Emission measurements from in-use cookstoves in four locations
Cheryl Weyant*, Yanju Chen, Justin Ellis, Christoph Roden, Tami C. Bond Partners at Berkeley Air, Aprovecho, PCIA, CRT Nepal, and First Energy
Ethos 2011 Nepal India Uganda Honduras
What are we testing for? • Gas and particulate emissions that
impact health and the environment.
• Carbon Dioxide
• Carbon Monoxide
• Particulate properties
Particulate properties • Total mass (g/kg fuel)
• Light scattering and absorption
• Elemental/Organic carbon ratio
Particulate properties • Total mass (g/kg fuel)
• Light scattering and absorption
• Elemental/Organic carbon ratio
• Elemental Carbon equals Black carbon (BC)
• Light absorbing particles
• Organic Carbon (OC)
• Light scattering particles
Stoves without Chimneys • Several similar stove designs
are combined in this category
• No statistically significant differences were found between stoves in this category.
• Wood fuel
Honduras
Honduras
Stoves with a Chimney
• Several stove designs are combined in this category
• No statistically significant differences were found between stoves in this category.
• Wood fuel
Nepal
Improved Chula • Variable homemade
construction
• Clay stove usually with one burner and one pot warmer
• Has a Chimney
• Wood fuel
India
Oorja • First Energy design and
construction • Battery powered fan
• Models with either ceramic
or metal combustion chambers
• Burns pellets made from compressed sugar cane bagasse
Traditional: Honduras
• Can have highly variable construction
• Sometimes has a plancha stovetop
• Wood Fuel
Traditional: India • Clay, homemade
construction
• Highly variable in size and design
• With or without chimney
• Used indoors
• Wood and dung fuel
Traditional: Nepal
• Clay, homemade construction
• Highly variable in size and design
• Wood fuel
• No chimney
Emissions are the result of a system
Fuel Type, moisture
User Attentiveness, skill
Demand Cooking task
Stove
A typical test
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CO2
CO
Particulate matter
Closer look at PM and CO
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CO
Particulatematter
Correlation between CO and PM test averages?
R² = 0.2812
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PM
EF
COEF
StoveTec
Correlation between CO and PM test averages?
R² = 0.0092
R² = 0.0013
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PM
EF
CO EF
ImprovedNepalEco Fogon
Combustion Efficiency
India Uganda Nepal Honduras 0.8
0.82
0.84
0.86
0.88
0.9
0.92
0.94
0.96
0.98
110 6 11 2 8 4 14 29 10
=𝐶𝑂2
𝐶𝑂2+ 𝐶𝑂
CO Emission Factor
India Uganda Nepal Honduras 0
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g C
O/k
g fu
el
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PM emission factors
India Uganda Nepal Honduras
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g /k
g fu
el
10 6 11 2 8 4 14 29 13
Using optical data: The tools
• Single Scattering Albedo (SSA): The amount of
scattering. Near 1 is very scattering, near zero is very absorbing.
SSA = Bsp / ext = Bsp /(Bsp+Babs)
• Absorption Ångström Exponent (AAE): How “picky” a particle is about the wavelength that is absorbed.
Using Optical data: Break it into bits
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Using optical data: Emission fingerprints
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SSA
AA
E
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Wav
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gth
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catt
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Emission profiles for different cookstoves in Honduras
high scattering, high pickiness from low combustion efficiency yellow or brown particles mainly from traditional cookstoves
low scattering, low pickiness from high combustion efficiency black particles come from ALL types of cookstoves
What next? • More field testing!
– We are looking for partner projects for emission studies.
• Extending the testing parameters
– Methane, Formaldehyde?, PAH?
• New particle optics sensor (Photoacoustic)
• Improve equipment durability and usability
• Unattended sensing/longer sampling sessions
• Brick Kiln emission testing
– Testing bigger, badder combustion