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

Outline

• What are we testing for?

• Testing equipment

• Stove designs tested

• Results

What are we testing for? • Gas and particulate emissions that

impact health and the environment.

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

Particulate properties

Particulate properties

Black Carbon Organic Carbon

Flaming Events Smoldering Events

Outline

• What are we testing for?

•Testing equipment • Stove designs tested

• Results

Stove emissions testing equipment

The sampling probes

The sampling probes

Outline

• What are we testing for?

• Testing equipment

•Stove designs tested • Results

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

Uganda

Stove Tec

• Aprovecho design and construction

• Ceramic combustion chamber

• 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: Uganda

• Three Stone

• Often used outdoors

• 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

Outline

• What are we testing for?

• Testing equipment

• Stove designs tested

•Results

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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Particulatematter

Correlation between CO and PM test averages?

R² = 0.2812

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PM

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COEF

StoveTec

Correlation between CO and PM test averages?

R² = 0.0092

R² = 0.0013

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ImprovedNepalEco Fogon

Combustion Efficiency

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=𝐶𝑂2

𝐶𝑂2+ 𝐶𝑂

CO Emission Factor

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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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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

Questions?