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# Total Projected Particulate Emissions from New Fireplaces in the Fifth Year from NSPS Effective Date

Presented for the Hearth, Patio & Barbecue Association Fireplace Caucus

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# Purpose of the Analysis

• Compare estimated particulate emissions from fireplaces 5 years after the effective date of an NSPS to estimated particulate emissions from fireplaces if an NSPS that includes fireplaces isn’t promulgated.3 

# Information Needed 1. Projected number of new housing starts.

‐ This is the primary multiplier for the overall analysis. 

# 2. Percentage of new houses with fireplaces broken down by: a. Gas Fireplaces b. Wood

‐ burning Fireplaces i. Those used for heating. ii. Those used for aesthetic enjoyment. iii. Those not used at all.

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# 3. Wood Fireplace Fueling Information: a. Amount of wood used in fireplaces per year: i. In new fireplaces used for heating. ii. In new fireplaces used for aesthetic enjoyment. 

# 4. Emission factors for new fireplaces: a. “Baseline” fireplaces. b. NSPS fireplaces (Assumed EPA Phase 2)5 

# Where do we get this information?

• Some of the information is available directly from a variety of sources of published literature (surveys, studies, etc.)

• Some of the information must be derived from more complex analyses combining information from multiple sources.

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# Projected Number of New Housing Starts

• Three different approaches. 1. Assume the 10

‐year average for the period from 1996 – 2005. 2. Assume the 10

‐year average for the period from 2000
‐ 2009. 3. Apply housing start recovery slope from the 1995 – 2005 period to the 2009 housing start value to project the ho using starts in 2016.7 *Average annual housing starts for the period 2011 to 2016 base d on the slope of 1995 to 2005 housing starts and an intercept ba sed on 2009 housing starts.

8 New Single-Family Housing Starts Projection Basis Cumulative New WBFPw/oI by Use Category Installed from 2011 to 2016

Heating Aesthetics Not Used ’96-’05 Pre-Downturn

Ten-Year Average 112,135 700,150 378,360 ’00-’09 Ten-Year Average 101,382 633,011 342,079 ’95-’05 Slope + ’09 Intercept

Projected Average ’11-’16 57,167 356,944 192,892 Note: WBFPw/oI = Wood

‐ burning fireplaces without inserts9 

# Percentage of New Houses with Wood Fireplaces 1. From survey information: a. Determine the percentage of new houses with one or more fireplaces. b. Determine the percentage of those fireplaces that are gas fireplaces. 

# 2. Calculate the percentage of wood burning fireplaces by subtraction of the gas fireplaces.

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# 3. From survey information, determine the percentage of fireplaces used for heating. a. Survey information co mbines wood and gas. b. Apply a gas fireplace use preference factor (from study) to account for the increased use preference for gas fireplaces over wood fireplaces.

‐ This is needed to determine the percentage of fireplaces used for heating that are gas since we don’t have a direct estimate of gas versus wood usage for fireplaces used for heating. 

# 4. Calculate the percentage of wood burning fireplaces used for heating by subtracting the gas fireplaces used for heating.11 

# 5. Calculate the number of wood burning fireplaces used for aesthetic enjoyment or not used at all by su btraction of the wood burning fireplaces used for heating.

• From survey information and calculation, determine the percentage of wood burning fireplaces that are not used at all.

• By subtraction, calculate the percentage of wood burning fireplaces that are used for aesthetic enjoyment.

• From survey information, determine and apply a multiple fireplace per house factor.

12 Fireplace Ownership in New Construction (% of Single

‐ Family New Construction Homes, Multiple Ownership Factor of 1.17 Not Considered in Chart) Wood

‐ Burning Fireplace Usage in New Construction (% of Wood

‐ Burning Fireplaces)13 Value Reference(s) * Usable Fireplaces (2007) 50.81% † 6 Percent Gas Fireplaces (2008) 65.43% 99

‐ 103 Calculated Usable WBFPw/oI 1 17.57% †

‐ FPw/oI Used for Heating (2007) 7.7% † 6 Gas Fireplace Usage Preference Factor (2008) 1.2 110 Calculated WBFPw/oI Used for Heating 2 1.65% † (9.42%) ‡

‐ Calculated WBFPw/oI Used for Aesthetics or Not Used 3 15.91% †

‐ Average Percent of Unused WBFPw/oI 31.78% 104

‐ 108, 111
‐ 114 Calculated WBFPw/oI Not Used 4 5.58% † (31.78%) ‡

‐ Calculated WBFPw/oI Used for Aesthetics 5 10.33% † (58.80%) ‡

‐ Multiple Ownershi p Factor 1.17 108
‐ 110 * See “References” section for full citations. † Percent of New Construction homes ‡ Percent of usable wood

‐ burning fireplaces 1 (Usable Fireplaces, New Construction) x (1 – Fraction of Gas Fireplaces) 2 (FPw/oI Used for Heating) x (1 – Fraction of Gas Fireplaces) x (Gas Fireplace Enrichment Factor) 3 (Usable WBFPw/oI) – (WBFPw/oI Used for Heating) 4 (Usable WBFPw/oI) x (Average Fraction of Unused WBFPw/oI) 5 (WBFPw/oI Used for Aesthetics/Not Used) – (WBFPw/oI Not Used)

Summary of Analysis/Wood Burning Fireplaces in New Construction

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# Wood Burning Fireplace Fueling Information 1. From survey information: a. Determine the average cordwood use for wood burning fireplaces used for heating. b. Determine the average cordwood use for wood burning fireplaces used for aesthetic enjoyment. 

# 2. From literature: a. Assign the average dry mass for a cord of wood.15 

# Emission Factors for New Fireplaces 1. From literature, determine baseline average fireplace (factory built and masonry) emission factor for cordwood – 11.3 g/dry kg. 2. Assume a Voluntary Program Phase 2 average emission factor for NSPS fireplaces – 5.1 g/dry kg. 3. Factor in wood

‐wax firelog use.

16 Value Reference * Average Cordwood Use in WBFPw/oI, Heating 0.656 cords/year 117 Average Cordwood Use in WBFPw/oI, Aesthetic 0.069 cords/year 117 Average Dry Mass of Cordwood 1.23 tons/dry cord 118 Emission Factor, Cordwood, Phase II 5.1 g/kg, 5G

‐ Emission Factor, Cordwood, Baseline 11.3 g/kg, 5G 132 Firelog Percentage † 25% 110 Average Firelog Use 16 firelogs/year 116 Average Firelog Weight 4.74 lb/firelog (dry) 116 Emission Factor, Wax

‐ Fiber Firelog (Emission Rate) 21.2 g/kg, 5G (15.69 g/h) 119

* See “References” for full citations. † Fraction of homes that use their fireplace for aesthetics and normally burn firelogs. It is assumed that the overwhelming majo rity of firelog use is aesthetic. 

## Summary of Wood Burn ing Fireplace Fueling Data and Emission Factors17 

# 5 th 

# – Year Emissions Projections 1. By calculation, project the 5 th 

# – Year emissions from baseline and NSPS fireplaces using the three housing start projections. 2. Average the three results to give the final values.

18 New Single-Family Housing Starts Projection Basis Emission Factor Projected Tons of Particles Emitted in 2016 Heating Wood Aesthetics Total Wood Firelogs * ’96-’05 Pre-Downturn

Ten-Year Average Phase II 538 265 164 968 Baseline 1,193 588 1,945 ’00-’09 Ten-Year Average Phase II 487 240 148 875 Baseline 1,078 531 1,758 ’95-’05 Slope + ’09 Intercept

Projected Average ’11-’16 Phase II 274 135 84 493 Baseline 608 300 991 Average Phase II 433 213 132 779 Baseline 960 473 1,565 

## Total Particulate Emissions for New Construction Houses with Wood

‐ Burning Fireplaces withou t Inserts Emitted in 2016

*The wax

‐fiber firelog emission factor remains the same in both emission factor scenarios.19 

# Sensitivity Analysis – Increased

Penetration of Gas Fireplaces

• Over time, the percentage of gas fireplaces has been increasing.

• Increasing the cost of wood burning fireplaces with the addition of emission control technology is likely continue or accelerate that trend.

• The sensitivity case evaluates the projected 5 th



# ‐ Year emissions if the gas fireplace proportion of new fireplaces increases by 10 percentage points (~65% to ~75%).

20 Percentage of New Fireplaces that are Gas-Fired Emission Factor Projected Tons of Particles Emitted in 2016 Heating Wood Aesthetics Total† Wood Firelogs * 65.43% Gas Fireplaces Phase II 433 213 132 779 Baseline 960 473 1,565 75% Gas Fireplaces Phase II 202 163 101 466 Baseline 447 361 909 

## Total Particulate Emissions for New Construction Houses with Wood

‐ Burning Fireplaces withou t Inserts Emitted in 2016 Sensitivity Analysis, Gas

‐ Fired Fireplace Proportion of New Fireplaces Increased from 65.43% to 75%

*The wax

‐fiber firelog emission factor remains the same in both emission factor scenarios. †Total values based on average of new single

‐family housing starts projections as shown in previous table.