895 resultados para Renewable energy resources


Relevância:

100.00% 100.00%

Publicador:

Resumo:

This talk explores a new opportunity renewable energy technology has for society.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The paper presents a demand side response scheme,which assists electricity consumers to proactively control own demands in such a way to deliberately avert congestion periods on the electrical network. The scheme allows shifting loads from peak to low demand periods in an attempt to flattening the national electricity requirement. The scheme can be concurrently used to accommodate the utilization of renewable energy sources,that might be available at user’s premises. In addition the scheme allows a full-capacity utilization of the available electrical infrastructure by organizing a wide-use of electric vehicles. The scheme is applicable in the Eastern and Southern States of Australia managed by the Australian Energy Market Operator. The results indicate the potential of the scheme to achieve energy savings and release capacity to accommodate renewable energy and electrical vehicle technologies.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The conversion of tamarind seeds into pyrolytic oil by fixed bed fire-tube heating reactor has been taken into consideration in this study. The major components of the system were fixed bed fire-tube heating reactor, liquid condenser and collectors. The raw and crushed tamarind seed in particle form was pyrolized in an electrically heated 10 cm diameter and 27 cm high fixed bed reactor. The products are oil, char and gases. The parameters varied were reactor bed temperature, running time, gas flow rate and feed particle size. The parameters were found to influence the product yields significantly. The maximum liquid yield was 45 wt% at 4000C for a feed size of 1.07cm3 at a gas flow rate of 6 liter/min with a running time of 30 minute. The pyrolysis oil was obtained at these optimum process conditions were analyzed for physical and chemical properties to be used as an alternative fuel.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

To minimise the number of load sheddings in a microgrid (MG) during autonomous operation, islanded neighbour MGs can be interconnected if they are on a self-healing network and an extra generation capacity is available in the distributed energy resources (DER) of one of the MGs. In this way, the total load in the system of interconnected MGs can be shared by all the DERs within those MGs. However, for this purpose, carefully designed self-healing and supply restoration control algorithm, protection systems and communication infrastructure are required at the network and MG levels. In this study, first, a hierarchical control structure is discussed for interconnecting the neighbour autonomous MGs where the introduced primary control level is the main focus of this study. Through the developed primary control level, this study demonstrates how the parallel DERs in the system of multiple interconnected autonomous MGs can properly share the load of the system. This controller is designed such that the converter-interfaced DERs operate in a voltage-controlled mode following a decentralised power sharing algorithm based on droop control. DER converters are controlled based on a per-phase technique instead of a conventional direct-quadratic transformation technique. In addition, linear quadratic regulator-based state feedback controllers, which are more stable than conventional proportional integrator controllers, are utilised to prevent instability and weak dynamic performances of the DERs when autonomous MGs are interconnected. The efficacy of the primary control level of the DERs in the system of multiple interconnected autonomous MGs is validated through the PSCAD/EMTDC simulations considering detailed dynamic models of DERs and converters.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper describes a diode-clamped three-level inverter-based battery/supercapacitor direct integration scheme for renewable energy systems. The study is carried out for three different cases. In the first case, one of the two dc-link capacitors of the inverter is replaced by a battery bank and the other by a supercapacitor bank. In the second case, dc-link capacitors are replaced by two battery banks. In the third case, ordinary dc-link capacitors are replaced by two supercapacitor banks. The first system is supposed to mitigate both long-term and short-term power fluctuations while the last two systems are intended for smoothening long-term and short-term power fluctuations, respectively. These topologies eliminate the need for interfacing dc-dc converters and thus considerably improve the overall system efficiency. The major issue in aforementioned systems is the unavoidable imbalance in dc-link voltages. An analysis on the effects of unbalance and a space vector modulation method, which can produce undistorted current even in the presence of such unbalances, are presented in this paper. Furthermore, small vector selection-based power sharing and state of charge balancing techniques are proposed. Experimental results, obtained from a laboratory prototype, are presented to verify the efficacy of the proposed modulation and control techniques.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper presents a novel battery direct integration scheme for renewable energy systems. The idea is to replace ordinary capacitors of a three-level flying-capacitor inverter by three battery banks to alleviate power fluctuations in renewable generation. This approach eliminates the need for interfacing dc-dc converters and thus considerably improves the overall efficiency. However, the major problem with this approach is the uneven distribution of space vectors which is due to unavoidable unbalance in clamping voltages. A detailed analysis on the effects of this issue and a novel carrier based pulse width modulation method, which can generate undistorted currents even in the presence of unevenly distributed space vectors, are presented in this paper. A charge/discharge controller is also proposed for power sharing and state of charge balancing of battery banks. Simulation results are presented to verify the efficacy of the proposed system, modulation method and power sharing controller.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This was a comparative study of the possibility of a net zero energy house in Queensland, Australia. It examines the actual energy use and thermal comfort conditions of an occupied Brisbane home and compares performance with the 10 star scale rating scheme for Australian residential buildings. An adaptive comfort psychometric chart was developed for this analysis. The house's capacity for the use of the natural ventilation was studied by CFD modelling. This study showed that the house succeeded in achieving the definition of net zero energy on an annual and monthly basis for lighting, cooking and space heating / cooling and for 70% of days for lighting, hot water and cooking services.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper critically examines research on consumer attitudes and behavior towards solar photovoltaic (PV) and renewable energy technology in Australia. The uptake of renewable energy technology by residential consumers in Australia in the past decade has transformed the electricity supply and demand paradigm. Thus, this paper reviews Australian research on consumer behavior, understanding and choices in order to identify gaps in knowledge. As the role of the consumer transforms there is a critical need to understand the ways consumers may respond to future energy policies to mitigate unforeseen negative social and economic consequence of programs designed to achieve positive environmental outcomes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Biofuel produced by fast pyrolysis from biomass is a promising candidate. The heart of the system is a reactor which is directly or indirectly heated to approximately 500°C by exhaust gases from a combustor that burns pyrolysis gas and some of the by-product char. In most of the cases, external biomass heater is used as heating source of the system while internal electrical heating is recently implemented as source of reactor heating. However, this heating system causes biomass or other conventional forms of fuel consumption to produce renewable energy and contributes to environmental pollution. In order to overcome these, the feasibility of incorporating solar energy with fast pyrolysis has been investigated. The main advantages of solar reactor heating include renewable source of energy, comparatively simpler devices, and no environmental pollution. A lab scale pyrolysis setup has been examined along with 1.2 m diameter parabolic reflector concentrator that provides hot exhaust gas up to 162°C. The study shows that about 32.4% carbon dioxide (CO2) emissions and almost one-third portion of fuel cost are reduced by incorporating solar heating system. Successful implementation of this proposed solar assisted pyrolysis would open a prospective window of renewable energy.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this thesis various schemes using custom power devices for power quality improvement in low voltage distribution network are studied. Customer operated distributed generators makes a typical network non-radial and affect the power quality. A scheme considering different algorithm of DSTATCOM is proposed for power circulation and islanded operation of the system. To compensate reactive power overflow and facilitate unity power factor, a UPQC is introduced. Stochastic analysis is carried out for different scenarios to get a comprehensive idea about a real life distribution network. Combined operation of static compensator and voltage regulator is tested for the optimum quality and stability of the system.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Integrating renewable energy into public space is becoming more common as a climate change solution. However, this approach is often guided by the environmental pillar of sustainability, with less focus on the economic and social pillars. The purpose of this paper is to examine this issue in the speculative renewable energy propositions for Freshkills Park in New York City submitted for the 2012 Land Art Generator Initiative (LAGI) competition. This paper first proposes an optimal electricity distribution (OED) framework in and around public spaces based on relevant ecology and energy theory (Odum’s fourth and fifth law of thermodynamics). This framework addresses social engagement related to public interaction, and economic engagement related to the estimated quantity of electricity produced, in conjunction with environmental engagement related to the embodied energy required to construct the renewable energy infrastructure. Next, the study uses the OED framework to analyse the top twenty-five projects submitted for the LAGI 2012 competition. The findings reveal an electricity distribution imbalance and suggest a lack of in-depth understanding about sustainable electricity distribution within public space design. The paper concludes with suggestions for future research.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

As cities are rapidly developing new interventions against climate change, embedding renewable energy in public spaces is an important strategy. However, most interventions primarily include environmental sustainability while neglecting the social and economic interrelationships of electricity production. Although there is a growing interest in sustainability within environmental design and landscape architecture, public spaces are still awaiting viable energy-conscious design and assessment interventions. The purpose of this paper is to investigate this issue in a renowned public space—Ballast Point Park in Sydney—using a triple bottom line (TBL) case study approach. The emerging factors and relationships of each component of TBL, within the context of public open space, are identified and discussed. With specific focus on renewable energy distribution in and around Ballast Point Park, the paper concludes with a general design framework, which conceptualizes an optimal distribution of onsite electricity produced from renewable sources embedded in public open spaces.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The development of Electric Energy Storage (EES) integrated with Renewable Energy Resources (RER) has increased use of optimum scheduling strategy in distribution systems. Optimum scheduling of EES can reduce cost of purchased energy by retailers while improve the reliability of customers in distribution system. This paper proposes an optimum scheduling strategy for EES and the evaluation of its impact on reliability of distribution system. Case study shows the impact of the proposed strategy on reliability indices of a distribution system.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Renewable energy is commonly considered a technological addition to urban environments. By contrast, this PhD used a holistic approach to develop a design framework for integrating local electricity production into the ecological function and cultural use of public space. The framework addresses social engagement related to public interaction, and economic engagement related to the estimated quantity of electricity produced, in conjunction with environmental engagement related to the embodied energy required to construct the renewable energy infrastructure. The outcomes will contribute to social and environmental change by engaging society, enriching the local economy and increasing social networks.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This thesis examines the law and policy concerning renewable energy electricity generation in Palestine, Jordan, and Abu Dhabi. The thesis gives greater attention to the promotion of solar power owing to the abundance and viability. It appears that energy security profoundly underpins the utilisation of renewable electricity, and the motivation of climate change mitigation also pays a role in the promotion of renewable energy in these jurisdictions. However, current policies and regulations are not fully able to promote the renewables in the power sector. The thesis submits that reforms of law and policy are necessary to enhance the achievement of environmental and energy goals.