Role of processed fuels in cooking energy transitions Abhishek Kar1*, Sumeet Mohanty2, Lokendra Singh1, Anupama Arora1, Ibrahim Hafeezur Rehman1, Ram Chandra Pal1 1 The Energy and Resources Institute, New Delhi, India 2 Indian Institute of technology, Kharagpur, India * Corresponding Author firstname.lastname@example.org +91-9899972727 Abstract In the backdrop of a dominant regime of direct combustion of fuel wood and agricultural residue as cooking fuel, a transition experiment on processed fuel is being carried out in a village in India by The Energy and Resources Institute (TERI) supported by Government of India. Direct combustion of low density agricultural residues leads to significantly low energy yield per unit volume of biomass consumed. It is “expected” that a value chain for processed fuel (through densification of agricultural residue to yield high energy density low volume mass through Pelletization process) catering to cooking fuel need of rural households can contribute to sustainability transition. In the context of renewed interest in improved stoves, processed fuel (pellets) can “improve” performance of such stoves because of consistency in size, energy content, and moisture level resulting in increased fuel efficiency along with reduction in indoor air pollution. Many households in developing countries are forced to purchase fuel wood to supplement their non-monetized biomass fuel supply. Hence, pellets can potentially become a commercially sustainable substitute to the existing traditional fuel wood market regime. Further, biomass like fallen leaves, which otherwise remains unutilized and rots in the open creating a threat to public health, can be utilized as feedstock for pellet. Conceptualized as an experimental project related to sustainable transition, Strategic Niche Management (SNM) framework has been used to “understand” the innovation and identify its strengths and short-comings by understanding the interaction between three internal niche processes. Keywords: fuel processing, biomass, pellet, rural energy, SNM 1.0 Introduction: One of the key concerns in related to transitions to more a sustainable energy sector has been fuel and technology switching in rural households of the developing world (Rehman et al., 2010). Without access to modern cooking and heating energy technologies and fuel, domestic households are forced to use unprocessed solid biomass in traditional mud stoves (Ravindranath and Balachandra, 2009). It is felt that while renewed interest in research and investment in cooking devices is pertinent (Venkataraman et al., 2010), it is also worthwhile to focus on processing of biomass which can further “improve” performance of these stoves for rural households (Rehman et al., 2010, Sharma, Mukunda and Sridhar, 2009). Romjin, Raven and Visser (2010) have raised concerns on sustainability challenges of “structural over-usage” of unprocessed biomass for meeting household energy needs which is characterized by low efficiency and negative public health and environmental impacts (Ravindranath and Balachandra, 2009). The Energy and Resources Institute (TERI) has undertaken an “experimental project” (Kemp, Schot and Hoogma, 1998) involving research, production and dissemination of pellets (processed biomass based cooking fuel) targeted at rural households in Uttar Pradesh state of India with financial support from Government of India in 2010. With potential to contribute to sustainable development, the experiment has been conceptualized as a “sustainability experiment” and analyzed in this paper using the Strategic Niche Management (SNM) framework to “understand” the innovation (Witkamp, Raven and Royakkers, 2010). To this end, the paper gives an overview of the dominant regime and landscape factors (section 2) and an introduction to the pelletization technology and its significant social and environmental benefits (section 3). In section 4, analyses of the dynamics played by the three inter-related processes which are important for niche development (Berkhout et al., 2010) in context of the project is carried out apart from describing the “protection” offered under the experiment (Raven, 2005). In conclusion (section 5), the paper builds a case for about the need for further research in pelletization technology and implementation of multiple pelletization projects to create a technology niche which in the long run can contribute to sustainable transition. 2.0 Existing regime characteristics- wide spread unprocessed solid biomass usage as cooking fuel: Across the developing world, women are dependent on collected or purchased biomass as cooking fuel. Non-monetized cooking fuel comprises of fuel wood -defined by Saxena (1997) as fallen wood, smaller pieces, twigs, wood shavings, saw dust, bark and roots which have no alternative applications, unutilized (not suitable either as feed or fodder) agricultural by-products like rice straw, mustard stalk etc., and dried cattle manure is used as cooking fuel by rural households in India and across the developing world (Ravindranath and Balachandra, 2009). Increasingly, more and more households are also forced to purchase hardwood due to scarcity of fuel wood in vicinity. This existing bioenergy based cooking regime is “dominated” by a combination of structures, culture and practices such as lack of cash surplus and absence of reliable supply/access to enable switch over to modern fuels like LPG or processed biomass based fuel (Raven, Bosch, and Weterings, 2007, Ravindranath and Balachandra, 2009). About 85% of India’s 159 million rural households and 21.5% of 63 million urban households use solid un-processed bio-fuels in traditional mud stoves for cooking purpose (Parashar et al., 2005, NSS, 2010). Such cooking practice is characterized with incomplete combustion resulting in emission of pollutants such as particulate matter (PM), carbon monoxide (CO), nitrogen & sulfur oxides (NOx and SOx) and other toxic compounds including poly-aromatic hydrocarbons (PAHs) (Smith et al., 2005) which mostly occurs inside poorly ventilated kitchens in rural areas across developing countries (Desai et al, 2004). Indoor air pollution (IAP) increases risk of pneumonia, acute lower respiratory infections (ALRI) among children under 5 years and chronic obstructive pulmonary disease (COPD) among adults over 30 years of age (Arcenas et al, 2010, Rehfuess et al., 2006). Approximately half a million premature deaths and nearly 500 million cases of illness are estimated to occur annually as a result of exposure to smoke emissions from biomass use by households in India (UNDP/ ESMAP, 2003). It has also been reported that women and children spend significant time in collection of cooking fuels which have negative health and safety implications (World Bank, 2003). 3.0 Alternative to existing regime: Pelletization as a form of biomass processing 3.1 Continued dependence on biomass fuels: Considering IEA (2007) estimates that dependence on unprocessed solid biofuels for cooking is expected to continue in foreseeable future (632 million Indians estimated to be dependent in 2030) in conjunction with expected population explosion (and consequent stress on natural resources), it is imperative to look into biomass fuel processing for such rural households (Rehman et al., 2010). 3.2 Biomass processing: Biomass processing in the context of cooking fuel for households involves low cost densification low grade fuel wood (Saxena, 1997), agricultural residues and other bio-waste such as fallen leaves to develop a fuel block which can be “cleanly” combusted to extract energy for cooking or heating application (Sharma, Mukunda and Sridhar, 2009). One of the most common densification process is known as pelletization which, as defined by Mani (2005) is a mechanized method of densifying biomass such that the bulk density becomes more than 500 kg/m3 and the moisture reduces to about 8% on a wet basis. Manufacturing of pellets involves drying of biomass, grinding, and the pelleting processes. Pelletization of biomass waste and its emergence as competitor to purchased fuel wood may be envisioned as a transition from this existing “dominant regime” of unprocessed biomass usage as cooking fuel. While research on fuel densification has been carried out earlier (Saxena, 1997), the scope of research was targeted at heating applications for processing industries. Under this transition experiment, the focus is on densification of locally available low cost biomass for usage as household cooking fuel in a decentralized manner. 3.3 Characteristics and advantages of pelletization: During a given task of boiling water in a forced draft stove, performance of pellets was compared with hard wood purchased locally for various aspects such as reduction in indoor air pollution and reduction in fuel feeding iterations. The results are discussed in relevant sections related to the advantages of pelletization. 3.3.1 Improved combustion of pellets reduces emission: Fuel characteristics like packing density of the fuel and moisture content also affect emissions during combustion (Sharma, Mukunda and Sridhar, 2009, Atkins et al., 2010). Processed fuel, in form of pellets, are generally more suitable for burning in stoves because of greater density, consistency in size, and lower moisture level thus reducing emissions. Exposure of cook to black carbon concentration, which is an important indicator of indoor air pollution, reduced by 50% when pellets were used in lieu of wood. 22.214.171.124 Size: Atkins et al (2010) indicated that homogeneous size distribution of wood fuel can significantly increase combustion efficiency. Further, smaller wood pieces (difficult to chop manually) with higher surface area to volume ratio expedites burning as more fuel surface area is exposed to the combustion chamber temperature resulting greater heat absorbance per unit time (Yang et al., 2005). A survey commissioned by TERI in the project area indicated that manually chopped wood pieces (greater than 10 cm in length, 5 cm in width and 3 cm in height) are used for cooking in rural households. TERI pellets have homogeneity in shape (cylindrical) and size (2 cm length and 1 cm diameter) resulting in improved combustion. 126.96.36.199 Low Moisture content: Atkins et al. (2010) has reported that biomass with high moisture content emits significant amounts of smoke before it can burn properly, as the fuel temperature is unable to attain the requisite high combustion temperatures quickly. Gathered biomass or even purchased hardwood has high moisture content in comparison to pellets which being produced though a mechanized exothermic process has moisture content less than 10% (Shokansanj and Felton, 2006). Greater the moisture content in the fuel during combustion more will be the heat of combustion1 which is waste energy as it converts the moisture to water vapor and does not contribute to cooking thereby reducing energy efficiency (Van Loo and Koppejan, 2006). TERI pellets have average efficiency of 9% to 11% during packing. 3.3.2 Usage of waste biomass: Ravindranath and Balachandra (2009) estimated that the total agro-residue production in India exceeded 450 Mtons/year out of which the biomass available for energy purposes amounts to 150 Mtons out of which only 11% is being utilized. Surplus and unused biomass is usually burnt in the open field, causing air pollution. Pelletization of the un-utilized biomass locally and its usage as clean burning cooking fuel will create a local level market for the waste biomass, providing an incentive to farmers to sell their unused biomass, instead of burning it. Biomass sources like fallen leaves of mango and mahua trees which have no food or fodder value have been utilized in pellet production. TERI pellets have 45% saw dust, 5% rice husk and 25% fallen leaves and the rest of previous cycle pellet powder residue and binders. 3.3.3 Easy of usage 188.8.131.52 Reduced fuel feed iterations: Chin and Siddiqui (2000) established an empirical relationship between die pressure applied during biomass densification (which implies increasing packing density2 of the densified biomass known as pellet or briquette) and combustion rate in a standard combustion 1 Moisture content increases the specific heat capacity of the fuel because additional amount of heat is required to vaporize the water present thereby taking more time to reach ignition temperature leading to poor combustion in initial burning period. 2 Packing density simply refers to the mass per unit volume of the solid, in this case the fuel device. It is observed that as die pressure increases, it leads to a decrease in the combustion rate and hence increase residence time. TERI pellets require 14% less fuel charges for a given task in comparison to hard wood purchased from local market. 184.108.40.206 Easy handling and storage: Past research (Bergmann, 2005; Mani, 2005) suggests that pellets, unlike raw biomass have a high packing density hence, rigidity which leads to lower transportation costs as well as less handling problems, thereby making it an ideal fuel for domestic stoves. Lehtikangas (1999) has reported that biomass pellets are less susceptible to biological decay in comparison to unprocessed biomass due to lower moisture content, thereby prolonging their storage period. 4.0 Application of SNM framework to assess success potential of the experimental project: While SNM has been traditionally been used to analyze historical case studies “in retrospective” it has a role of technology management strategy of ongoing projects (Raven, Bosch, and Weterings, 2007). Transition literature identifies three interrelated processes - voicing and shaping of expectations, network formation and learning & articulation that influence the potential success of the introduction of an innovation (here, pelletization) in the context of niche development (Raven, 2005). In the following sections, each of these three processes has been discussed in the context of this ongoing experimental project apart from highlighting how the experimental project was offered protected space. 4.1 Voicing and shaping of actor expectations: Like any other experimental project, actor expectations about commercial potential of pellets played an important role in the early stages of the experiment which enabled investment of resources (including time and money) when no market existed for pellets (Raven, 2005). Playing the role of an action research organization, TERI has been instrumental in voicing concerns (“articulating expectations” in context of SNM) about biomass scarcity and the urgent need to explore biomass based fuel processing for household cooking fuel in different forums in terms of technology development and commercial sustainability. As suggested by Raven, Bosch, and Weterings (2007), it attracted attention and resources of policy makers and government. As a result, the project sponsor- GoI believed in the societal, economic and environmental benefits of decentralized fuel processing and its commercial potential and hence agreed to generously fund a pilot demonstration project. The village entrepreneur, a businessman, believed in the shared (with TERI) vision of a potential market for low cost pellet produced from locally available waste biomass and shared initial project cost. However, it should be noted that “protection” by project funds in terms of substantially covering capital costs lowered entrepreneur’s risk exposure (Raven, 2005). Initially demonstration and trials for various combinations (of raw materials) for pelletization was carried out over a period of three months involving 0.4 tonnes of pellets across 150 households. In helped in voicing and shaping of expectation in terms of: 4.1.1 Identification of target customer: During the first round of user trials actors were encouraged to express their opinion of the commercial potential of these products. It was communicated by the end users (actors who are critical for sustainability of such initiatives) during first round of trials that pellets will be purchased only by those households who purchase hard wood from market to meet entire fuel need or to supplement their gathered biomass. Families using nonmonetized biomass gathered locally articulated their decision of not intending to switch over to monetized pellets irrespective of its current and future benefits. Hence, the initial entrepreneur (actor) expectation of catering to rural households became more “specific” (Hoogma, 2000) in terms of catering to only those “households who purchase fuel wood” where subsequent user trials were conducted. 4.1.2 Creation of price ceiling: During user trials in 45 such households, majority of end users articulated there inability to spend more than their then current expenses for cooking fuel irrespective of its characteristics like lesser smoke. Such price sensitivity created a price ceiling of 100 USD/tonne for pellets which then was the rate of locally available hard wood making pricing expectation more “specific” which led to re-structuring of pellet composition. 4.1.3 Positive response during trials: As more experiments (user trials) supported expectations (of a comparatively clean burning and easy to use fuel at the same price of hard wood), “quality” of expectations increased (Raven, 2005; Hoogma, 2000). During user trials as both end users expressed willingness to purchase pellets and the entrepreneur being confident of producing pellets within the price ceiling. 4.1.4 Increased demand for user trials: Almost 120 more end users who purchase hardwood expressed interest to be part of user trials and insisted on getting “samples” before they make purchase decisions. It created more “robust” user expectations about pellets as “larger number of relevant actors shared the same expectation” (Raven, 2005) of ‘commercial potential of pellets.’ As suggested by transition scholars, this process of “articulating” and “negotiating” shared expectations provided direction to the experiment (Witkamp, Raven and Royakkers, 2010). As a result, almost 100 households, who earlier used locally purchased hard wood as cooking fuel, have switched over to pellets (repeat purchase) within a period of six months having purchased more than 1100 kg at market price (zero subsidy) of USD 1000 per tonne as on 31st November 2010. Overall, it may be deducted that experimental project had fairly specific and quality expectations which were growing increasingly robust increasing the chance of successful niche development (Hoogma, 2000). 4.2 Actor network formation: The importance of creating networks in terms of reducing complexity, scale, investments, risks, and uncertainty by involving actors from different domains in the project has been extensively highlighted in transition literature (Mourik and Raven, 2006; Raven, Bosch, and Weterings, 2007). Under this experimental project, conscious decisions were taken to actively engage multiple actors besides TERI, entrepreneur and end users as it improves the scope of niche development (Raven, 2005) in the following ways: 4.2.1 Identify and sensitize potential actors to be part of the network: TERI has made conscious efforts to ensure than potential stakeholders from societal, policy and technology domains like key policy makers and global development institutions like UNDP and DFID officials are aware of the vision and activities of this experimental project through periodic briefings and site visits. TERI also requests project sponsor to undertake multiple mid-term project reviews as the review team consist of subject experts and influential policy makers who can potentially play active role in the network. Publications and dissemination of information (like presentation of this paper in this conference on ‘Innovation and sustainability Transitions in Asia’) regarding this project is also being carried out to get expert inputs. However, it is felt that there is need to more actively engage local public representatives and community leaders. 4.2.2 Continuous engagement and cross relation amongst network actors: End user and production teams used to interact on a regular basis during user trials. However, reluctance of entrepreneur to get in touch with end users post-sales has been reported and corrective actions are currently being taken. Further, cross-relation between actors, sans TERI, has been almost absent which can be a major hurdle in improvement of network alignment (Raven, 2005). In conclusion, the existing actor network is heavily TERI dependent with low cross relationship between other actors which requires corrective action. 4.3 Learning processes: Learning in the context of SNM is focused on the changes executed in the process of the experiment (technology development, actor interaction etc.) which is aimed to couple with opportunities and overcome oppositions/barriers in the environment outside of the local project for better functioning of the innovation (Mourik and Raven, 2006). Under the project, three key learning processes as mentioned by Raven, Bosch, and Weterings (2007) have been discussed below in context of the experimental project: 4.3.1 Techno-economic optimization: In order to keep the pellet production cost within the price ceiling set (please refer to 4.1.2), the composition of pellet was significantly modified. The proportion of relatively expensive biomass like rice husk (costing 55 USD/ tonne) was reduced from 25% to 5% while proportion of freely available fallen leaves (collection cost of 22 USD/ tonne) was increased from 5% to 25%. As Raven, Bosch, and Weterings (2007) suggested, such adjustment of technology to increase chance of successful diffusion. 4.3.2 Alignment between technical and social aspects: Berkhout et al. (2010) has highlighted the importance of alignment of user preferences with technology specifications. Raven (2005) has also highlighted the important role played by users in the learning process of an experimental project which is demonstrated in the following section in terms of “negotiating” the packaging type. 220.127.116.11.1 Packaging: During the first round of sales, the pellets were packaged in 25 kg sacks which lowered per unit cost of packaging and distribution. It was reported that some households required 15-20 days to consume the pellets. Because most rural households have damp conditions due to thatched house, the pellets absorbed moisture and performed poorly in later stage. By early next year, pellets will also be sold in 5kg jute bags. This has also triggered unintended add-on benefit of higher demand as consumers without significant cash surplus prefer the smaller packs. 18.104.22.168.2 Ignition Style: User feedback pointed out to difficulty in ignition of pellets and requirement of large quantities (in some cases exceeding 25 ml; kerosene costs 0.25 USD/ litre) of kerosene, the technology usage manual was revised and it recommended usage of 10- 20 gm of twigs during lighting the stove along with pellets which generated enough heat for pellets to reach ignition temperature. 4.3.3 Reflexive action: Laak, Raven and Verbong (2007) define reflexive action in transition literature as attention/inclination to question “underlying assumptions such as social values”, and the willingness to change course if the technology does not match these assumptions. Under the project, no such reflexive action was demonstrated. It may be concluded that while there is evidence of first-order learning, defined by Raven (2005) as learning about the effectiveness of a certain technology to achieve a specific goal, there is significant scope of improvement in terms of ‘second order learning’ of reflexive action . 4.4 Protection from regime: As Caniels and Romijn (2008) points out that the rationale of protection is to create a space for experimenting with and executing the innovation process without being subject to immediate market pressures, this experimental project was protected in multiple direct and indirect ways. 4.4.1 Supply side: The project offered direct protection to ensure regular supply of pellets both for user trials and off the shelf stock in an environment without any immediate and direct market demand which are described below: 22.214.171.124 Capital cost subsidy: As it was a government sponsored project, local entrepreneur did not have to pay the capital cost of the pellet machine or initial establishment cost like power connectivity cost and hence has the liberty of conducting variety of resource intensive experiments to develop quality pellets instead of focusing of achieving “break even”. Further, this enable reduction of pellet cost to not only to maintain the price ceiling but also to make profit of about 120 USD/tonne. As Raven (2005) pointed out, such protected space created on the basis of expectations (by the sponsor) enabled technologists to focus on development of a radical technology which had no “contemporary” market value thereby providing “temporary” exemption from dominant regime rules. 126.96.36.199 Technical handholding: Technical and marketing experts from TERI were engaged in hand holding of the entrepreneur and his team across the entire value chain- from machine selection to home delivery of pellets. It helped build local capacity to carry out pelletization as a professional commercial enterprise. 4.4.2 Demand side: TERI also executed other activities in the same area which helped indirectly in creating demand for pellets which are described below: 188.8.131.52 Awareness about benefits related to clean cooking: Extensive awareness generation campaigns under the project were carried out to sensitize local community about benefits of clean cooking which otherwise would be significantly expensive for pellet entrepreneur. 184.108.40.206 Dissemination of forced draft stoves: Forced draft cook stoves with top-loading system (which require small size wood pieces) were disseminated to almost 1000 households in that area under other project activities. These beneficiaries faced a manually tedious job of chopping wood and hence households who were then already purchasing wood expressed interest to purchase small sized pellets which will save the hard work at no extra price. Such unique local conditions helped in development of a technological niche for the “radical innovation” of pellets which helped users to create/learn about a new need-pellets and the technology provider to receive user feedback leading to improvement of quality and reduction of cost (Raven, 2005; Mourik and Raven, 2006). Lessons drawn from this experiemental project can help create a market in the long run where a technologically capable entrepreneur can supply pellets in a commercially sustainable manner thereby replacing the dominant regime of biomass under-utilization and usage of wood as cooking fuel. 5.0 Conclusion: Like any other “radical innovation”, pelletization would require a long process (even more than a decade) of mutual adjustment and adaptation to form a part of the then dominant regime of household energy consumption behavior (van Eijck and Romijn, 2008). As Raven (2005) also pointed out niches are “at the cosmopolitan level of- and above- the local practices” of experimental projects, there is need to investigate the barriers to horizontal scaling of the “experimental project” to a scale which is “beyond the local level” to be categorized as a “niche” (Mourik and Raven, 2006). SNM can significantly contribute to this process by managing the interaction between the different local projects, and by managing the interaction between these local projects and the wider selection environment -regime and landscape (Mourik and Raven, 2006). As single experiments do not result in regime change (Raven, 2005), it is necessary to involve more actors for further research in pelletization technology and implementation of multiple pelletization projects across various agro-climatic and socio-economic zones to enable comparison between local practices and development of generic lessons. As Raven, Bosch, and Weterings (2007) suggest, it is also critical to engage in ‘aggregation activities’ like technology standardization, documentation and dissemination of best practices to “gradually add up to a new technology trajectory” which is envisaged to result in sustainable transition in the long run. References: 1. Arcenas, A., Bojob J., Larsenc B., Nunezed F.R., 2010.The Economic Costs of Indoor Air Pollution: New Results for Indonesia, the Philippines, and TimorLeste. Journal of Natural Resources Policy Research, 2(1), 75–93. 2. Atkins A., Bignal K.L., Zhou J.L., Cazier F., 2010. Profiles of polycyclic aromatic hydrocarbons and polychlorinated biphenyls from the combustion of biomass pellets, Chemosphere, 78: 1385-92 3. Bergman, P.C.A., 2005. Combined torrefaction and pelletisation. The TOP process. 4. Berkhout, F., Verbong, G., Wieczorek, A., Raven, R., Lebel, L., Bai, X., 2010. Sustainability experiments in Asia: innovations shaping alternative development pathways? Environmental Science and Policy, 13: 261–271. 5. Berkhout, F., Verbong, G.P.J., Wieczorek, A.J., Raven, R.P.J.M., Lebel, L., Bai, X., 2010. Sustainability experiments in Asia: niches inﬂuencing alternative development pathways? Environmental Science and Policy 13, 261–271. 6. Caniëls, M and Romijn, H., 2008. Actor networks in Strategic Niche Management: Insights from Social Network Theory. Futures, 40 (7): 613-629. 7. Chin O.C., Siddiqui K.M., 2000. Characteristics of some biomass briquettes prepared under modest die pressures, Biomass and Bioenergy 18, 223-228 8. Desai M.A., Mehta S., Smith K.R., 2004. Indoor smoke from solid fuels: assessing the environmental burden of disease at national and local levels. WHO Environmental Burden of Disease Series, No. 4, Geneva. 9. Hoogma, R., 2000. Exploiting technological niches: Strategies for experimental introduction of electric vehicles, Thesis, Twente University, Enschede 10. Kemp, R., Schot, J.W., Hoogma, R., 1998. Regime shifts to sustainability through processes of niche formation: the approach of strategic niche management. Technology Analysis and Strategic Management (10): 175–195. 11. Lehtikangas P., 2000. Storage effects on pelletised sawdust, logging residues and bark. Biomass and Bioenergy, 19: 287-293. 12. Loo S.V., Koppejan J., 2008. The Handbook of Biomass Combustion and Co-firing, Earthscan, London 13. Mourik R., Raven R., 2006. A practioner’s view on Strategic Niche Management., Eindhoven University of Technology, The Netherlands. 14. Parashar, D.C Gadi R., Mandal, T.K., Mitra, A.P., 2005. Carbonaceous aerosol emissions from India. Atmospheric Environment 39: 7861–7871 15. Raven, R.P.J.M., 2005. Strategic niche management for biomass. Ph.D. Thesis. Eindhoven University of Technology, The Netherlands. 16. Raven, R.P.J.M., Bosch, S. van den, Weterings, R., 2007. Transitions and strategic niche management : towards a competence kit for practitioners. In: Proceedings of the 4th Dubrovnic Conference on Sustainable Development of Energy, Water and Environment Systems, 4-8 June 2007, Dubrovnic, Croatia. 17. Ravindranath N.H., Balachandra P., 2009. Sustainable Bioenergy for India: Technical, economic and policy analysis. Energy (34): 1003–1013. 18. Rehfuess E., Mehta S.,2006. Prüss-ÜstunA. Assessing household solid fuel use: multiple implications for the millennium development goals. Environment Health Perspective, 3: 373–87 19. Rehman I.H., Kar A., Raven R., Singh D., Tiwari J., Jha R., Sinha P. K., Mirza A., 2010. Rural energy transitions in developing countries: a case of the Uttam Urja initiative in India. Environmental Science and Policy (13): 301-311. 20. Romijn H., Raven R., Visser I., (2010). Biomass energy experiments in rural India: Insights from learning-based development approaches and lessons for Strategic Niche Management. Environmental Science and Policy (13): 326-338 21. S. Mani. 2005. A systems analysis of biomass densification process. Ph.D. Thesis. Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, Canada. 22. Saxena, N.C., 1997. The Woodfuel Scenario and Policy Issues in India, Field Document No. 49, Regional Wood Energy Development Programme in Asia, GCP/RAS/154/NET, pp. 1-72 23. Sharma M., Mukunda H.S., Sridhar G., 2009. Solid fuel block as an alternate fuel for cooking and barbecuing: Preliminary results. Energy Conversion and Management (50): 955-961 24. Smith K.R, Ezzati M., 2005. How Environmental Health Risks Change With Development: The Epidemiologic and Environmental Risk Transitions Revisited. Annual Review of Environment and Resources 30, 291–333 25. Sokhansanj S., Fenton J., 2006. Cost benefit of biomass supply and pre-processing. A BIOCAP Research Integration Program Synthesis Paper. 26. van Eijck, J. and Romijn, H., 2008. Prospects for Jatropha biofuels in developing countries: An analysis for Tanzania with Strategic Niche Management. Energy Policy, 36 (1): 311-32 27. Venkataraman C., Sagar A.D., Habib G., Lam N., Smith K.R., 2010. The Indian National Initiative for Advanced Biomass Cookstoves: The benefits of clean combustion. Energy for sustainable development (14):63-72 28. Witkamp M. J., Raven R.P.J.M., Royakkers L.M.M., 2010, Strategic Niche Management of Social Innovation: the case of Social Entrepreneurship in the Netherlands, Eindhoven Centre for Innovation Studies, Netherlands 29. World Energy Outlook 2007, International Energy Agency (IEA), Geneva 30. Yang Y.B., Ryu C., Khor A., Sharifi V N., Swithenbank J., 2005, Fuel size effect on pinewood combustion in a packed bed, Fuel, 84: 2026-2038.