Lifecycle Assessment (LCA) of Lifecycle Assessment (LCA) of Coal Burning for Home Heating Coal Burning for Home Heating on the Navajo Nation, USAon the Navajo Nation, USA
29 July 2011 29 July 2011
WHO Training on Life Cycle Assessment WHO Training on Life Cycle Assessment Ministry of Health, UlaanbaatarMinistry of Health, Ulaanbaatar
Anne Riederer ScD ([email protected]) Anne Riederer ScD ([email protected]) American Association for the Advancement of American Association for the Advancement of Science (AAAS) Fellow, Office of Research and Science (AAAS) Fellow, Office of Research and Development, U.S. Environmental Protection AgencyDevelopment, U.S. Environmental Protection Agency
A traditional Navajo home A traditional Navajo home “hogan”“hogan”
1908 photo of hogan with Ship Rock in distance1908 photo of hogan with Ship Rock in distance(source: Denver Public Library)(source: Denver Public Library)
Summer hogan - early 1900sSummer hogan - early 1900s
(source: Denver Public Library)(source: Denver Public Library)
Traditional hogans nowadaysTraditional hogans nowadays
Traditional hogans todayTraditional hogans today
Traditional octagonal hogan near Shiprock (abandoned) around 1950-70?
source: www.nationalgeographic.com
Traditional hogan in wintersource: http://navajopeople.org/navajo-hogans.htm
Modern hogansModern hogans
Modern hogan
Modern wooden hogan
Inside a modern hogan – look familiar?Inside a modern hogan – look familiar?
(source: www.rehobothbhs.org)
Other modern Navajo homesOther modern Navajo homes
source: www.nativenewsnetwork.com/american-recovery-reinvestment-act-funded-22-new-homes-on-the-navajo-nation.html
source:www.rjnconstructionmanagement.com/Job_Photos.html
source:www.rjnconstructionmanagement.com/Job_Photos.htmlsource: http://bettycauler.com/page/Navajo-Nation.aspx
Home of the future?Home of the future?
source: www.dwell.com
Old and new household energy sourcesOld and new household energy sources
(source: http://www.azcentral.com/photo/News/Projects/19220)
Cold winters (maybe not as cold as here!)Cold winters (maybe not as cold as here!)
• 18,000 of 48,000 Navajo homes without electricity
• In USA, 14.2% of Native American households have no access to electricity compared to 1.4% of all US households
• Navajo Nation accounts for 75% of US households without electricity
Source: Navajo Tribal Utility Authority. 2004. Source: Navajo Tribal Utility Authority. 2004. Navajo Electrification Navajo Electrification Demonstration Program.Demonstration Program. Presentation to U.S. Department of Energy, Presentation to U.S. Department of Energy, Tribal Energy Program 2004 Program Review Meeting, Colorado, USA.Tribal Energy Program 2004 Program Review Meeting, Colorado, USA.
Coal-Fired Power Plants on Navajo NationCoal-Fired Power Plants on Navajo Nation
• Navajo Generating Station (Page, Arizona)
• Four Corners Power Plant (2,040 MW) (Farmington, New Mexico)
• Together serve 600,000 families in Arizona, Nevada, California (not on Navajo Nation)
• Proposed plant at Desert Rock (will it get Proposed plant at Desert Rock (will it get built?); all power would be exportedbuilt?); all power would be exported
• ~600,000 billion BTU coal exported from ~600,000 billion BTU coal exported from Navajo Nation each year Navajo Nation each year (Mills, 2006. as cited in (Mills, 2006. as cited in Billie et al.)Billie et al.)
• Navajo Nation gets large share (30-85%) of Navajo Nation gets large share (30-85%) of its revenues from coal salesits revenues from coal sales
Source: Navajo Tribal Utility Authority (NTUA). Navajo Electrification Demonstration Program. Presentation at Department of Energy, Tribal Energy Program, 2004 Annual Meeting
Source: Navajo Tribal Utility Authority (NTUA). Navajo Electrification Demonstration Program. Presentation at Department of Energy, Tribal Energy Program, 2004 Annual Meeting
Source: NTUA. Navajo Electrification Demonstration Program. Presentation at Department of Energy, Tribal Energy Program, 2004 Annual Meeting
Economic RealitiesEconomic Realities
• Average household income on Navajo Nation much lower than rest of U.S.
• 40% unemployment
• Running a power line to a home costs ~ $30,000 per mile (Billie et al. 2008. SAND Number 2009-0074P)
• Hybrid system of 880 Watt photovoltaic (PV) array and small wind turbine provided by NTUA cost ~$18,000 each; family must manage load carefully since units produce ~2 kW per day (Billie et al. 2008. SAND Number 2009-0074P)
Other off-grid heating options (coal, wood, propane)Other off-grid heating options (coal, wood, propane)
source: http://cronkitenewsonline.com/2010/10/for-many-navajos-its-been-a-long-wait-for-power/Source of cost information: “Burning coal for heat puts families at risk, but many on Navajo land see few options,” http://iapnews.wordpress.com/author/envhealth/
Modern Coal HeatersModern Coal Heaters
Why are we doing the Navajo coal heating LCA?Why are we doing the Navajo coal heating LCA?
Bunnell et al. 2010. Journal of Environmental and Public Health
Why are we doing the Navajo coal heating LCA?Why are we doing the Navajo coal heating LCA?
Paul Anastas, EPA Assistant Administrator for Research & Development
Navajo coal heating LCANavajo coal heating LCA
Interpretation
Goal and ScopeDefinition
Inventory
ImpactAssessment
Options consideredOptions considered
Start with coal…
…present preliminary results to stakeholders. Then they will decide 2-3 other options we should consider.
Interpretation
Goal and ScopeDefinition
Inventory
ImpactAssessment
Inputs Outputs
Figure X. System boundaries of the Navajo home heating life cycle assessment (LCA) – Version 1 (5/2/11)
System boundaries
Production phaseProduction phase Use phaseUse phase End of life phaseEnd of life phase
Heating unit Heating unit manufacturemanufacture
TransportationTransportation
Raw material Raw material acquisitionacquisition UseUse
Refurbishment/reuseRefurbishment/reuse
MaintenanceMaintenance
Monitoring/testing/ Monitoring/testing/ certificationcertification
TransportationTransportation
Demolition/demanu-Demolition/demanu-facturing/recyclingfacturing/recycling
Final disposalFinal disposal
Emissions/ Emissions/ effluents/ effluents/
wastewasteLand/water/ Land/water/ carbon usecarbon use
Raw materialsRaw materials
Renewable Renewable energyenergy
Local job Local job opportunitiesopportunities
Non-renewable Non-renewable energyenergy
Waste heatWaste heat
Goal and ScopeDefinition Setting the Functional UnitSetting the Functional Unit
HEED (Home Energy Efficient Design) Model
• UCLA Dept of Architecture and Urban Design
• www.aud.ucla.edu/energy-design-tools
Goal and ScopeDefinition Setting the Functional UnitSetting the Functional Unit
500 32,413 65 9,500 19660 b 40,546 61 11,833 18
1,012c 63,932 63 18,737 191,508c 91,581 61 26,841 182,004c 121,960 61 35,744 18
a Home Energy Efficient Design (HEED) Model (available: http://www.energy-design-tools.aud.ucla.edu/; accessed 25 Apr 2011). b Approximate average size of Shiprock home (see Table 1). c HEED Model permits home size to be specified in 4 ft x 4 ft grid squares, thus 1,012, 1,508 and 2004 ft2 were modeled instead of 1,000, 1,500 and 2,000 ft2, respectively.
TABLE 2. Results of HEED 4.0a simulation of annual heating energy requirements for typical Shiprock homes, by size
kBTU kBTU/ft2 kWh kWh/ft2Home size (ft2)
Variable
Response
%a Mean SD Median Min Max
Point estimate for
LCAb
Number of rooms 94.2 5.7 2.3 6 1 13 6 roomsHighest wall height (ft) 93.4 8.4 1.3 8 5.8 16 8 feetLowest wall height (ft) 38.7 7.7 0.5 8 6.3 9.4 8 feetAverage wall height (ft) 54.7 8.1 0.7 8 6.5 10 8 feet
Gap at top of wall? 98.5 yes = 26.7% no = 73.3% insulation=moderate
Ventilation rating 97.8 poor = 15%, moderate = 77%, good = 42% insulation=moderate
Kitchen length longest 88.3 13.3 3.5 13 2.8 24 13 feet shortest 38.7 7.8 3.9 8 2.0 19 8 feet average 33.6 11.5 3.2 10.9 6.0 18 11 feet - USE THIS #Kitchen width longest 88.3 11.5 3.2 11.0 2.4 23.8 11 feet shortest 36.5 6.6 2.5 8.0 1.0 11 7 feet average 33.6 9.4 2.0 10.0 5.2 15.3 10 feet - USE THIS #Kitchen height highest 90.5 8.3 1.4 8.0 6.5 14.8 8 feet lowest 37.2 7.5 0.7 7.9 4.0 8.5 8 feet average 43.1 8.0 1.4 8.0 6.0 17.1 8 feet
a% of participants answering this question of N=137 total survey participants. bValue to be used in determining functional unit for the EPA/Dine College Life Cycle Analysis (LCA) of Coal Use for Home Heating on the Navajo Nation.
TABLE 1. Estimation of typical household dimensions in the Shiprock Area of the Navajo Nation, 2008 heating season (Data source: Bunnell JE and Garcia LV. 2008. Results of a Survey of Residential Home Heating Fuel and Stove Type and Use in the Shiprock Area of the Navajo Nation. Open-File Report 2008–1249. Reston, VA: U.S. Geological Survey.)
TYPICAL HOUSEHOLD DIMENSIONS (based on above assumptions) = 6 rooms @ 11 x 10 x 8 feet/room
= 6 rooms x 880 ft3 = 5,280 ft3 of house to heat; ALTERNATIVELY, 6 rooms @ 11 x 10 ft2 = 6 110 ft2 rooms
= 660 ft2 home
Interpretation
Goal and ScopeDefinition
Inventory
ImpactAssessment
Inputs Outputs
Figure X. System boundaries of the Navajo home heating life cycle assessment (LCA) – Version 1 (5/2/11)
System boundaries
Production phaseProduction phase Use phaseUse phase End of life phaseEnd of life phase
Heating unit Heating unit manufacturemanufacture
TransportationTransportation
Raw material Raw material acquisitionacquisition UseUse
Refurbishment/reuseRefurbishment/reuse
MaintenanceMaintenance
Monitoring/testing/ Monitoring/testing/ certificationcertification
TransportationTransportation
Demolition/demanu-Demolition/demanu-facturing/recyclingfacturing/recycling
Final disposalFinal disposal
Emissions/ Emissions/ effluents/ effluents/
wastewasteLand/water/ Land/water/ carbon usecarbon use
Raw materialsRaw materials
Renewable Renewable energyenergy
Local job Local job opportunitiesopportunities
Non-renewable Non-renewable energyenergy
Waste heatWaste heat
We are starting here because this is where the health impacts are likely to be greatest
How much Shiprock coal = 40,546 kBTU?How much Shiprock coal = 40,546 kBTU?(functional unit = heat for 1 family for 1 year)(functional unit = heat for 1 family for 1 year)
From Bunnell et al. (2010): "The free coal comes from the Late Cretaceous Fruitland Formation and is relatively low rank (subbituminous to high-volatile bituminous). The Fruitland coal is lower in calorific value (10,646 +/− 1590 BTU/pound) and higher in ash content (22.24 +/− 7.02%) than…Black Mesa (10,910–11,560 BTU/pound, 4.7–9.1%)…Many people who live in the … Shiprock area, despite having access to free coal from the Navajo mine, nevertheless choose to purchase Black Mesa coal at local fleamarkets due to its superior quality…"
Coal type % use Avg BTU/lb Source Fruitland 50 10,646 Bunnell et al. 2010 Black Mesa 50 10,910 Bunnell et al. 2010
Weighted average: 10,778
Fuel requirement 3,762 lbs 1,706 kg
1.9 tons (short)
Interpretation
Goal and ScopeDefinition
Inventory
ImpactAssessment
TRACITRACITool for the Reduction and Assessment of Chemical and other environmental Impacts
Ozone DepletionGlobal Warming
Eutrophication
Inventory of StressorsChemical EmissionsFossil Fuel UseLand UseWater Use
Impact CategoriesOzone DepletionGlobal WarmingAcidificationEutrophicationSmog FormationHuman Health CriteriaCancerNoncancer
EcotoxicityFossil Fuel UseLand UseWater Use
…….
Characterization (e.g., Eutrophication)
0
100
200
300
400
500
600
700
800
Product A Product B Product C
End of Life
Use
Processing
Transportation toManufacturing Site
Raw Material Acquisition
BUT! TRACI does not yet handle indoor air pollution – we have to fix that...the Navajo LCA can be a test case
(TRACI graphic courtesy of Jane Bare, EPA/ORD)
What are emissions from burning 1.9 What are emissions from burning 1.9 tons Shiprock coal in a stove?tons Shiprock coal in a stove?
AP-42
www.epa.gov
How reliable are emissions factors?How reliable are emissions factors?
How reliable are emissions factors?How reliable are emissions factors?
Source: EPA. 1995. Introduction to AP 42, Volume I, Fifth Edition (Source: EPA. 1995. Introduction to AP 42, Volume I, Fifth Edition (www.epa.gov/ttn/chief/ap42/index.html)
Emissions factors for residential Emissions factors for residential coal combustioncoal combustion
Source: Haneke, “A National Methodology and Emission Inventory for Residential Fuel Combustion.”
• S = weight % sulfur content of coal as fired (example: if fuel is 1.2% sulfur, then S = 1.2)
• On average, for bituminous coal, 95% of fuel sulfur is emitted as SO2 Source: AP-42, 5th edition, Table 1.1-19
Sulfur content of Navajo CoalSulfur content of Navajo Coal
www.usgs.gov
Mean sulfur content:- Black Mesa coal = 0.5%- Fruitland coal = 0.9%- Midpoint value = 0.7%
Emissions factors for residential Emissions factors for residential coal combustion – other pollutantscoal combustion – other pollutants
Pollutant Emission Factor AP-42 Table Publication (lb/ton) (hand-fired) Date
HCl 1.2 1.1-15 09/98HF 0.15 1.1-15 09/98CH4 5 1.1-19 09/98CO2 72.6*mean %C 1.1-20 09/98
PAHs (polycyclic aromatic hydrocarbons)PAHs (polycyclic aromatic hydrocarbons)
Source: EPA. 1984. Emissions factors for residential wood and alternatives combustion.
Source: EPA. AP-42, 5th edition.
Source: EPA. AP-42, 5th edition.
Emissions inventory so far (still working on it!)Emissions inventory so far (still working on it!)
Emissions to air Value Units Reference Year
Total lbs 1 Navajo functional
unit
Total kg 1 Navajo
functional unit
Carbon dioxide 4,450 lbs/ton AP-42 Table 1.1-20 1998 8,371 3,801
Carbon monoxide 275 lbs/ton AP-42 Table 1.1-3 1998 517 235
NOx (unspecified) 9 lbs/ton AP-42 Table 1.1-3 1997 17 8
Particulates (PM10) 6 lbs/ton AP-42 Table 1.1-4 1997 12 5
Sulfur dioxide 22 lbs/ton AP-42 Table 1.1-3 1998 41 19
HCl 1 lbs/ton AP-42 Table 1.1-15 1997 2 1
HF 0 lbs/ton AP-42 Table 1.1-15 1997 0 0
Methane 5 lbs/ton AP-42 Table 1.1-19 1998 9 4
VOC (unspecified) 9 lbs/ton AP-42 Table 1.1-19 1998 17 8
Carbon dioxide 2,598 lbs/ton EPA wood stv (oak) 1984 4,886 2,218
Carbon monoxide 73 lbs/ton EPA wood stv (oak) 1984 137 62
NOx (unspecified) 6 lbs/ton EPA wood stv (oak) 1984 3 1
Particulates (PM10) 1 lbs/ton EPA wood "particulate" 1984 2 1
Sulfur dioxide 1 lbs/ton EPA wood stv (oak) 1984 2 1
COAL STOVES
OLD WOOD STOVES
Emissions factors for old wood (oak) stovesEmissions factors for old wood (oak) stoves
TRACI impacts so far (still working on it!)TRACI impacts so far (still working on it!)
Global Warming Air (kg CO2 eq)
Ozone Depletion Air
(kg CFC-11 eq)
Smog Air (kg O3 eq)
old coal stove 3,801 0 4,565
old wood stove 2,218 0 256