ENERGETIC OPTIMIZATION OF AN IMPROVED
COOKING STOVE FOR RURAL AREAS IN PERU
Work performed under the supervision of Prof. George Tsatsaronis and M.Sc. Natalia Realpe
Iulia Dolganova | SEER4ALL lecture series | 07.02.2017
Agenda
1. Introduction
2. Research question and objectives of the work
3. Theory
4. State of art
5. Possible solutions
6. Summary
7. Recommendations
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1. Introduction: background
In Peru, 34 % of the rural population uses solid fuels for cooking deforestation, health problems, etc. (INEI, 2015)
Open fire vs. traditional stove vs. improved cooking stoves (ICS)
Globalgrade (2014) Globalgrade (2014)
MEI (2014)
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1. Introduction: background
The Improved Cooking Stoves (ICS) Project of MicroEnergy International was implemented in rural areas
Implementation through microfinance mechanisms
access to good quality products for reasonable prices
Execution of market studies and validation tests
Three available models of ICS were tested in the beginning, one selected
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1. Introduction: ICS
ICS are designed in such a way to assist better combustion and heat transfer, for diminishing firewood use (in 30-35%) and for reducing intradomiciliary emissions
ICS must be safe to the end users, easy to use and guarantee low costs
ICS should be manufactured locally
Efficiency of an ICS: ηthermal, ICS = ηcombustion * ηheat transfer
ηcombustion larger than 90% (Aprovecho, 2002)
Increase ηheat transfer
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1. Introduction: problematization
Water Boiling Test. MEI (2014)
Variables Results
Initial temperature water in pot 1 [oC] 27,6
Initial temperature water in pot 2 [oC] 27,1
Time until the boiling of the pot 1 [min] 17
Boiling temperature of water in pot 1[oC] 99,2
End temperature of water in pot 2 [oC] 51,7
Efficiency of the system [-] 25%
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1. Introduction: problematization
Water Boiling Test. MEI (2014)
Variables Results
Initial temperature water in pot 1 [oC] 27,6
Initial temperature water in pot 2 [oC] 27,1
Time until the boiling of the pot 1 [min] 17
Boiling temperature of water in pot 1[oC] 99,2
End temperature of water in pot 2 [oC] 51,7
Efficiency of the system [-] 25%
Problem: The second pot
gets much less heat input
compared to the first one.
1. Pot: 0,91 kW
2. Pot: 0,52 kW
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2. Research question and objectives of the work
Is there an approach to improve the performance of the second pot without interfering majorly in the stove’s design and in such a way that it remains user friendly?
Main objectives:
1. Investigate the convective heat transfer in a prototype of
a Peruvian portable ICS with the help of experimentally
obtained data
2. Propose improvements to the stove’s performance by
enhancing the heat flow to the second pot
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3. Theory: heat transfer in a nutshell
Convection: matter dependent transport of mass, impulse or energy in flowing gas or liquids
Losses in the convective heat transfer: 22-39% of the total input to the woodstove (Zube, 2010)
Increasing convective heat transfer to the pot is the single most important way to increase thermal efficiency of a stove (Baldwin, 1985)
Increase
surface area Modify flow parameters
(mass flow rate,
temperature)
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4. State of art
Baldwin (1987) Heeden et al. (1986)
Kumar (1990) Bernilla (2005)
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5. Possible solutions
Social aspects
40% of families are not sure about the procedures to use an ICS (Peru, 2010). Risk of inacceptance
Improvement should be independent of extra user intervention/major change of habits
Economic aspects
80% earn less than 53 EUR/week (MEI, 2014)
Low payment willingness: 102 EUR
Production costs: 267 EUR
Respect local traditions, keep production costs low
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5. Possible solutions (1) – Elevation of the first pot
Idea: Elevation of the first pot, in order to diminsh the pressure losses of the system. Second remains submerged
Justification: A submerged first pot may block the flow to the second pot. Model „planchas“ delivered good results
Results:
Worse performance of the first pot (slower)
Lower losses in the system
Higher temperature of second pot (66 °C)
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5. Possible solutions (2) – Larger second pot
Idea: Increase the surface area of the second pot from 26 cm to 28 cm
Justification: Requests of the local population in the focus groups (MEI, 2014)
Results:
9% increase of the convective heat transfer to the second pot.
Pot hole larger as 28 cm is of no use for most households
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5. Possible solutions: (3) introduction of a baffle
Idea: Diminishment of the clearance height between both pots
Justification: Baffles reduce pressure losses to sudden expansion
Results:
Tpot2 7% higher than in the original prototype
Increase of 10% in the efficiency
Baffle size must be carefully planned and tested
0.102m
0.040m
0.062m
PAN I PAN II
BAFFLE
HEAT
Own design (2014)
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6. Summary
Proposed modifications
1st improvement: worse heat transfer to the first pot, no significant improvemnt of the second pot
2nd improvement: enlargment of the pot hole diameter is limited
3rd improvement: best potencial, baffle size must be carefully planned and tested many variables affect heat transfer in a stove
Zube (2010)
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7. Recommendations
More research on multipot ICS currently scarce literature
Peruvian regulation (2009) as model for neighbor countries (e.g. Bolivia): definition of temperature ranges to allow ICS certification
Field testing with a cook piece (Kitchen Performance Test)
Good practice measures: cut dry wood in small pieces and use lids
Decrease costs of the product without compromising its
quality access by means of microfinance mechanisms
Main objective of the ICS: guarantee a safe, affordable
and environmentally sustainable cooking process
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THANK YOU!
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Bibliography
Agenbroad, J.; DeFoort, M.: Kirkpatrick, A.; Cory K.. A simplified model for understanding natural convection driven biomass
cooking stoves – Part 1: Setup and baseline validation. Energy for Sustainable Development, Volume 15, Issue 2, June 2011.
Alvarez P.H.J. Estudio de cocinas mejoradas empleando leña y bosta como combustible. Tesis. Pontificia Universidad
Católica del Peru. Facultad de Ciencias e Ingeniería. Lima, Perú, 2009.
Aprovecho Reasearch Center. Design Principles for Wood Burning Cook Stoves. Shell Foundation. Partnership for Clean
Indoor Air. Cottage Grove, USA, 2002.
Baldwin, S. F. Biomass stoves: Engineering Design, Development and Dissemination. Center for Energy and Environmental
Studies. Princeton University. Princeton, New Jersey, USA, 1987.
Bejan, A.; Tsatsaronis, G.; Moran, M. Thermal Design & Optimization. John Wiley & Sons, 1996.
Bernilla, J.H. Diseño de un prototipo de cocina mejorada para la zona andina de la provincia de Ferreñafe. Tesis.
Universidade Nacional “Pedro Ruiz Gallo”, Facultad de Ingeniería mecánica y eléctrica. Lambayeque, Perú, 2005.
Heeden, D.J. v.d.; Sulilatu, W.F.; Krist-Spit, C.E. The effect of baffles on the performance of the Nouna wood stove. In:
Technical Aspects of woodburning stoves. Eindhoven University of Technology, 1983, Pages 43-82.
De Lepeleire, G; M. Christiaens. Heat Transfer and woodstove modelling. Proceedings of the Indian Academy of Sciences
Section C: Engineering Sciences, March 1983, Volume 6, Issue 1, Pages 35-46.
L’Orange, C.L.; DeFoort, M.; Wilson, B. Influence of testing parameters on biomass stove performance and development of
an improved testing protocol. Energy for Sustainable Development, Volume 16, Issue 1, March 2012, Pages 3–12.
Incropera, F.P.; DeWitt, D.P.; Bergamn, Lavine. Fundamentals of Heat and Mass Transfer. Wiley, 2007.
INEI. Resultados del Censo Nacional de Población y vivenda. Lima, Perú, 2015.
Kraume, M. Energie-, Impuls- und Stofftransport II. Tecnische Universität Berlin, Fachgebiet Verfahrenstechnik, Berlin, 2012.
Kshirsagara, M.P.; Kalamkarb, V.R. A comprehensive review on biomass cookstoves and a systematic approach for modern
cookstove design. Renewable and Sustainable Energy Reviews. Volume 30, February 2014, Pages 580–603.
Kumar, M; Kumar S.; Tyagi, S.K. Design, development and technological advancement in the biomass cookstoves: A review.
Renewable and Sustainable Energy Reviews, Volume 26, October 2013, Pages 265–285.
Iulia Dolganova| SEER4ALL lecture series | 07.02.2017
Seite 19
Bibliography
Kumar, R; Lokras, S.S., K.S. Jagadish. Development, analysis & dissemination of a 3-pan cookstove. Bangalore: Karnataka
State Council for Science and Technology, 1990.
MicroEnergy International GmbH (MEI). Estudio de Mercado. Cocinas Mejoradas Portátiles. Internal document. Berlin, 2014.
Muñoz, M. Perú: Empoderando a las mujeres desde las cocinas. Heifer Perú. Available under:
http://www.heiferperu.org/npw/index.php/es/articulos-2/item/5-peru-empoderando-a-las-mujeres-desde-las-cocinas/ Last
accessed: April 2014.
Munson, B.R.; Young, D.F.; Okiishi, T.H. Fundamentals of Fluids Mechanics. Fourth Edition. NY: John Wiley & Sons, 2002.
Okafor, I.F. ; Unachukwu, G.O. Performance Evaluation of Nozzle Type Improved Wood Cook Stove. American-Eurasian
Journal of Sustainable Agriculture, 6(3): 195-203, 2012.
Perú. Estudio Comparativo: Medición de la Contaminación Intradomiciliaria (PM2.5 y CO) y Consumo de Combustible de
Cocinas Tradicionales y Mejoradas. Zonas de Intervención de la Asociación Civil Los Andes Cajamarca. Lima, Noviembre del
2010.
Polifke, W.; Kopitz, J. Wärmeübertragung: Grundlagen, analytische und numerische Methoden. München: Pearson, 2009.
Prasad, K. K. (Ed.). Some studies on open fires, shielded fires and heavy stoves. Woodburning Stove Group, Technische
Hogeschool Eindhoven, 1981.
Ragland, K.W.; Bryden, K.W.; Combustion Engineering. 2nd edition. FL, Boca Raton: CRC Press, 2011.
Sencico. Reglamento para la evaluación de la cocina mejorada. Available under:
http://www.vivienda.gob.pe/dnc/archivos/Estudios_Normalizacion/Normalizacion/normas/ReglamentoGINCocinasMejoradas.pdf
. Last accessed: March 2014.
Smith, K.R. Health, Energy and Greenhouse-Gas Impacts of Biomass Combustion in Household Stoves. Energy for
Sustainable Development, 1994, Pages 23-29.
World Health Organisation (WHO). Five keys to safer food manual. 2006. Available under:
http://www.who.int/foodsafety/publications/consumer/manual_keys.pdf. Last accessed: April 2014.
Zube, D. Heat transfer efficiency of biomass cookstoves. Master Thesis. Colorado State University, Department of Mechanical
Engineering. Fort Collins. 2010.
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Extras
MEI (2014)
Weekly income of the participants (February 2014)
0%
3%
0%
0%
33%
47%
14%
3%
Less than 100 PEN
101 - 200 PEN
201- 300 PEN
301 - 400 PEN
401 - 500 PEN
501 - 600 PEN
More than 601PEN
Unkwown/unsure