean PM Emission Rates for Uncertified Stoves and for Certified StovesGrouped by Low, Medium, and High EPA Certification Categories**Source: A Comparison of Particulate Emission Rates from the In-Home Use of Cert ified Wood Stove Models with U.S. EPA Certification Emission** **Values and A Comparison between In-Home Uncertified and Certified Wood Stove Particulate Emissi ons** , Dr. James Houck, February 201253% ReductionTest Method Precision•The precision of the crib wood test methodswill not allow us to reliably distinguishperformance differences in the range ofinterest.–Curkeet /Ferguson Precision Study•Study used EPA Accredited Laboratory ProficiencyRound-Robin Test Program Database•Study was conducted in accordance with ASTM E691which is the consensus standardized method fordetermining test method precision.13Conclusions from Precision Analyses ofthe EPA Laboratory Proficiency Data•The “within the same lab” precision of theweighted average emissionsat the 95%confidence level is at best ±2.9 grams per hourand typically about ±3.5 to ±5.4 grams perhour.•The “between labs” precision, at the 95%confidence level is ±4.5 to ±6.4 grams perhour.14Source: “**EPA Wood Heater Test Method Variability Study - Anal ysis of Uncertainty, Repeatability and** **Reproducibility based on the EPA Accredited Laborat ory Proficiency Test Database** ”, R. Curkeet and R.Ferguson. Submitted to EPA on October 6, 2011. Thereport is available upon request. The report wasalso summarized in Hearth and Home Magazine, March2011 Issue.•Variability in wood heater emissiontesting results for any given applianceismost likely a function of the randomnature of burning wood, no matterhow tightly you try to control theprocess.•Tightening test parameters (e.g., test fuelmoisture range) would simply increase costs,would not significantly improve precision andwould further widen the gap between labtesting and real world operation.15•Although it has been shown that EPA certified stoves asa groupperform substantially better in the field than conventional(uncontrolled) models, there is no predictable relationshipbetweenlaboratory test results using dimensional lumber cribs andrealworld performance for any given model.–Rank orders can change.•The test methods used to determine emission performanceare asomewhat blunt instrument – not capable of distinguishingperformance differences in the range of interest.•The random variability associated with burning wood is the primaryfactor in the poor test method precision.•NERA has shown that even if the emission reductions fromloweringthe emission limits were real and achievable in the field, thelowerlimits are not cost effective and have negative impacts on sales dueto increased prices.16•Increases in consumer retail price and thelikely decrease in the number of modelsavailable in the market will slow progress inchanging out the 6 million uncontrolled stovesstill in American homes.172010 National Particulate Emissions byFreestanding Stove CategoryCertified NonCat: 15,188Tons, 10%Certified Cat:5,016 Tons, 3%All Pellet: 1,445Tons, 1%Conventional135,420 Tons,86%186 Million +Stoves - 86% ofTotal PM~3.3 MillionStoves – 14%of Total PMTotal PM Emissions –2010: 157,069 TonsSource:**The Fraction of Freestanding Wood-Fueled Stoves in Current Use That are U.S. EPA** **Certified Cordwood Stoves and Wood Pellet Stoves**, Dr. James Houck, July 2011National Technology Transfer andAdvancement Act (NTTAA)•EPA must adopt ASTM consensus-based test methods forwoodstoves, because it cannot find that it would be “illegal” or“impractical” to do so under NTTAA.–ASTM test methods (which EPA participated in creating)•ASTM E2515 - measuring particulate in smoke•ASTM E2780 – fueling and operation during testing and dataaveraging todetermine performance rankings (“compliance algorithm”).•EPA plans to adopt the ASTM particulate measurement method, butplans to “Christmas Tree” the operating method in unsupportableways:–With an EPA substitute for the “low burn rate” criteria,which wereadopted to improve the real world performance of certified stoves.–With an EPA substitute for the compliance algorithm for Step 2/3standards, which has not been demonstrated to be achievable.19•The path forward here is clear:–EPA needs to adopt innovative approaches that will build a“bridge” to a different paradigm:•A program based on a cordwood test method that will produceanew generation of certified woodstoves with laboratoryperformance profiles that are better related to “real world”operating conditions.–Manufacturers are willing to work with EPA and otherstakeholders to develop such a program.•An ASTM Task Group is hard at work creating acordwood test method.–EPA and a number of state agencies are participating withmanufacturers and test laboratories in this effort, whichhopefully can be brought to a conclusion early in 2014.20What can be done?•Questions?•Thank you!21