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Abstract This paper describes a preliminary analysis on the integration of renewable energy systems in smart microgrids. The initial theoretical evaluations are referred to the case study of a laboratory DC microgrid interconnecting: electric mobility, stationary storage systems and renewable energy sources in a smart grid scenario. Specific power architectures for the integration of a 7kWp solar generation system with the considered microgrid are analysed and compared, in terms of efficiency and costs, in order to support the choice and the design of optimal solutions. Modeling and simulations of the related components are carried out in Matlab-Simulink environment in order to evaluate the performance of different embedded maximum power point tracking techniques, working in balanced and unbalanced irradiance conditions for the considered PV generation system. The promising results and the considerations reported in this paper highlight the importance of using the proposed smart power architectures and the related control techniques to support the optimal use of sustainable energy generation systems. [ABSTRACT FROM AUTHOR]

The objective of this paper was to show that a combination of renewable energy sources with energy storage systems, which provide frequency containment reserves FCR (also called primary frequency control), improves the performance of both systems. This double benefit comes out in a reduction of intraday trading for the storage system and a leveled power injection of the renewables. Considering the regulations that apply for battery storage systems to provide FCR in Germany, interaction with other units is essential to guarantee availability of the system. This interaction is usually performed market based by intraday trading or by flexible power generation or consumption combined with the storage system. This paper, however, showed the benefits of interaction with fluctuating renewable energy sources. Energy storages and renewables were clustered to a common grid connection point to utilize the fluctuations of the renewable power generation directly for battery management. Simulation results based on sample photovoltaic and wind profiles showed the double benefit of the configuration. Intraday trading was reduced by 33% up to 57%. At the same time, fluctuations decreased, so the renewable power injection better matched a predefined power schedule. [ABSTRACT FROM AUTHOR]

The paper discusses problems of energy supply of buildings using renewable sources given the local climatic conditions. The meteorological conditions in Latvia and Riga for last year were analyzed. In paper shows examples of energy efficient buildings allowing that to provide comfort temperature and indoor air quality. The structure and composition of local building materials, providing good thermal insulation are described. The heating systems for test buildings using renewable energy sources were investigated. The assessment of the energy efficiency of the “air-air” and “air-water” heat pumps is studied. [ABSTRACT FROM AUTHOR]

Abstract: Urban neighborhoods could represent an optimal scale for the implementation of innovative energy strategies. However, barriers at the economic, regulatory and administrative level are still present. In this framework, it is important to operate on three levels of the energy system: by reducing energy demand; by optimizing generation and management system, and by integrating local renewable energy sources. In recent years, as a result of an important agreement with the Italian Ministry of Environment, Lombardy Region has supported numerous measures for energy efficiency and renewable resources integration among its territory. The funding supported different actions such as improvements of the buildings envelope, substitution of old gas boilers for heat generation with more efficient components, integration of solar thermal systems in buildings, hydrogen and more sustainable mobility, and district heating plants, which present contribution concerns. About district heating the incentives were provided within two different calls: one aimed at the creation of plants and district heating networks and another for the extension of existing systems. Main aim of the research is to evaluate effects, effectiveness, pros and cons of the several calls for funding; to that end a methodology was developed in order to collect the data and elaborate representative energy, environmental and economic indicators. The most important characteristics, conditions and technical features of the considered plants are described in the present paper trying to provide information on the effectiveness of the supporting measures taken in order to orient future choices and to identify the most promising strategies and technologies for improving energy and environmental performances of communities. In particular present paper is related to 10 district heating plants: 6 are based on biomass and located in mountain areas, 3 are based on natural gas and located in urban areas, while the last is connected to the urban waste to energy plant. One of the important lesson is learned is that district heating (fuelled by biomass, fossil, waste and CHP or not) represents an innovative field of knowledge far from standard: in general each plant has to be evaluated on the basis of specify characteristics and it is very hard to find out average performances from the environmental and economic point of view. The results obtained during the monitoring campaign could help in providing information on the effectiveness of the supporting measures adopted and also to orient future choices by Lombardy Region and, in particular, to identify the most promising technologies for improving energy and environmental performances of communities and to develop a model for the optimization of energy use in the built environment. [Copyright &y& Elsevier]

Abstract: Solar PV systems have evolved from small stand-alone applications through residential and commercial systems to MW-scale installations and groups of systems that feed significant energy into the utility grid. High PV penetration levels create a number of challenges for the management of the operation of the utility grid. This paper will cover the current and historic status of the integration of renewable energies into utility grids over a variety of global regions. This includes grid control and network planning. The technology for the integration of PV is described including the codes and standards governing the utility interactivity requirements. This will include short term dynamic responses as well as power ramp rates. Geographic, technological, and meteorological factors will be discussed. The coordination of meteorology and energy production is a key factor that is examined in detail including real world data. The paper includes a discussion of future utility grid features to support increasing levels of PV and other renewable generation sources. [Copyright &y& Elsevier]

Abstract: This paper represented analysis of wind speed and study of vertical axis wind turbine. There are two type vertical axis wind turbine that had been discussed on this paper that are Darrieus type and Savonius type wind turbine. The wind speed data is recorded using Davis Vantage Pro2 Weather station. A few calculations has been done to get output power from the wind to shows the possibilities and potentialities of wind energy whether it can be develop in Perlis. [Copyright &y& Elsevier]

Abstract: Chaos control means to design a controller that is able to eliminating the chaos behaviour of nonlinear systems that experiencing such phenomenon. In this paper, a delayed feedback control mode is presented. The paper describes the control of the bifurcation behaviour of a modular peak current-mode controlled DC-DC boost converter which is used to provide an interface between energy storage batteries and photovoltaic (PV) arrays renewable energy sources. The parallel-input/parallel-output converter comprises two identical boost circuits and operates in the continuous-current conduction mode. A comparison is made between waveforms obtained from a MATLAB/SIMULINK model for open-loop converter and the controlled one. The study shows the effectiveness of the designed delayed feedback control mode. [Copyright &y& Elsevier]

Abstract: Given the blindness in present wind power integration decision-making, the paper constructed complete index system considering the characteristics of the wind power integration. By means of introducing the tolerance matrix into fuzzy AHP, the judgment matrix is easy to test consistency. The paper used the improved fuzzy AHP to make decision on the wind power integration schemes. The calculation results show that the method is practical. [Copyright &y& Elsevier]

Abstract: Renewable energies are growing fast and have occupied great percentage in power generation. However, one major drawback of most renewable energies is the variability due to the stochastic nature of wind speed, solar irradiation, and etc. It is important to integrate the risk of wind power''s uncertainty into profitability assessments for investors. In this paper, certain effective ideas from portfolio theory in financial engineering field are exploited to deal with renewable energies as risky assets to be invested. It''s a systematic way to neutralize risks as well as maximize return values. To adjust these financial tools used to solve renewable energy''s problem, some other financial models and concepts are introduced. Time Series models, ARMA (autoregressive moving average), GARCH (generalized autoregressive conditional heteroscedasticity) and PSO (particle swarm optimization) algorithm are utilized to modify data to be real-time effective. Utility function is introduced to evaluate different energy resources. This paper is abundant with interdisciplinary ideas using advanced risk management methods on renewable energy issues. The proposed approach is also applied in real world problem to provide consulting evidence for power system planning and dispatching in Gansu province, northwest of China. [Copyright &y& Elsevier]

Abstract Energy is of interest for all sectors and all players for different reasons. The emergence of cooperatives in the field of renewables, the need of social and market acceptance of the clean energy resources, the need for stakeholder empowerment towards the implementation of energy projects, the open energy market and the new actors and roles of the so far traditional consumers are some major triggers of increased cooperation of different stakeholders and carriers on energy projects. Under these conditions, the transformation, conversion, and storage of various forms of energy can be served in centralized units called, Energy Ηubs. Energy hubs components can participate in demand response schemes offering flexibility and efficient use of the resources. This paper studies the demand response schemes that have been proposed in the literature and performs a comparison study among them based in certain parameters such as economic operation, reliability, flexibility etc. [ABSTRACT FROM AUTHOR]

Abstract Nowadays, the connections of Renewable Energy Sources to Distribution Networks are increasing in large number. In order to assess the performance of Distribution Network under normal operating conditions Probabilistic Load Flow analysis is necessary in order to take into consideration the stochastic behavior of Load Demands and Renewable Energy Sources (for example the Photovoltaics Generation Units). Generally, Deterministic Load Flow calculations are typically needed to assess the allowed Distributed Generation penetration level for a given network in order to ensure, for example, that Voltage limits are not exceeded. The present paper deals with the Probabilistic Load Flow using Monte Carlo techniques. The developed program allows probabilistic predictions of Voltages profiles at all buses or nodes of a Distribution Networks. A practical case is also discussed to show the application of the study in order to assess the maximum Photovoltaic power penetration that can be installed into a Distribution Network without violating Voltage Constraints. [ABSTRACT FROM AUTHOR]

Abstract: Renewable energy which independent power generation systems from the nets is increasingly extensive research and application. This paper is in connection with ac distribution problems of village, it is with the foundation of multiple national''s standard and field operation experience. From lines in-station, transmission and distribution line, distribution cabinets and other power distribution equipment structure, function, capacity selection, and so on, this paper has a positive research summary and elaboration, can provide the beneficial reference for relevant standards. [Copyright &y& Elsevier]

Abstract: Estuarine processes have long been important to oceanographic researcher. The closeness of estuaries to land & the diversity of physical activity found within them have stimulated interest in estuaries as individual systems. An overview of the current design practices in the field of renewable energy is presented; also paper delineates the background to the development of unique & novel techniques for power generation using the kinetic energy of tidal streams & other marine currents. Tidal stream devices have been developed as an alternative method of extracting the energy from the tides. This form of tidal power technology poses less threat to the environment & does not face the same limiting factors associated with tidal barrage schemes, therefore making it a more feasible method of electricity production. Universally the tides can be harness with tidal turbines- of which there are two main bifurcation-vertical axis & horizontal axis. In this paper only the vertical axis tidal turbine is focused. Some suggestion & corrosion prevention techniques are also discussed in this study. In addition, the progression of technological advancements tracing several decades of R&D efforts on vertical axis turbines are highlighted. The purpose of this review paper is to build up a confidence level for further study in this field in depth. [Copyright &y& Elsevier]

Abstract: This paper presents a review of biomass energy dependency in Tanzania. The study was conducted based on the available literature on energy and biomass in Tanzania. Energy is essential to meet the most basic needs: cooking, boiling water, lighting, and heating. It is also a prerequisite for good health, a reality that has been largely ignored by the world community. More than 80% of Tanzanians depend on biomass as a source of energy by burning firewood, dung, and other traditional fuels. Biomass use accounts for over 90% of total energy consumption. In recent years biomass energy activities mainly firewood wood and charcoal have increased dramatically and the rapid population growth of both urban and rural areas, however, has placed severe strain on the biomass resources, which has led to desertification and deforestation of some areas. This paper reveals that one way of economizing on firewood and charcoal use is to improve their production methods and the use of energy efficient stoves. In addition, the use of alternative energy sources such as liquefied petroleum gas (LPG) and biogas reduces the frequent use of firewood and charcoal and consequently the burden on the forest resources. [Copyright &y& Elsevier]

Abstract: Wind energy is the current “star” in the field of renewable energy for electrical production. Still, the power generated by wind turbines over time is characteristically uneven due to the unpredictable nature of their primary source of power. This only increases the problems inherent to the integration of a great number of wind turbines into power networks, making their contribution rather difficult to manage (regulating voltage and frequency, wind-farm operation, etc.) The integration of wind power in the power system is now an issue in order to optimize the utilization of the resource and in order to continue the high rate of installation of wind generating capacity, which is necessary in order to achieve the goals of sustainability and security of supply. This paper presents the main technical challenges that are associated with the integration of wind power into power systems. These challenges include effects of wind power on the power system, the power system operating cost, power quality and power imbalances (stability of grid). In addition, the paper presents the solutions will be offered to improve the management of wind power generation and increase its penetration in the overall electrical energy production. [Copyright &y& Elsevier]

Abstract: With the economic development, the demond for energy is growing in China, and the traditional non-renewable energy makes the energy transformation is imminent.In this paper, based on the fully understanding of our existing energy structure, and from the perspective of supply and demand, the author analysis the changes in the structure of future energy and gives the suggestion.The paper argues that China''s energy structure will gradually turn to be comprehensive and diverse, but the cost and market constraints will obstruct the promotion of renewable energy sources.Therefore, the traditional high-carbon energy is still the main form of domestic energy consumptionin a very long period of time.Only by improving technology and using of the macro-control can reduce the costs and regulate the import and export, which can achieve sustainable development of changing from a high-carbon energy to low carbon. [Copyright &y& Elsevier]

Abstract: The Netherlands is both heavily dependent on the success of carbon capture and storage (CCS) and renewable electricity for its decarbonisation policy. The same holds for the EU and some of its Member States like the United Kingdom. This paper discusses several scenarios for the Netherlands within the context of a liberalised and a more and more connected energy market in Northwest-Europe. The research reported here shows that CCS on new coal fired power plants does not pose a threat to the increase in the electricity production by large quantities of wind energy in the electricity system, and vice versa. For renewable energy, several additional policies are in place mainly in the form of financial support as long as these renewable options are not yet profitable. For CCS, financial support is only granted now for a selection of the first demonstration projects now planned in the EU. It is not yet clear if large scale CCS and high shares of wind energy can be incorporated in a balanced way in the electricity system. This paper shows that from a technical and economic point of view, there is room for both, and under which conditions such a two fold growth will be feasible. [Copyright &y& Elsevier]

Abstract: The IEA CCS Roadmap highlighted the significance that CCS will need to play in achieving an atmospheric CO2 concentration stabilization of 450 ppm. In the scenario it is based on, CCS will provide approximately 20% of the total CO2 emissions reductions out to 2050. Achieving this contribution of emissions reductions will require an ambitious CCS growth-path, with 100 projects needed globally by 2020 and over 3000 by 2050. In both 2020 and 2050 the major developing countries, including South Africa will need to contribute to CCS deployment. South Africa has a heavily coal-dependent economy with 94 % of electricity production coming from coal. In addition to this, South Africa also meets approximately 30% of its domestic fuel -oil demand through the conversion o f coal and gas to transportation fuels. The combination of these two factors means that South Africa is as dependant on coal as any country in the world, placing the country as the 13th largest CO2 emitter in the world. Currently South Africa is experiencing electricity shortages where the reserve margin is below desired levels on a daily basis. Consequently, deployment of electricity generation capacity is seen as a priority. With the slow development of renewable energy and the deployment of nuclear energy currently under review, the required short term increase in electricity production is likely to come from new, coal plant that will be expected to be in operation for 50–60 years, thus continuing the country’s dependence on coal for some time to come. At the climate change negotiations in Copenhagen, South Africa announced that it would take nationally appropriate mitigation actions to enable a reduction in national GHG emissions equating to a deviation of 34% below the “Business as Usual” emissions growth trajectory by 2020 and a 42% deviation below the below “Business as Usual” emissions growth trajectory by 2025, pended upon the provision of sufficient funding and technology support. Given all these factors, CCS could be a crucial technology for South Africa in the near future. This paper looks to discuss the current status of CCS in South Africa. This includes looking at the key outcomes of the recently released South African CCS Research and Development Roadmap and the milestones it outlines, such as the development of a geological storage atlas by 2010, a CO2 test injection by 2016, and a demonstration project operating by 2020. It also looks at how the South African government is positioned toward CCS, including how CCS fits with the countries priorities of poverty alleviation, economic growth, sustainable development, job creation and ensuring the most efficient use of domestic resources. In addition the paper looks at the manner in which the South African government could go about regulating the operation of CCS projects. The paper will discuss the options available to South Africa to fund CCS demonstration and deployment domestically including via the clean development mechanism (in the event that the question of using this mechanism in the CCS context is dealt with at the international level), development banks and other, appropriate, development finance institutions. Public awareness and engagement on CCS will also be covered, given the crucial role the public play in the smooth progress of projects. Finally the paper will look at international collaboration on CCS including the role South Africa can play internationally and what more the international CCS community can offer. [Copyright &y& Elsevier]

Abstract: In the UK, the Committee of Climate Change (CCC) concluded that in order to meet the 80% emission reduction target set for 2050, the power sector would need to be largely decarbonised by 2030. As the emission reduction required by 2030 is substantial, it is likely to require contributions from renewable, nuclear and CCS. By 2030, any plant running for extended periods will probably have to be able to achieve annual average emissions levels of 100 gCO2/kWh or below vs. the present level of 560 gCO2/kWh. In this context, the new regulations by Department of Energy and Climate Change (DECC) for making power plants CO2 capture ready apply to all combustion plants at or above 300 MW output in the UK. As emissions levels for new built CCGT plants without carbon capture are today around 350 kgCO2/MWh, it is expected that they will not be able to operate without CCS beyond 2030. In order to avoid the deployment of ‘unabated’ gas-fired plants, requirements to fit CCS not only to coal but to gas-fired plants need to be adopted to prevent any inconsistency. Once built, it would be very costly or even infeasible to retrofit the new facilities with CCS, thus “locking-in” many years of CO2 emissions. Currently in the UK there are no new unabated coal plants under construction, whilst around 4.7 GW of new gas plants are expected to come online over the next few years. As in the UK there are a significant number of CCGT power stations recently permitted or waiting to be granted consent they have been required to be CCR so that CCS can be retrofitted once it is commercially viable. It is therefore of a paramount importance to understand what are the feasible options/issues when CO2 capture is applied to the CCGT units. This paper is focusing on capture consideration based on post-combustion technology, the most mature option today. When a CCGT plant is designed to be ready for retrofit one of the most important technical consideration is the steam extraction pressure and flow to provide the energy necessary for solvent regeneration as this will have a large impact on the overall plant efficiency. Available options for steam and electricity supply to meet the requirements of the CCS process have been assessed, focusing on two scenarios–integration scenario where the steam is supplied from the main plant and separate generation scenario where steam is supplied from auxiliary boilers with electricity supplied from the grid connection. The findings of this paper are relevant to project developers, power generators and policymakers internationally who have an interest in the potential for CCS to provide an emissions abatement option for the new CCGT assets in the long term. [Copyright &y& Elsevier]

Cross flow micro turbines are environmentally friendly equipment. A low head Banki turbine is studied in this paper numerically and experimentally in order to identify the reasons why the turbine efficiency is poor at low rotational speeds. A procedure that consists in dividing the flow domain into different zones is proposed for clarifying the main issues. The turbine efficiency obtained experimentally is explained based on a CFD analysis that highlights the influence of recirculation phenomena and shock losses produced when the water jet impinges on the shaft. This analysis is also used to propose a device for internal flow control. [ABSTRACT FROM AUTHOR]

The two main characteristic attributes of power plants based on renewable energy sources (RES) like wind power (WT) or photovoltaic (PV) are the fluctuating power generation and the geographical location of installation. Thus, the RES feed-in is neither adaptive to the time characteristics nor to the geographical location of electric loads. However, these characteristic attributes are not yet considered in today’s market structure and RES promotion is usually based on energy production with no regard to local load curves or the location of installation. On the other hand, these two characteristic attributes lead to voltage and overload issues in the grid, expensive backup power plants and complex system operation. Therefore, this paper proposed an analytical assessment method for RES concerning their merits for the electric power system. The objective was to quantify and compare the merits of different RES installations both regarding time and geographical location. The approach comprised the analytical derivation of the assessment parameters and the application on different RES configurations including energy storage systems (ESS). The assessment showed increased merits for the electric power system, if RES are combined with ESS or with other RES installations to common grid coupling points. In this regard, the proposed assessment method helps to optimize grid integration, operation and control of RES and to promote new technologies like ESS. [ABSTRACT FROM AUTHOR]

In the near future, Electric Vehicles (EVs’) penetration is expected to rise, making the study of their local level effects imperative. EVs is a new, promising, technology which will offer cleaner and more effective means of transportation. On the other hand, EVs can also act as storage devices, thus offering ancillary services to the grid. The optimum operation of Low Voltage (LV) grids, with special emphasis on Smart Microgrids (SM), must be ensured and the financial viability of EVs’ penetration is to be assessed. Smart Microgrids seem to be the best solution for the management of modern LV grids with Distributed Energy Resources (DER). The main purpose of this paper is to investigate the economic benefits that can arise from the coordinated control of DER and EVs in SM operation. Absence of distributed resources, and therefore satisfaction of the full load from the upstream network, is considered as the base case. Various pricing policies based on System Marginal Prices (SMPs) are considered. For each scenario, three different charging technologies are examined. All different cases are compared between them to determine which one is the most advantageous in terms of operational cost. [ABSTRACT FROM AUTHOR]

Nowadays, the urgent need to reduce emissions has led to the development of Renewable Energy Sources (RES). Wind energy via Wind Generators is a very common RES, which, however, is characterized by great intermittency. Consequently, wind energy production may vary from zero to excessive (way above the load demand), which makes wind power plants’ penetration very difficult, making the need for energy storage essential. On the other hand, Electric Vehicles (EVs) offer a new, eco-friendly and more effective means of transportation. The energy stored in their batteries is used to move the EVs. Nevertheless, the penetration of EVs will increase the energy demand from Thermal Plants, and will therefore harm the environment unless it is combined with an increased RES integration. The advantages of combined use of RES and EVs are evident. EVs can augment Wind Power Plants penetration through their storage capabilities and use some of their excessive wind energy output for environmental-friendly mobility. In this paper, the combination of EVs, RES (Wind Generators) and Thermal Plants of an island is examined as an alternative for the future grids. Two scenarios are being studied with focus on peak shaving. Taking into account the Medium Voltage (MV) line load demand, wind power and thermal units output hourly data in a yearly basis, a special algorithm is developed so as to study the case of absorbing the excess energy via off peak charging and reintroducing it into the Microgrid scheme in peak demand periods. The studies are conducted for two cases: a) low penetration and b) high penetration of EVs. All findings are thoroughly discussed in conclusions section. [ABSTRACT FROM AUTHOR]

The conventional design of ground source heat pumps (GSHPs) is based on the peak heating and cooling loads. A possible optimization in GSHP design, including a thermal storage device between the ground exchangers and the heat pump, was already realized and it was found that a reduced-size geothermal field (-66%) is still able to cover the energy demand. In this paper, the design of the prototype was used as a starting point to study the potentialities of two possible upgrades for the optimization of the energy performance (COP) of the system. In the first case, the thermal storing material is water, as in the working prototype, and the efficiency is improved removing the cylindrical heat exchangers that were designed to separate the ground side from the heat pump side. In the second case, a completely new and more compact thermal storage was designed using phase change materials (PCMs). Computational fluid dynamics (CFD) simulations were performed in a transient regime to validate the model against observed data and to assess the potentiality of the two improvements. The system behavior is studied in terms of driving energy input and output energy production. Significant improvements of the system COP are observed (up to +20%). In the first case (water thermal storage), the overall COP is 4.1 during winter and 5.7 during summer, in the second case (PCM thermal storage), the COP is 4.1 and 5.9, respectively. The PCM thermal storage, in particular, is approximately 10 times smaller than the original design, and could be easily placed within the technical room. [ABSTRACT FROM AUTHOR]

In the present paper, an energy storage concept based on the integration of a Compressed Air Energy Storage system into a Gas Steam Combined Cycle plants is investigated. The integration of CAES results in a noticeable power augmentation in respect to normal GSCC plant operations. Being such a power increase obtained without using additional fuel, the storage system can be compared to PHS, BES and A-CAES. Two CAES integrated into medium size GSCC plants arranged with Aero Derivative and Heavy Duty Gas Turbines have been investigated. A techno economic analysis aimed at assessing plant performance and investment costs has been performed. Despite the relatively high investment costs and the storage efficiency lesser than those featuring alternative storage approaches, the proposed system may be considered of interest due to the long life duration and the established technologies available for the key plant components. [ABSTRACT FROM AUTHOR]

To answer the actual energy, water, economic, social and environmental challenges, renewable, distributed power plants need to be developed. Among renewables, solar tri-generative power plants can be a solution where there is big low temperature heating/cooling demand and small electricity demand, like many residential and industrial utilities. In this case, solar thermal plants can produce thermal energy with low cost and high efficiency. The higher temperature heat not needed by the user can be exploited via Organic Rankine Cycle to produce electrical energy and desalinized water via reverse osmosis. The present paper analyses, via TRNSYS simulation, a system composed of 50 m 2 of CPC solar thermal collectors, 3 m 3 of thermal storage, a synthetic heat transfer fluid, 3 kW e ORC, 8 kW th absorber, 200 l/h direct reverse osmosis desalination device. The system is able to produce power, heating/cooling and fresh water needs for a residential house. Although system's components are well known technologies, the integration to a efficient and economic working system is still a challenge. Global energy and economic analyses have been performed. Low temperature heating/cooling terminals allow to increase not only the use of thermal energy but also the ORCand absorber efficiency. ORC-Absorber configuration and relative fluids and temperatures are central. Government support and/or cost reduction of 30% are necessary to have positive NPV and acceptable PBT and IRR. [ABSTRACT FROM AUTHOR]

In connection with the “IEA SHC Task 47 - Solar Renovation of Non-Residential Buildings”, Denmark has investigated 4 exemplary renovation projects; The Osram Culture Centre, Rockwool office building, Parkvænget office building and Kindergarten Vejtoften. The 4 exemplary projects have demonstrated that deep energy renovation can be achieved for different types of non-residential buildings including protected/historic buildings through combinations of energy efficiency measures and renewable energy measures. This paper provides an introduction to the IEA project and includes results from the 4 Danish exemplary projects with a more detailed description of the renovation of Parkvænget office building. [ABSTRACT FROM AUTHOR]

Abstract: The indoor climate control of buildings represents today the highest percentage of energy consumption in European Union. Hence the evaluation of the best performing HVAC system is a strategic target for both energy consumption and greenhouse gas emissions reduction. This paper presents a deep analysis of the performance of Renewable Energy Sources HVAC systems for buildings. The technologies considered are biomass boiler, aerothermal, geothermal and absorption heat pumps. The proposed method estimates all the parameters according to the theory of the “big is better”. For each parameter a function has been defined to evaluate how much the performance of each technology depends from it. The analysis take in account also the environment in which each technology operates. The result is a set of dimensionless parameters, through which it is possible to extrapolate the assessments of performance. It can include both cost-effectiveness and feasibility of a given technology and the contribution to the achievement of European objectives to 2020. [Copyright &y& Elsevier]

Abstract: Domestic water heating in Australia conventionally uses electric resistance heating storage or gas fuelled water heaters. The Australian electricity supply has some of the highest greenhouse gas emissions factors in the world. Consequently, water heating is responsible for approximately 24 percent of residential sector greenhouse gas emissions in Australia. To assist households to move towards an energy efficient, low carbon future, a suite of market intervention programs to support solar hot water uptake have been introduced at both state and federal levels. These programs aim to improve the capacity of industry to deliver solar solutions, reduce the emissions intensity and net cost of household water heating, and increase the market share of the solar water heating sector. Incentives include: [•] Point of sale rebates and certificate-based programs for energy efficiency and renewable energy; [•] Regulations for new houses that encourage solar water heating installations; [•] Community awareness programs; and [•] Training programs for installers to ensure that tradespeople have the competencies to size systems and the skills to install them correctly. In some jurisdictions the incentive programs were performance-based, but in others a fixed rebate amount was available for all systems having performance above a minimum threshold. These programs have lead to the widespread expansion of the industry, with an almost doubling of the proportion of households with solar water heaters between 1999 and 2011. Installations in new homes have seen an even more marked increase: For example, regulations for new homes in the state of Victoria require the installation of a solar water heater or rainwater tank. This program has seen the adoption of solar water heaters in new homes increase fro m around 5% in 2004 to over 70% in 2011. Across most of Australia there are proposed regulations limiting the emissions intensity of replacement water heaters which will effectively ban resistance electric water heaters in most situations. Recently both South Australia and Queensland commenced their program for existing houses. It is expected that in the future these programs will drive an even greater uptake, which will go some way to insulating Australian households from price increases that may result from carbon driven future increases in the cost of energy. This paper discusses the various approaches and outcomes of the different programs and provides analysis of the basis of program success or improvements. Learning relevant to market interventions worldwide include [•] Continuity in program operation is necessary to allow industry to grow in a sustainable way. [•] Basing the incentive on independently derived performance results provides industry with a means of differentiating better products and provides purchasers with appropriate guidance. [•] Rebate program design should consider the consumer''s purchasing priorities. For example, a point of sale discount awarded as part of the purchase transaction aligns with the urgency of the purchasing process and does not require additional cash to be available from the purchaser. [•] Design of the schemes can not only produce a greater market share, but can also encourage the manufacture of lower greenhouse gas emissions products. [•] Market interventions can have unintended consequences, so the programs need to be monitored and flexibility maintained to changes to avoid poor outcomes. [Copyright &y& Elsevier]

Abstract: This paper provides an overview of Subtask B: Tools and methods for solar design, of IEA SHC Task 41: Solar energy and architecture, 2009-2012. The focus of this Subtask was on identifying obstacles that architects are facing when implementing passive and active solar strategies in their design, especially during the early design phase (EDP) of building projects. The results of this Subtask also aim to provide strategies and resources for practitioners regarding the use of different digital tools and design methods for solar design. [Copyright &y& Elsevier]

Abstract: The objective of Task 44 of the Solar Heating and Cooling program of the IEA is to assess performances and relevance of combined systems using solar thermal and heat pumps, to provide a common definition of performances of such systems, and to contribute to successful market penetration of these new promising combinations of renewable technologies. The Task is also Annex 38 of the Heat pump program and thus called T44A38. It gathers 12 countries and 55 participants.This paper presents the mid term results of the activity, which started in January 2010 and will last until December 2013. [Copyright &y& Elsevier]

Abstract: Energy efficient HVAC solutions may be obtained by combining different energy sources – fossil and renewable – into single hybrid systems. This leads to a variety of system concepts with specific boundary conditions. As a consequence, the definition of a unique representation method and a standardized performance evaluation procedure is a challenging task. Currently, two international projects promoted by the IEA are dealing with the representation and the performance calculation of a particular category of hybrid systems, i.e. integrated solar assisted systems. The HPP Annex 34 “Thermally Driven Heat Pumps for Heating and Cooling”, whose goal is to reduce the environmental impact of heating and cooling by the use of thermally driven heat pumps, has solar cooling as one of the systems under investigation. The joint project between SHC and HPP Task 44/Annex 38 “Solar and Heat Pump Systems” is focused on different system combinations of solar thermal collectors and heat pumps. The scope of the present paper is to show a systematic methodology to represent and evaluate the energy performance of complex hybrid systems. The proposed approach is a joint effort of the on-going IEA activities and will be discussed regarding the mentioned solar hybrid systems. However, the final goal of the work is to provide a basis for a simple, fair and transparent comparison of all systems for heating and cooling, regardless of the technology. [Copyright &y& Elsevier]

Abstract: This paper presents the major outcome of the IEA Hydrogen Implementing Agreement (IEA-HIA) Task 23 “Small-scale reforming for on-site hydrogen supply”. The task is briefly described, including the three sub-tasks: harmonized industrialization, sustainability and renewables and market information. An exclusive network of worldwide suppliers of reformers as well as gas companies has contributed to the discussion, evaluation and harmonization of on-site production technologies and optimal use of feedstock. The ambition has been to contribute to harmonization of capacities and improved system performance to facilitate both reduced system and production costs. [Copyright &y& Elsevier]

Abstract: The International Energy Agency Hydrogen Implementing Agreement (IEA HIA) is the world''s largest and longest-lived cooperative organization in hydrogen research. It offers researchers an established, global network and acts as a catalyst and framework for collaboration. The IEA HIA''s core business is hydrogen R,D&D. Our vision is a hydrogen future based on a clean sustainable energy supply of global proportions that plays a key role in all sectors of the economy. This paper provides an overview of the IEA HIA collaboration and our eleven (11) current/closing tasks, emphasizing the role of research and analysis that enables hydrogen energy solutions. [Copyright &y& Elsevier]

Abstract: In order to reduce the green house gas emissions all over the world the investment on renewable energy infrastructure is increasing particularly in the distribution network. The penetration of generating sources in the distribution network changes the characteristics of distribution system and will have impact on various technical parameters based on its size and location in the network. This paper modeled the IEEE 34 Node distribution test feeder using the commercial software package DIgSILENT power factory version 14. Solar photovoltaic generators are introduced as Distributed Generators (DGs) at various nodes and the impacts that DG produces on real and reactive power losses, voltage profile, phase imbalance and fault level of distribution system is studied. Simulated results obtained using load flow and short circuit studies are presented and discussed. [Copyright &y& Elsevier]

Abstract: Literature on knowledge and knowledge integration has mainly focused on its importance for firms and companies, but we should not forget the importance of knowledge for value creation for the society as a whole. The main focus in this paper is to discuss academic-industry collaboration through the concept ‘Mode 2’, which will be connected and discussed in relation to the Norwegian Centres for Environment-friendly Energy Research (CEER) scheme. This is accomplished through an analysis of the Norwegian CEER scheme in relations to the five attributes of ‘Mode 2’. It is evident that the research program has picked up several suggestions from the latter. However, the analysis also shows that the CEER scheme is mixed with regard to ‘Mode 2’ and ‘Mode 2’ on several attributions. The mixed approach is illustrated by the objectives for the CEERs, which is set by the Research Council. The research in CEERs should at the same time both be disciplinary scientific and applied by companies. This analysis is supplemented with a short review of some empirical studies of the ‘Mode 2’ phenomena’. Based on these studies it is apparent that there is a need for further empirical investigation of empirical micro-dynamic of collaboration between academia, industry and government. It is suggested that empirical investigation should apply the framework of Tell , to understand knowledge integration between academics and people working in enterprises collaborating within a CEER. This should enable us to identify best practice and improved design in the CEER scheme that will enable better commercialization of innovations. [Copyright &y& Elsevier]

Abstract: Renewable energy sources play a role in providing energy services in a sustainable manner. In this paper, we review and estimate the renewable electricity potentials in France in a long term perspective, considering technical as well as social acceptability factors. Previous assessment studies are reviewed, and specific evaluations are conducted to estimate both the solar electricity potential on residential rooftops and the wind electricity potential in likely-developable areas. Potential effects on the grid power balance are examined for typical winter and summer days based on historical data sets. France has the resources to produce a large portion of its annual final electricity consumption with renewable energy. However, further analysis is needed to evaluate more in depth the influence of limiting factors such as the variability of certain resources, the distribution and transmission constraints, and the potential usage conflicts. [Copyright &y& Elsevier]

Abstract: The switch from a mined-carbon-based society to a bio-carbon based society requires a major shift not only of the resources,but alsoin the typeof processes that produce the products on which ourcivilizationbuilds;a richer approach to handling and production is required. Natural products from renewable sources will substitute today''spurely synthetic products from fossil resources, associated waste streams will have to be utilized for the production of usable materials, with chemical processing being one of the main options.Fuel represents a main class of chemicals that we increasingly rely on. They have to be substituted as quick as possible as they represent the largest use of mined carbon. The paper presents some of the stumbling blocks which prohibit the transfer and high lights the most needed research objectives. [Copyright &y& Elsevier]

Abstract: This paper discuss role of cooperations in creating opportunities for using rich renewable energy sources and also their potential role for entrepreneurship and employment in Iran. The presence of constant, sustainable and economical energy is an essential basis for any economical and social development while it can upgrade life qualities. Iran has a considerable amount of natural resources for modernizing its energy supply and being transited to a sustainable energy system as it has countless opportunities for using rich renewable energy sources. On the other hand, cooperation have been considered as a strategic way to create job opportunities as they are strong organizations which can encounter economical and social side affects caused by quick moderating procedures in structural programs. Results show convergence between renewable sources development and Iran''s economical development through taking a frugal approach in expenses, creating new job opportunities and entrepreneurship in renewable energies. [Copyright &y& Elsevier]

Abstract: This paper presents a new topology of three-level single phase photovoltaic (PV) and wind power hybrid inverter. It consists of three main circuits; they are a hybrid controller circuit, a charger circuit, a pulse driver and full bridge circuit. The inverter is installed in front of Electrical Energy and Industrial Electronic Systems (EEIES) Cluster, Universiti Malaysia Perlis, Northern Malaysia. Its main energy source is a PV array and wind power generation. In this research, AC three-level waveform and square wave single phase PV and wind power hybrid inverter are developed and created by a microcontroller PIC16F627A-I/P and analyzed their performance comparisons. The result shows that the AC waveform which is formed by the PV and wind power hybrid inverter will effect on AC load rms voltage, AC current and current total harmonic distortion (CTHD), for a load of 20W 220V 50Hz AC water pump, its AC load rms voltage and current are higher when the single phase PV and wind power hybrid inverter is formed as AC square wave than as AC three-level waveform, but the CTHD is lower when the single phase PV and wind power hybrid inverter is formed as AC three-level waveform than as AC square wave. [Copyright &y& Elsevier]

Abstract: Talking about the concept of “environment” means treating a multidisciplinary and interdisciplinary theme which revives a simultaneous consideration of multiple data social, economic, natural. To date, the protection of the environment as a whole becomes a challenge for many countries, policies for the preservation, education and scientific research strategies are aimed at the environment and sustainable development. It remains an idea of its young problem, still current. It is development that meets present needs without compromising the ability of future generations to meet their own needs. In the field of architecture and urban planning, environmental protection is an important place. With the growth experienced by this area, several environmental procedures have been invented to improve the quality of construction and use of buildings, a view mainly environmental but without neglecting the economic and social aspects. The environmental protection has long existed, it is found in the experiences of ancient cities such as Ksours. This legacy is an inspiration and an asset for the sustainable development of our cities today. According to Hassan Fathy only in the tradition, we respect and we continue the work of previous generation that new generation can really move and solve the problem. The materials used the distribution of space, protection of natural resources such as water and palm trees, recycling, are the strategies of the company of Ksours to live in a healthy and comfortable space. The objectives of this paper are: To highlight the history of environmental policy in architecture and urbanism in the world, in this case Ksours. Renewable energy and strategies of the preservation of the environment in the Ksours Sustainable development in Ksours: a notion that has long existed. Establish strategies to protect the environment. [Copyright &y& Elsevier]

The urbanized surface of the old continents could be double in little more than a century due to the transit of the _world from villages to cities (according to the UN) beside the rapid growing in the world population, these will lead _to large numbers of environmental problems, one of these problems is that the energy consumption per person will _increase so more energy will be produced. ^pElectricity from fossil fuels such as oil, coal and natural gas negatively affect the environment at each step from production till consumption, and relaying mainly on these resources of energy to apply this new huge demand will lead to producing more CO2 gas in the atmosphere which will case rising of earth temperature in a rapid rate while electricity generated using sources other than fossil fuel reduces the environmental impacts. Buildings consumes approximately 39% of the energy and 74% of the electricity produced annually in the United States (according to LEED BD+C version 3), and as a rule of thumb the better the energy performance of a building, the fewer greenhouse gases are emitted, So relying on renewable energies to supply urban areas with the power needed is the solution for this problem and is considered an important approach for our cities to be more sustainable. The major shift in the vision of sustainable cities is the potential of buildings to produce energy. This will entail a whole host of solutions (solar, wind power and so forth) that will make cities more interesting as well as sustainable. And in this paper we will try to introduce the main parameters and considerations of these renewable energies specially the wind energy which can affect the form of the city and the important dimensions that should be taken into consideration when designing a new sustainable city. [ABSTRACT FROM AUTHOR]

Abstract: With the concern about the issues of global environments and climates, the green power development is drawing increasing attention. Although the government of our country attaches great importance to renewable energy power generation industry and certain industry foundation has been established, the generating costs of green power obviously lack competitive advantages comparing with those of the tradition power. As a result, the developing speed is relatively slow. This paper analyzes the existing barriers in the green power development of our country and puts up the suggestions of developing strategies for the future green power of our country, combined with the actual situations of our power industry. [Copyright &y& Elsevier]

Abstract: Photovoltaic (PV) systems can be tied to a utility grid to work more effectively as an alternative energy sources. One of the major issues about grid-tied PV systems is to avoid non-intentional operation in islanding mode. Many methods have been proposed to detect islanding operation of grid-tied PV systems. They have different non-detection zones for different kinds of load. This paper presents an intelligent adaptive method for islanding detection in grid-tied PV system. The simulation and test results prove its effectiveness and superiority. [Copyright &y& Elsevier]

Abstract: The combination of cascade control and local control is proposed as a method to compensate power fluctuations caused by load and renewable energy sources in a microgrid with distributed power generation systems- (DGs).The use of energy storage system(ESS) such as EDLC facilitates power ompensation. However, since the energy capacities of these components are limited, the contol of their state of charge(SoC) is necessary. This paper addresses real and reactive power management strategies of electronically interfaced distributed generation(DG)units in the context of a multiple-DG microgrid system,and a new method to control ESS''s SoC which would enable power compensation with less energy capacity and with less effect to the compensation result is proposed. [Copyright &y& Elsevier]

Abstract: Ground-source heat pump (GSHP) is a renewable energy technology with the advantages of energy saving and environmental friendliness. This paper focuses on the energy efficiency of air-conditioning systems in public buildings in Tianjin. Three public buildings are chosen as case studies with different forms of cold & heat sources. A building with ground-source heat pump for heating and cooling, a building with electricity-driven refrigerating unit for cooling and centralized heat-supply network for heating, a building with direct-fired Li-Br absorption refrigerating and heating unit for heating and cooling are selected. Attempt is made to analyze the actual operating performance of air-conditioning system and evaluate the system energy efficiency in different buildings. The results show that ground-source heat pump air-conditioning system without adequate design and management is not always better than other traditional air-conditioning systems. [Copyright &y& Elsevier]

Abstract: Click In the background of global financial crisis and abnormal climate, low-carbon economy has become an optimal choice for the sustainable development of all countries. The biomass based power generation industry is an important way of developing low-carbon economy as well as a way of improving the energy structure of China. As a renewable energy, biomass power has a rapid growth in the last few decades in China. This industry faces opportunities as well as challenges for development. Using SWOT analysis method, this paper reviews and assesses the factors of strengths, weaknesses, opportunities, and threats of biomass power generation industry of China. Meanwhile, according to the weaknesses and threats of this industry, it comes up with corresponding suggestions for future work, substantial work is still required for China to catch up with developed countries. Finally, study indicated that the usage of biomass to generate power has great potential for development in China. [Copyright &y& Elsevier]

Abstract: The hybrid power sources, particularly type renewable is one of advanced solutions in the field of energy including wind-photovoltaic type, designed to ensure reliability of system operation or chain energy conversion with better management and control. In this paper, we analyze the modeling and simulation of an energy conversion system based on a double-fed induction machine (DFIM) powered by a hybrid renewable source. The results obtained are very advanced and satisfactory. [Copyright &y& Elsevier]

Abstract: MicroSources and Renewable Energy sources refers to Distributed energy resources(DERs) and MicroGrids refers to a distribution network for electrical energy,starting from electricity generation to its transmission and storage with the ability to respond to dynamic changes on energy supply through co-generation and demand adjustment.Utilising potential of available distributed energy sources, MicroGrids can provide improved electric service reliability and better power quality to end users of electricity at conservative approach which might not be with the MicroGrids (centralized power grids). A worldwide research is going on MicroGrids, its application and control to overcome the weaknesses of the centralized power grids. In India due to power crisis a heavy load shedding has been carried out since last five years as load demand increasing day by day. Presently the concept of MicroGrids has been utilizing in rural areas of countries namely Canada, US, UK, Kenya etc. India is also having rich potential for Distributed energy resources (DERs). In this paper, potential of Distributed energy resources (DERs) in rural areas of Maharashtra state India has been predicted and suggested how application of Microgrids can reduce energy losses, improve power quality, deliver sustained power by Zero Load Shedding Model. [Copyright &y& Elsevier]

Abstract: For the shortcoming of single air source heat pump, single solar energy heat pump and switch solar-air dual heat source heat pumps, a new solar air two source heat pump was proposed. Then, the performance of the solar air two sources heat pump was studied by experiment. According to the characteristics of heating performance of the solar air two sources heat pump, two important concepts were proposed. The two concepts were “the two heat sources effectively compound heat transfer temperature difference” and “the max two heat sources effectively compound heat transfer temperature difference”. And in this paper, the influence on the heating performance of the two heat sources effectively compound heat transfer temperature difference in different solar hot water flows, and the effect of the two heat sources effectively compound heat transfer temperature difference were researched by experiment and analyzed. The experimental results show, the max two heat sources effectively compound heat transfer temperature difference increased with solar hot water flow decreasing and it decreased with the outdoor air temperature increasing. The solar hot water flow has more influence than the outdoor air flow. [Copyright &y& Elsevier]