7,196,333 research outputs found

    Energy

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    Energy

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    Resource /Energy Economics and Policy,

    A grassroots sustainable energy niche? Reflections on community energy case studies

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    System changing innovations for sustainability transitions are proposed to emerge in radical innovative niches. ‘Strategic Niche Management’ theory predicts that niche level actors and networks will aggregate learning from local projects, distilling and disseminating best practice. This should lower the bar for new projects to form and establish, thereby encouraging the innovation to diffuse through replication. Within this literature, grassroots innovations emerging from civil society are an under researched site of sociotechnical innovation for sustainable energy transitions. We consider the emerging community energy sector in the UK, in order to empirically test this model. Community energy is a diverse grassroots led sector including both demand and supply side initiatives for sustainable energy such as community owned renewable energy generation, village hall refurbishments, behaviour change initiatives and energy efficiency projects. Our analysis draws on in depth qualitative case study research with twelve local projects, and a study of how intermediary organisations aim to support local projects and encourage replication. This rich data allows us to examine the extent and nature of interactions between projects and intermediary actors in order to evaluate the utility of niche theories in the civil society context. In particular, we investigate which types of knowledge, support and resources were needed by our case study projects to become established and thrive, and compare and contrast this with those offered by the emerging community energy niche. Our findings indicate that while networking and intermediary organisations can effectively collate and spread some types of learning and information necessary for replication, this is not sufficient: tacit knowledge, trust and confidence are essential to these projects’ success, but are more difficult to abstract and translate to new settings. We draw out the implications of our findings for niche theory, for community energy and other grassroots practitioners aiming to build robust influential niches, and for policymakers eager to harness civil society’s innovative potential for sustainability

    Hybrid energy converter based on swirling combustion chambers: the hydrocarbon feeding analysis

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    This manuscript reports the latest investigations about a miniaturized hybrid energy power source, compatible with thermal/electrical conversion, by a thermo-photovoltaic cell, and potentially useful for civil and space applications. The converter is a thermally-conductive emitting parallelepiped element and the basic idea is to heat up its emitting surfaces by means of combustion, occurred in swirling chambers, integrated inside the device, and/or by the sun, which may work simultaneously or alternatively to the combustion. The current upgrades consist in examining whether the device might fulfill specific design constraints, adopting hydrocarbons-feeding. Previous papers, published by the author, demonstrate the hydrogen-feeding effectiveness. The project's constraints are: 1) emitting surface dimensions fixed to 30 × 30 mm, 2) surface peak temperature T > 1000 K and the relative ΔT < 100 K (during the combustion mode), 3) the highest possible delivered power to the ambient, and 4) thermal efficiency greater than 20% when works with solar energy. To this end, a 5 connected swirling chambers configuration (3 mm of diameter), with 500 W of injected chemical power, stoichiometric conditions and detailed chemistry, has been adopted. Reactive numerical simulations show that the stiff methane chemical structure obliges to increase the operating pressure, up to 10 atm, and to add hydrogen, to the methane fuel injection, in order to obtain stable combustion and efficient energy conversion

    A virtual power plant model for time-driven power flow calculations

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    This paper presents the implementation of a custom-made virtual power plant model in OpenDSS. The goal is to develop a model adequate for time-driven power flow calculations in distribution systems. The virtual power plant is modeled as the aggregation of renewable generation and energy storage connected to the distribution system through an inverter. The implemented operation mode allows the virtual power plant to act as a single dispatchable generation unit. The case studies presented in the paper demonstrate that the model behaves according to the specified control algorithm and show how it can be incorporated into the solution scheme of a general parallel genetic algorithm in order to obtain the optimal day-ahead dispatch. Simulation results exhibit a clear benefit from the deployment of a virtual power plant when compared to distributed generation based only on renewable intermittent generation.Peer ReviewedPostprint (published version

    Product longevity and shared ownership: Sustainable routes to satisfying the world’s growing demand for goods&nbsp;

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    It has been estimated that by 2030 the number of people who are wealthy enough to be significant consumers will have tripled. This will have a dramatic impact on the demands for primary materials and energy. It has been estimated that with improvements in design and manufacturing it is possible to maintain the current level of production using 70% of the current primary material consumed. Even with these improvements on the production side, there will still be a doubling of primary material requirements by the end of the century, with accompanying rises in industrial energy demand, if the rise in demand for goods and services is to be met. It is therefore clear that the consumption of products must also be explored. Product longevity and using goods more intensively are two strategies which could reduce the demand for new goods. If products last longer, then manufacturing output can concentrate on emerging markets rather than the market for replacement goods. There are many goods which are infrequently used, these seldom wear out. The total demand for such could be drastically reduced if they we re shared with other people. Sharing of goods has traditionally been conducted between friends or by hiring equipment, but modern communication systems and social media could increase the opportunities to share goods. Sharing goods also increases access to a range of goods for those on low incomes. From a series of workshops it has been found that the principal challenges are sociological rather than technological. This paper contains a discussion of these challenges and explores possible futures where these two strategies have been adopted. In addition, the barriers and opportunities that these strategies offer for 548 AIMS Energy Volume 3, Issue 4, 547-561. consumers and businesses are identified, and areas where government policy could be instigated to bring about change are highlighted

    A new NANOSATs propulsion system: swirling-combustion chamber and water electrolysis

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    Defined for academic purposes (low budget projects), NanoSats become of interest in the government and industry communities, since the deployment of swarms would able to act as a single orbiting constellation, providing greater coverage and faster update rates than can be achieved using conventional single satellite operations. On the other hand, that accomplishment is hampered by the absence, due to the satellite’s small dimensions, of an independent efficient propulsion system. This paper investigates the potentialities of a swirling-micropropulsion system that would permit NANOSATs to be “propulsive-independent”. This would allow orbital operations, even at very low altitude, and/or increasing also life-times. The propulsion system, patent pending, adopts H2/O2 obtained by water electrolysis, a swirling combustion chamber and a sub-supersonic nozzle to optimize the thrust. The numerical combustion simulations, of the micro-thrust chamber, show that performances are impressive, in particular if compared to the dimensions, and this would be of benefit in fields such as intelligence, disaster monitoring, CBRNe observation, telecommunications and identification
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