Policy Analysis pubs.acs.org/est
How You Count Carbon Matters: Implications of Differing Cookstove Carbon Credit Methodologies for Climate and Development Cobenefits Olivia E. Freeman†,§ and Hisham Zerriffi*,‡ †
Institute of Resources, Environment and Sustainability, University of British Columbia, 2202 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada ‡ Liu Institute for Global Issues, University of British Columbia, 6476 NW Marine Drive, Vancouver, British Columbia V6T 1Z2, Canada S Supporting Information *
ABSTRACT: The opportunity to apply for carbon credits for cookstove projects creates a source of funding that can be leveraged to promote the “win-win” environmental and development benefits of improved cookstoves. Yet, as in most environment-development efforts, unacknowledged trade-offs exist under the all-encompassing “win-win” claims. This study therefore compares different scenarios for calculating cookstove carbon credits, including comparing different types of stoves using different fuels, different methodologies and theoretical scenarios to account for a range of climate-relevant emissions. The results of the study highlight the following: 1) impacts of different assumptions made within carbon credit methodologies, 2) discussion around potential trade-offs in such projects, and 3) considerations needed to truly promote sustainable development. The Gold Standard methodology was more comprehensive in its accounting and generally calculated more carbon credits per scenario than the Clean Development Mechanism methodology. Including black carbon in calculations would be more reflective of climaterelevant stove emissions and greatly increase the number of credits calculated. As health and other development benefits are not inherently included in carbon credit calculations, to achieve “win-win” outcomes, deliberate decisions about project design need to be made to ensure objectives are met and not simply assumed.
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INTRODUCTION
the development of extensive markets for improved cookstoves.11,13 As with other development-environment initiatives framed as “win-win”, there are inherent trade-offs between maximization of potential benefits.11,14−16 Simon et al. (2012)11 provides an overview of such “win-win” nuances for carbon financed cookstove projects and stress that “win-win” climate and development benefits are not automatically achieved through carbon financed cookstove projects. A key issue in achieving such win-win benefits is the number of carbon credits potentially generated by cookstove projects. This is important both because it determines the levels of carbon credit revenues and it may also influence how cookstove interventions are implemented, including influencing the choice of technology. Carbon credits are generated through specific market mechanisms that have specific rules around allowable
Roughly 40% of the global population relies on household burning of solid fuels (e.g., wood or coal) to meet their cooking needs. The resulting emissions have significant effects on both human health and the climate in addition to other environmental and nonenvironmental impacts (e.g., local forest health, time spent collecting wood, etc.).1−5 Cookstove projects that can reduce or eliminate solid fuel use,2,3 thereby reducing both household air pollution emissions4 and greenhouse gas (GHG) emissions,5−7 are framed as “win-win” climate and development projects and have gained traction globally. This includes increased international investment in pro-poor cookstove companies and organizations, the creation of a major international public-private partnership, the Global Alliance for Clean Cookstoves,8 the launch of the United Nations Secretary General’s Sustainable Energy for All Initiative,9 and the opportunity to apply for carbon credit funding. Cookstove projects are viewed as being one of the few carbon credit project types that directly promote sustainable development.10−12 Furthermore, carbon financing is seen as a key resource for solving some of the financial difficulties preventing © 2014 American Chemical Society
Received: Revised: Accepted: Published: 14112
January 29, 2014 November 4, 2014 November 18, 2014 November 18, 2014 dx.doi.org/10.1021/es503941u | Environ. Sci. Technol. 2014, 48, 14112−14120
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Table 1. List of the 11 Stoves in This Study, Including Details about the Location the Stove Is Used, a Brief Description of the Stove Itself, and Thermal Efficiency and Amount of Fuel Used for Each Stove stove codea
W-Im-U W-Im-V W-Pat-V W-Gas-U W-Fan-U
India17/ Mexico18 India17 China19 Mexico18 India21 Philip’s Stove21
Coal-U Coal-V Char-U Ker-U LPG-U
China19 China19 India23 India17/China19 India17/China19
W-Tr-U
a b
location
thermal efficiency
description
estimated fuel use (t/yr)b
energy densities (TJ/t)b
traditional “three-stone” stove or hand built mud stove
18%17
2.69
0.015 (wood)17
unvented, free-standing metal wood stove brick wood stove with a chimney masoned wood stove with chimney unvented, free-standing, top-feed, gasifying wood stove unvented, free-standing, Philip’s “Fan” wood stove with battery powered fan unvented, metal coal stove metal coal stove with chimney unvented, free-standing basic charcoal stove unvented, free-standing kerosene wick stove unvented, free-standing liquid petroleum gas stove
23%17 24%19 24%20 32%21 40%21,22
2.07 2.02 2.06 1.53 1.21
0.015 0.015 0.015 0.015 0.015
(wood)17 (wood)17 (wood)17 (wood)17 (wood)17
14%17 17%19 18%19 50%17 54%17
1.87 1.54 1.58 0.34 0.30
0.027 0.027 0.026 0.043 0.046
(coal)19 (coal)19 (charcoal)17 (kerosene)17 (LPG)17
“U” refers to unvented stoves, while “V” refers to vented stoves (i.e., including a chimney or flue that moves the emissions outside the home). Values taken from Grieshop et al., 20115 with original sources of data cited where relevant.
that are included in Grieshop et al. (2011)5 “GWC-All” scenario were also included in the carbon credit calculations in order to theoretically demonstrate the potential impact of a more complete accounting of climate-forcings. These calculations were made using the framework of the two carbon credit methodologies, though neither methodology accounts for these additional species at this time. The rest of this section describes the following: the different stoves, the two carbon credit methodologies and emission factor values included in the analyses, and an overview of the analyses included in this study. Stove Types. An “improved” cookstove is a widely used term that refers to any stove which is “improved” relative to the previous technology that it is replacing (mainly traditional “three-stone” fires or other open combustion fires). They are usually characterized by reduced fuel consumption, increased combustion efficiencies and/or reduced emission levels of particulate matter and climate forcing species. Within this general definition sometimes distinctions are made between basic models of biomass stoves, biomass stoves which gasify the fuel and stoves which burn modern fuel such as liquid petroleum gas (LPG) or kerosene. In this paper reference to improved cookstoves include all above-mentioned categories of cookstoves. Eleven stoves are included in this study (Table 1). These can be roughly grouped into six categories based on similarities in thermal efficiency, amount of fuel use, and fuel type: traditional biomass stove (W-Trad-U), basic improved biomass stoves (WIm-U, W-Im-V, W-Pat-V), gasifying biomass stoves (W-Gas-U, W-Fan-U), coal-fueled stoves (Coal-U, Coal-V), charcoalfueled stove (Char-U), and the cleaner burning liquid fossil fuel stoves (Kero-U, LPG-U). In this study the stoves are referred to both individually and in these loosely defined groups. For all the analyses the baseline stove was assumed to be a traditional stove (W-Trad-U). Therefore, all the calculations of emission reductions are when switching from the W-Trad-U to one of the other ten stoves outlined in Table 1. Two Carbon Credit Methodologies: The Clean Development Mechanism (CDM) and The Gold Standard (GS). Carbon markets were developed to provide an economic mechanism to incentivize the reduction of emitted GHGs. Carbon credits are tradable units each representing the
credit generation and how credits are calculated. This then has implications for how trade-offs are made. This research, therefore, examines some of the specifics in the calculations of carbon credits by comparing two different methodologies, the Clean Development Mechanism (CDM) and the Gold Standard (GS). Carbon credit generation is then discussed in three main contexts: (1) the impact of methodology on carbon credit generation; (2) methodological considerations within the calculations; and (3) implications of methodology limitations for overall development and climate benefits of carbon credit cookstove projects (including the impact on carbon credit generation when a more extensive set of climate forcings is included). Through these analyses, this work touches on debates about the technicalities of carbon accounting, integration of measures for promoting sustainable development through carbon credit projects, and some of the benefit trade-offs involved in implementing cookstove projects under a carbon credit framework. The results of this work hold relevance for climate mitigation and adaptation, environmental management, public health and development policies.
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METHODS Overview. Carbon credits are calculated under a number of different scenarios to compare the following: a) performance of different stove types, b) differences in two main carbon credit methodologies for cookstove projects, and c) the limitations in the current main methodologies to encompass comprehensive climate impacts of cookstove projects. The comparison of these different scenarios sheds light on how climate benefits of cookstove projects are being represented, the differences in climate benefits between different stove types and the corresponding development implications. Drawing on work by Grieshop et al. (2011),5 this study employs the same stoves used in their analysis. Some of the emission factors (EFs) used here differ as the original studies were revisited, and the best fit EFs were not always the same as used in Grieshop et al. (2011).5 Instead of emulating their methods to calculate direct stove emission reductions, the CDM and the GS methods were used to calculate carbon credits as an estimate of potential atmospheric reductions of climate forcing species, which is used as a proxy to represent potential climate impacts. Additional climate-forcing species 14113
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conservative estimates without requiring the actual measurement of the baseline stove’s EFs, but does not reflect the actual emission reductions. It is also important to note that the CDM does not allow fossil fuel based stoves (e.g., LPG) to obtain credits unless switching from a high to low carbon intensive fossil fuel (e.g., coal to LPG). Therefore, in the reported results there are two numbers included for the coal, charcoal, LPG, and kerosene stoves: zero for the actual credits possible under the CDM and a second value for the credits, if switching from a traditional biomass-based baseline stove to fossil fuel stove was allowed. Details of the equations for both methodologies are included in the Supporting Information. CDM vs GS. Carbon credits calculated under the two different methodologies for the ten different stove scenarios are referred to as “Allowable Credits”. Approximately how much can be earned per scenario (which again measures number of carbon credits per stove per year) was also calculated employing the prices found in Table 2. The average price per carbon credit was used for all project types under the CDM for the CER credits and the average price specifically for cookstove projects for the VER credits. This is only an approximation, and actual prices and income may greatly vary from the ones provided here.
reduction of 1 tonne of carbon dioxide (CO2) equivalent (tCO2e) that can be used to offset emissions. They can be bought and sold in two types of carbon markets, the regulated and the voluntary markets. Cookstove projects are one of the many projects that can become carbon credit certified when switching from a baseline to a project technology. The credits produced are based upon the amount of nonrenewable fuel use that is reduced and, in some cases, also on the reduction of emissions of GHGs during the combustion process. Currently there are two main methodologies by which cookstoves projects are certified to sell carbon credits: the CDM method24 and the GS method.25 Created as a tool to help Annex 1 countries meet their Kyoto Protocol targets in the most cost-effect way, the CDM accredits emission-reduction projects in developing countries with certified emission reductions (CER) credits.26,27 Due to the lack of strong and unified efforts to realize development benefits alongside emission reductions, the CDM has been criticized for not addressing the sustainable development component of their mandate.28−33 In comparison, the GS framework specifically aims to provide high levels of sustainable development.34,35 This strong commitment to sustainable development outcomes in addition to emission reductions is attractive to many different types of buyers and, in theory, earns a premium on the market. The GS framework can be used to certify both CERs for the regulated market or voluntary emission reduction (VER) credits sold and traded in the unregulated voluntary carbon market. The GS CER credits are jointly certified under the CDM and GS using CDM calculations and methodology, but require the extra GS certification steps to ensure a higher quality credit. The VER credits are calculated using a GS developed methodology, which has a number of significant differences in comparison to the CDM methodology. In this study the GS method refers specifically to the GS methodology for calculating GS VER credits. Emission Factors. All EF values were measured from water boiling tests (WBTs), a common measure to determine stove performance based upon heat transfer and combustion efficiency (22for a description of WBTs). Though this does not provide representative measures of actual EFs during cooking in homes, it provides a consistent measure to compare all the stoves against. Stoves used within the home likely have higher EFs than those reported through WBTs, especially for particulate matter with an aerodynamic diameter less than or equal to two and a half microns (PM2.5),18 a key pollutant influencing health impacts of household air pollution.5,36,37 See Table S1 in the Supporting Information for a complete table of EFs. Estimating Climate Impacts: Carbon Credits. All emissions calculated are in tCO2e per year per stove, where one tCO2e equals one carbon credit. For both equations, CO2 emitted from burning renewable biomass is not included as it is assumed to be carbon neutral, with the amount of carbon emitted being resequestered through forest regeneration. This assumption is reflected through the inclusion of the fraction of nonrenewable biomass ( f NRB) variable in both equations, which was assumed to be 75% (see the Supporting Information for a sensitivity analysis of f NRB values). Both equations differ in their method of credit calculation. GS25 includes CH4 and emissions associated with fuel production where CDM24 uses a weighted mixed fossil fuel based default emission factor. This is meant to provide
Table 2. Average Prices of VER and CER Credits in 2011 and 2012: All Project Types vs GS Projects vs Cookstove Projectsa average prices per credit VER CER
2012 2011 2012 2011
all projects
GS projects
cookstove projects
$5.90 $6.20 (accessed August 08, 2011). (28) Olsen, K. H. The clean development mechanism’s contribution to sustainable development: a review of the literature. Clim. Change 2007, 84, 59−73. (29) Bumpus, A. G.; Cole, J. C. How can the current CDM deliver sustainable development? WIREs Clim. Change 2010, 1, 541−547. (30) Cosbey, A.; Parry, J.-E.; Browne, J.; Babu, Y. D.; Bhandari, P.; Drexhage, J.; Murphy, D. Realizing the development dividend: Making the CDM work for developing countries (phase I report). International Institute for Sustainable Development 2005, 1−72. Available at (accessed Aug 08, 2011). (31) Figueres, C. Sectoral CDM: Opening the CDM to the yet Unrealized Goal of Sustainable Development. Int. J. Sustainable Dev., Law Policy 2006, 2, 1−20. (32) Pearson, B. Market failure: why the Clean Development Mechanism won’t promote clean development. J. Clean. Prod. 2006, 15, 247−252. (33) Sterk, W.; Wittneben, B. Enhancing the clean development mechanism through sectoral approaches: definitions, applications and ways forward. Int. Environ. Agreements 2006, 6, 271−287. (34) Drupp, M. A. Does the Gold Standard label hold its promise in delivering higher Sustainable Development benefits? A multi-criteria comparison of CDM projects. Energy Policy 2011, 39, 1213−1227. (35) Gold Standard. What we do. 2011. Available at < http://www. cdmgoldstandard.org/What-we-do.64.0.html> (accessed August 08, 2011). (36) Sinton, J. E.; Smith, K. R.; Peabody, J. W.; Yaping, L.; Xiliang, Z.; Edwards, R.; Quan, G. An assessment of programs to promote improved household stoves in China. Energy Sustainable Dev. 2004, 8, 33−52. (37) Naeher, L. P.; Brauer, M.; Lipsett, M.; Zelikoff, J. T.; Simpson, C. D.; Koenig, J. Q.; Smith, K. R. Woodsmoke Health Effects: A Review. Inhalation Toxicol. 2007, 19, 67−106. (38) Peters-Stanley, M.; Yin, D. Maneuvering the Mosaic State of the Voluntary Carbon Markets 2013. Ecosystem Marketplace and Bloomberg New Energy Finance 2013, 1−126. (39) Smith, K. R.; Uma, R.; Kishore, V.; Zhang, J.; Joshi, V.; Khalil, M. Greenhouse implications of household stoves: an analysis for India. Annu. Rev. Energy Environ. 2000, 25, 741−763.
Canadian Institutes of Health Research (CIHR) Strategic Training Fellowship.
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