270 research outputs found
Solar hydrogen system for cooking applications: Experimental and numerical study
This paper describes the development of a semi-empirical numerical model for a solar hydrogen system consisting of a proton exchange membrane electrolyser (PEM) powered by photovoltaic panels to produce hydrogen as fuel for cooking applications, focussing on Jamaica as a suitable case-study. The model was developed in TRNSYS and includes a novel numerical component based on FORTRAN to model the operation of the PEM electrolyser. The numerical component was developed based on operational data from a purpose constructed small-scale experimental rig. The numerical model was calibrated using data from the experimental rig powered by operational data from a photovoltaic panel system in the UK and predicted photovoltaic panel power data from Jamaica. For the test conditions, experiments indicated an electrolysis maximum efficiency of 63.6%. The calibrated model was used to develop a case study analysis for a small community in Jamaica with a daily cooking demand of 39.6kWh or 1.7kg of H2 gas. Simulations indicate that the H2 production plan is sufficient for the cooking needs of the case-study.This project is partly funded by ACP Caribbean & Pacific Research Programme for Sustainable Development of the European Union (EuropeAid/130381/D/ACT/ACP)
Governing effective and legitimate smart grid developments
Smart grids which use Information and Communication Technologies to augment energy network management have been developed in several locations including London and Stockholm. Common rationales for smart grids include: de-carbonising energy supply, maintaining security of supply and promoting affordability. However, beyond these general abstractions, smart grids seem to exhibit considerable diversity in terms of their characteristics and rationales for development. Thus, while the term smart grid may imply abstract notions of what smart grids are and might do, they are developed in response to local contingencies and diverse. In this paper we therefore explore the governance processes through which smart grids are constructed. The paper suggests that standardising smart grids through definitions and best practices that fix both problems and solutions should be avoided. Rather governance processes should be promoted in which local contingencies can be articulated and more legitimate smart grids developed in response to these
Mapping land use changes resulting from biofuel production and the effect of mitigation measures
Many of the sustainability concerns of bioenergy are related to direct or indirect land use change (LUC) resulting from bioenergy feedstock production. The environmental and socio-economic impacts of LUC highly depend on the site-specific biophysical and socio-economic conditions. The objective of this study is to spatiotemporally assess the potential LUC dynamics resulting from an increased biofuel demand, the related greenhouse gas (GHG) emissions, and the potential effect of LUC mitigation measures. This assessment is demonstrated for LUC dynamics in Brazil towards 2030, considering an increase in the global demand for bioethanol as well as other agricultural commodities. The potential effects of three LUC mitigation measures (increased agricultural productivity, shift to second-generation ethanol, and strict conservation policies) are evaluated by using a scenario approach. The novel modelling framework developed consists of the global Computable General Equilibrium model MAGNET, the spatiotemporal land use allocation model PLUC, and a GIS-based carbon module. The modelling simulations illustrate where LUC as a result of an increased global ethanol demand (+26x10(9)L ethanol production in Brazil) is likely to occur. When no measures are taken, sugar cane production is projected to expand mostly at the expense of agricultural land which subsequently leads to the loss of natural vegetation (natural forest and grass and shrubland) in the Cerrado and Amazon. The related losses of above and below ground biomass and soil organic carbon result in the average emission of 26gCO(2-)eq/MJbioethanol. All LUC mitigation measures show potential to reduce the loss of natural vegetation (18%-96%) as well as the LUC-related GHG emissions (7%-60%). Although there are several uncertainties regarding the exact location and magnitude of LUC and related GHG emissions, this study shows that the implementation of LUC mitigation measures could have a substantial contribution to the reduction of LUC-related emissions of bioethanol. However, an integrated approach targeting all land uses is required to obtain substantial and sustained LUC-related GHG emission reductions in general
Substitute or complement? Assessing renewable and nonrenewable energy in OECD countries
The elasticity of interfuel substitution between renewable and nonrenewable energy is key to establishing effective climate change policy. This is the first study to estimate the elasticity of substitution between different fossil fuels and renewable resources. We used 12 manufacturing industry-level datasets for the OECD countries from 1995 to 2009. We found a complementary relationship from nonrenewable energy to renewable energy in eight industries, whereas a substitute relationship was maintained for four industries. In particular, the food and pulp industries had a strong complementary relationship
Environmental and resource burdens associated with world biofuel production out to 2050:footprint components from carbon emissions and land use to waste arisings and water consumption
Environmental or ‘ecological’ footprints have been widely used in recent years as indicators of resource consumption and waste absorption presented in terms of biologically productive land area [in global hectares (gha)] required per capita with prevailing technology. In contrast, ‘carbon footprints’ are the amount of carbon (or carbon dioxide equivalent) emissions for such activities in units of mass or weight (like kilograms per functional unit), but can be translated into a component of the environmental footprint (on a gha basis). The carbon and environmental footprints associated with the world production of liquid biofuels have been computed for the period 2010–2050. Estimates of future global biofuel production were adopted from the 2011 International Energy Agency (IEA) ‘technology roadmap’ for transport biofuels. This suggests that, although first generation biofuels will dominate the market up to 2020, advanced or second generation biofuels might constitute some 75% of biofuel production by 2050. The overall environmental footprint was estimated to be 0.29 billion (bn) gha in 2010 and is likely to grow to around 2.57 bn gha by 2050. It was then disaggregated into various components: bioproductive land, built land, carbon emissions, embodied energy, materials and waste, transport, and water consumption. This component‐based approach has enabled the examination of the Manufactured and Natural Capital elements of the ‘four capitals’ model of sustainability quite broadly, along with specific issues (such as the linkages associated with the so‐called energy–land–water nexus). Bioproductive land use was found to exhibit the largest footprint component (a 48% share in 2050), followed by the carbon footprint (23%), embodied energy (16%), and then the water footprint (9%). Footprint components related to built land, transport and waste arisings were all found to account for an insignificant proportion to the overall environmental footprint, together amounting to only about 2
Perceived barriers and policy solutions in clean energy infrastructure investment
International political negotiations and national policy for climate change mitigation are increasingly focussed on the mobilisation and scale up of investments in clean energy infrastructure. This paper aims to develop the understanding of how institutional investors in the private sector perceive barriers to scaling up investment into clean energy infrastructure and what policy solutions to those barriers they advocate. This paper adds to existing scientific knowledge through a clear focus on private sector perceptions. Through the analysis of previous public statements from organisations and coalitions in the finance sector a number of investment barriers were identified. These initial barriers fed into a Delphi process. The outputs of the Delphi process were categorized into five sets of barriers and a number of policy solutions associated with investing into clean energy solutions. We conclude that there is a need for better engagement with the institutional investment community to ensure further effort on policy development that underpins investments at scale is effective and efficient
Air conditioning and electricity expenditure: The role of climate in temperate countries
This paper investigates how households adopt and use air conditioning to adapt to climate change and increasingly high temperatures, which pose a threat to the health of vulnerable populations. The analysis examines conditions in eight temperate, industrialized countries (Australia, Canada, France, Japan, the Netherlands, Spain, Sweden, and Switzerland). The identification strategy exploits cross-country and cross-household variations by matching geocoded households with climate data. Our findings suggest that households respond to excess heat by purchasing and using air conditioners, leading to increased electricity consumption. Households on average spend 35%–42% more on electricity when they adopt air conditioning. Through an illustrative analysis, we show that climate change and the growing demand for air conditioning are likely to exacerbate energy poverty. The number of energy poor who spend a high share of income on electricity increases, and households in the lowest income quantile are the most negatively affected
Cities and climate change mitigation: Economic opportunities and governance challenges in Asia
Cities are central to the fight against climate change, but the IPCC recently noted that many cities — and particularly those in the developing world — lack the institutional, financial and technical capacities needed to switch to low emission development paths. Based on detailed case studies of three Asian cities, this paper finds that the adoption of low emission development strategies (LEDS) at the urban level could be economically attractive. However, it also argues that without a coordinated multi-level, cross-sectoral governance framework these opportunities for low carbon urban development are likely to be left unexploited. As these governance conditions are frequently not in place, we argue that these case study cities, and cities in similar contexts, are likely to miss even the economically attractive low carbon development opportunities and become increasingly locked in to higher cost, higher carbon development paths. Due to their growing size and importance, we conclude that the presence or absence of governance arrangements that enable the adoption of low carbon development strategies in Asian cities will have global implications for climate change
Energy Metabolism of 28 World Countries: A Multi-scale Integrated Analysis
In this paper the Multi-Scale Integrated Analysis of Social Metabolism (MuSIASEM) is used to investigate the metabolic profile of 28 world countries. The years considered are 1995 and 2007 and the socio-economic and environmental data included in the World Input-Output Database (WIOD) are used to provide consistent comparisons between countries. The analyses are performed by considering the entire society (Level N), the household and the paid sectors (Level N-1) and the different economic sectors (Level N-2). The main results show that, despite the differences existing between countries, the increasing energy throughput and per-capita consumption contributed to change the metabolic profile of the countries considered in this paper
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