A Hard Bargain? A cost-benefit analysis of an improved cookstove program in India

In developing countries, access to modern energy for cooking and heating still remains a challenge to raising households out of poverty. About 2.5 billion people depend on solid fuels such as biomass, wood, charcoal and animal dung. The use of solid fuels has negative outcomes for health, the environment and economic development (Universal Energy Access, UNDP). In low income countries, 1.3 million deaths occur due to indoor smoke or air pollution from burning solid fuels in small, confined and unventilated kitchens or homes. In addition, pollutants such as black carbon, methane and ozone, emitted when burning inefficient fuels, are responsible for a fraction of the climate change and air pollution. There are international efforts to promote the use of clean cookstoves in developing countries but limited evidence on the economic benefits of such distribution programs. This study undertook a systematic economic evaluation of a program that distributed subsidized improved cookstoves to rural households in India. The evaluation examined the effect of different levels of subsidies on the net benefits to the household and to society. This paper answers the question, ���Ex post, what are the economic benefits to various stakeholders of a program that distributed subsidized improved cookstoves?��� In addressing this question, the evaluation used empirical data from India applied to a cost-benefit model to examine how subsidies affect the costs and the benefits of the biomass improved cookstove and the electric improved cookstove to different stakeholders.

Bridging the Scale Gap from Leaf to Canopy in Biosphere-Atmosphere Gas and Particle Exchanges

<p>Terrestrial ecosystems, occupying more than 25% of the Earth's surface, can serve as</p><p>`biological valves' in regulating the anthropogenic emissions of atmospheric aerosol</p><p>particles and greenhouse gases (GHGs) as responses to their surrounding environments.</p><p>While the signicance of quantifying the exchange rates of GHGs and atmospheric</p><p>aerosol particles between the terrestrial biosphere and the atmosphere is</p><p>hardly questioned in many scientic elds, the progress in improving model predictability,</p><p>data interpretation or the combination of the two remains impeded by</p><p>the lack of precise framework elucidating their dynamic transport processes over a</p><p>wide range of spatiotemporal scales. The diculty in developing prognostic modeling</p><p>tools to quantify the source or sink strength of these atmospheric substances</p><p>can be further magnied by the fact that the climate system is also sensitive to the</p><p>feedback from terrestrial ecosystems forming the so-called `feedback cycle'. Hence,</p><p>the emergent need is to reduce uncertainties when assessing this complex and dynamic</p><p>feedback cycle that is necessary to support the decisions of mitigation and</p><p>adaptation policies associated with human activities (e.g., anthropogenic emission</p><p>controls and land use managements) under current and future climate regimes.</p><p>With the goal to improve the predictions for the biosphere-atmosphere exchange</p><p>of biologically active gases and atmospheric aerosol particles, the main focus of this</p><p>dissertation is on revising and up-scaling the biotic and abiotic transport processes</p><p>from leaf to canopy scales. The validity of previous modeling studies in determining</p><p>iv</p><p>the exchange rate of gases and particles is evaluated with detailed descriptions of their</p><p>limitations. Mechanistic-based modeling approaches along with empirical studies</p><p>across dierent scales are employed to rene the mathematical descriptions of surface</p><p>conductance responsible for gas and particle exchanges as commonly adopted by all</p><p>operational models. Specically, how variation in horizontal leaf area density within</p><p>the vegetated medium, leaf size and leaf microroughness impact the aerodynamic attributes</p><p>and thereby the ultrane particle collection eciency at the leaf/branch scale</p><p>is explored using wind tunnel experiments with interpretations by a porous media</p><p>model and a scaling analysis. A multi-layered and size-resolved second-order closure</p><p>model combined with particle </p><p>uxes and concentration measurements within and</p><p>above a forest is used to explore the particle transport processes within the canopy</p><p>sub-layer and the partitioning of particle deposition onto canopy medium and forest</p><p>oor. For gases, a modeling framework accounting for the leaf-level boundary layer</p><p>eects on the stomatal pathway for gas exchange is proposed and combined with sap</p><p>ux measurements in a wind tunnel to assess how leaf-level transpiration varies with</p><p>increasing wind speed. How exogenous environmental conditions and endogenous</p><p>soil-root-stem-leaf hydraulic and eco-physiological properties impact the above- and</p><p>below-ground water dynamics in the soil-plant system and shape plant responses</p><p>to droughts is assessed by a porous media model that accommodates the transient</p><p>water </p><p>ow within the plant vascular system and is coupled with the aforementioned</p><p>leaf-level gas exchange model and soil-root interaction model. It should be noted</p><p>that tackling all aspects of potential issues causing uncertainties in forecasting the</p><p>feedback cycle between terrestrial ecosystem and the climate is unrealistic in a single</p><p>dissertation but further research questions and opportunities based on the foundation</p><p>derived from this dissertation are also brie</p><p>y discussed.</p>