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At present, energy represents a key element in the social and economic development of a territory. This is particularly true for fragile territories that are not interconnected, such as small island states. As is true for many of the Small Island Developing States (SIDS) worldwide, the energy situation of the Comoros is substantially based on fossil fuel imports. The socioeconomic development of this archipelago is overwhelmingly dependent on energy security from sustainability, availability and affordability perspectives. As a forward-looking response to energy vulnerability, the deployment of renewables to diversify the generation of electricity appears to be an essential prerequisite for guaranteeing a sustainable future. Nevertheless, despite a high potential for renewable energy, only 3.8% of the electricity supply in the Comoros is provided by hydropower. This paper provides a comprehensive overview of the energy situation throughout the Comoros and focuses on renewable energy opportunities to facilitate the supply of green power. This study ultimately shows that renewable energies are rarely exploited despite the powerful potential of different resources. Finally, this paper attempts to provide recommendations for the Comoros to pursue a more sustainable future. • Analysis of the current energy situation of Comoros. • Defining renewable potential and ongoing actions. • Analysis of the specific barriers and policy to the development of RES in the Comoros. [ABSTRACT FROM AUTHOR]

Short-term forecasting of electricity generation from variable renewable energy sources is not an end in itself but should provide some net benefit to its user. In the case of electricity trading, which is in the focus of this paper, the benefit can be quantified in terms of an improved economic outcome. Although some effort has been made to evaluate and to improve the profitability of electricity forecasts, the understanding of the underlying effects has remained incomplete so far. In this paper, we develop a more comprehensive theoretical framework of the connection between the statistical and the economic properties of day-ahead electricity forecasts. We find that, apart from the accuracy and the bias, which have already been extensively researched, the correlation between the forecast errors and the market price spread determines the economic implications - a phenomenon which we refer to as 'correlation effect'. Our analysis is completed by a case study on solar electricity forecasting in Germany which illustrates the relevance and the limits of both our theoretical framework and the correlation effect. • The economics of short-term electricity forecasts are studied analytically and empirically. • The value and the risk of forecast-based electricity trading are evaluated. • We find that the economics depend on the correlation of forecast errors with prices. • Hence, the most accurate forecast is not necessarily the most accurate. [ABSTRACT FROM AUTHOR]

Despite the importance of cost of capital and expected returns from investing on renewable electricity generation in Africa on one hand and the implications of such investments on economic, social and environmental factors on the other. These concepts are not well understood by non-finance and finance actors respectively. Studies that analyze renewable energy-growth nexus at regional and global level are lacking. Instead, existing studies emphasize on individual countries or panel of countries. The paper undertakes comparisons of costs and returns of selected renewable energy technologies in Africa and presents estimates of its impact on Africa's economic growth between 1990 and 2014. Even with abundant renewable resources and well performing technologies measured using levelized cost of electricity and expected internal rate of return, investment on renewable electricity generation is quite low. Findings from Autoregressive Distributed Lag approach and cointegration established a long run relationship among hydro power generation, carbon emissions and electricity consumption. Error Correction Model results suggest that investment in renewable generations excluding hydro power generation is boosted by economic growth, so long as development of such renewables corresponds with lesser carbon emissions. To accelerate renewable development, SSA countries will need to deploy initiatives that enhances national economic growth. [ABSTRACT FROM AUTHOR]

Renewable energies (RE) in Chile and around the world have experienced outstanding growth in recent years. However, RE technologies such as solar photovoltaic and wind generate an imbalance between generation (offer) and consumption (demand) because of their intermittent and variable nature. Moreover, RE's natural variability makes it necessary for conventional technologies to play a significant role in adjusting for the imbalance in the electric system frequency. As variable RE penetration grows, the need for frequency regulation will increase and, depending on how those higher costs are financed, this could lead to a disincentive to invest in conventional plants that provide that service. In this paper we study the impact of increased photovoltaic energy penetration, the leading RE in Chile, on the profitability of different conventional generation technologies. Specifically, we analyze the role that the frequency control remuneration mechanism has on that impact. For this purpose, four different solar photovoltaic penetration scenarios are simulated in Chile's Northern System, comparing two payment criteria for frequency regulation services: i) a cost-based pricing system whose payments relate to the incurred costs and ii) a market-based pricing system where the marginal cost of providing the services is paid. The results show that as installed photovoltaic capacity increases, the average marginal cost of energy (operation cost) decreases due to a displacement of more expensive power plants, but at the same time, investment cost may increase. In the long run, contract prices change as a result of falling operational costs and rising investment cost, resulting in changes in the profitability of all technologies. Finally, while both cost-based and market-based systems reward the ability to regulate frequency, the technologies performing the regulation receive different payments for the service, affecting both their profitability and the incentives for investment. • High penetration rates of intermittent renewable energies require more frequency regulation services. • Depending on the type of regulation, incentives to invest in technologies providing ancillary services might diminish. • Incentives to invest do not change between a regulatory scheme markedbased compare to one cost-based. • Profitability of the natural gas power plants is the one increasing most under market-based regulation. • Under market-based regulation the profitability of photovoltaic and eolic power plants decreases. [ABSTRACT FROM AUTHOR]

This paper presents an investigation of a 111 MWe linear Fresnel reflector (LFR) plant integrated direct contact membrane distillation (DCMD) system. Both the technologies are synergized by using seawater as cooling fluid in the condenser, and then utilizing heated seawater from the condenser into the DCMD unit. The performance analysis of the LFR plant and DCMD unit has been conducted mainly in regard to direct normal irradiance (DNI) and feed water temperature, respectively. For the LFR plant, electricity generation increased with increasing DNI. The highest and the lowest energy production was 38.33 GWh and 14.08 GWh in June and December, respectively. The real levelized cost of energy was found to be 0.34 ¢/kWh. For DCMD unit, the evaporation efficiency increased from 39.13% to 50.01% corresponding to a feed temperature increase from 30 °C to 45 °C. The average freshwater production capacity of the DCMD unit was found to be 31,844.6 L/day with a water production cost $0.425/m 3 . The investigations revealed that the performance of the proposed system is quite satisfactory, and the low unit production cost of electricity and freshwater make it competitive to eradicate energy and freshwater crises. [ABSTRACT FROM AUTHOR]

Abstract: The use of forest biomass in thermal generation processes has been recognized by the Government of Nova Scotia (NS) as one option that could help meet its renewable electricity goals (25% by 2015 and 40% by 2020). Over half of the woodland in NS is owned by small-private woodland owners (51%), indicating that they could significantly influence the future of NS forests and its potential use for energy purposes. This paper presents the results of a survey of small-woodland owners on their attitudes towards using energy from forest biomass. 489 small-woodland owners responded to mail-out surveys and 14 rural community members participated in three focus groups. Three major findings emerged. First, it was found that the acceptability of using forest products varied depending on multiple factors – the source of biomass, harvesting methods, and [predicted] end-use. Second, forest sustainability and keeping resources local were the two most important concerns amongst respondents. Finally, respondents felt that better collaboration with other stakeholders and education around the issues would be the best strategies for overcoming these concerns. The paper also highlights the barriers and drivers as perceived by the woodland owners as they relate to the possibility of using more biomass for energy in the future. [Copyright &y& Elsevier]

Photovoltaic thermal system (PV/T) is one of the promising technologies in renewable energy field. It uses sunlight and simultaneously produces electricity and hot fluid for thermal applications. PV/T system is composed of different elements that can affect both efficiency and cost of the system. A designer can introduce various systems with different combinations of elements. In this paper a multi-attribute decision making (MADM) model is designed to determine influence of each element type on the efficiency and cost. A multilevel network is developed and analytical network process (ANP) is employed. Two main criteria are system efficiency and initial cost of production. The efficiency criterion has 7 sub-criteria and any of them has some sub-sub-criteria. There are also sub-sub-sub-criteria level in some parts of the network. Importance of cost to efficiency depends on the decision maker's demands, so it has been assumed that their importance is equal. All the other network data has been gathered from relevant scientific references. The demonstrated model introduces a screening tool to choose among different PV/T systems. Eleven PV/T systems constructed in Asia are considered as alternatives and the best of them and an ideal alternative are introduced. [ABSTRACT FROM AUTHOR]

Abstract: This paper assesses the potential of harnessing solar radiation in different regions of Iran. In this regard, solar radiation maps are generated for five different cases: total radiation on a south facing fixed surface tilted at the latitude angle; total radiation on a surface tilted at the latitude angle with East–West tracking; total radiation on a surface tilted at the latitude angle with azimuth tracking; direct beam radiation on a horizontal surface with East–West tracking; and direct beam radiation on a surface with two axis tracking. The first three cases are generally applicable to photovoltaic (PV) power plants while the last two are generally used for concentrating solar power (CSP) plant design. In the second part of the paper, a 5 MW PV power plant is considered for 50 cities of Iran. Capacity factors, electricity generated and annual greenhouse gases emission reductions are compared. The results show a great potential for central and southern parts of the country. [Copyright &y& Elsevier]

The work reported here addresses load matching improvement in Net Zero Energy Buildings (Net-ZEBs). The related relevant literature shows that currently research work is mainly focused on improving the load matching of individual buildings. In this paper the concept of a Cooperative Net Zero Energy Community (CNet-ZEC) is introduced, extending discussion to the enhancement of load matching at a wider community level. Both building and community levels are compared in order to assess the work proposed here, through the analysis of three distinct scenarios where five Net-ZEBs work individually or in community. The results presented here were obtained through a detailed simulation based on 1-min resolution stochastic load profiles and recorded weather data. The results indicate that over the period of a year the CNet-ZEC has the potential to increase the electrical demand covered by onsite electricity generation up to 21% and the on-site generation that is used by the building up to 15%. The following elements are considered by the CNet-ZEC in order to produce those results: (i) demand heterogeneity of the buildings integrating the community; (ii) the higher number of controllable devices; and (iii) the potential higher amount of energy available to satisfy the community demand. [ABSTRACT FROM AUTHOR]

Abstract: Electricity generation from renewable sources of energy will be a key part in the development of future strategies for many countries globally. This renewable electricity generation will be hugely important for Ireland, due to its lack of fossil fuel resources. The extremely good wind resource available provides Ireland with the opportunity of generating vast amount of electricity from wind energy. Large-scale wind electricity generation reached 1264 MW installed capacity by January 2010 in Ireland. However, micro scale wind electricity generation has not been very popular in Ireland to-date. The unclear economics of micro wind turbines, under Irish conditions, is considered the biggest obstacle for expanding micro wind turbine installation in Ireland. This paper presents a methodology to accurately evaluate the economic viability of a micro wind turbine on a case-by-case basis. The methodology utilises the software programmes HOMER and Microsoft Excel 2007 for the energy and economic analyses. This paper also presents a realistic economic analysis of a number of micro wind turbines available in Ireland. [Copyright &y& Elsevier]

Abstract: Despite possessing a very large potential of renewable energy sources, Australia has lagged behind other developed countries in embracing renewable energy. Various programs and policies have been devised and implemented by Australian governments. Nevertheless, the proportion of renewable energy in electricity generation in Australia has not increased significantly. This paper seeks to explain why Australia has difficulties in adopting renewable energy by using the Political Aspect of Innovation (PAI) framework to examine the causes and barriers that have blocked the taking up of renewable energy. The PAI framework is concerned specifically with public innovation policy in Australia and the way it aims to encourage and support investment in new technology development. The paper finally outlines some future suggestions for charting the progression of the Australian energy system toward a transformative sustainable future. [Copyright &y& Elsevier]

Abstract: CO2 emissions of the electricity supply sector in China account for about half of the total volume in the country. Thus, reducing CO2 emissions in China’s electricity supply sector will contribute significantly to the efforts of greenhouse gas (GHG) control in the country and the rest of the world. This paper introduces the development status of renewable energy and other main CO2 mitigation options in power generation in China and makes a preliminary prediction of the development of renewable energy in the country for future decades. Besides, based on the situation in China, the paper undertakes a comprehensive analysis of CO2 mitigation costs, mitigation potential, and fossil energy conversation capacity of renewable energy and other mitigation options, through which the influence of renewable energy on the mitigation strategy of China is analyzed. [ABSTRACT FROM AUTHOR]

This paper presents the development stages of a micro-scale system for electricity generation from biomass with 500 W of power. The proposed system is based on an open steam power cycle, whose conception was aimed at seeking solutions to meet the needs for energy supply in isolated communities in the Amazon region. In addition the great biomass potential in the region is an opportunity for the application of biomass energy to increase the economic activity and develop new technologies. The tests performed demonstrate that the steam turbine is the critical component to the commercial-scale feasibility of the presented technology, particularly when it's proposed manufacturing of the system by small regional industries. [ABSTRACT FROM AUTHOR]

This paper applies a life cycle approach to evaluate for the first time the environmental impacts of renewable electricity in Turkey. There are 305 power plants utilising hydro, wind and geothermal resources, all of which are considered in the study. The results indicate that the impacts from large reservoir hydropower are lower than for the small reservoir (by 45%–72%) and run-of-river hydropower (by 74%–84%). The exceptions are the global warming potential (GWP) and summer smog which are two times and 45% higher for large than small reservoir, respectively. Onshore wind is the worst option overall, with nine out of 11 impacts higher than for hydropower and geothermal. However, its GWP is 9 times and 11% lower than for geothermal and large reservoir, respectively. Acidification from geothermal is 281 times higher than for wind power. Geothermal is the best option for six impacts. Large reservoir has the lowest depletion of elements and fossil resources as well as acidification. Small reservoir and run-of-river plants are the best and geothermal the worst options for the GWP. The majority of the annual impacts from the renewable electricity mix are from hydropower with the exception of acidification which is largely from geothermal electricity. [ABSTRACT FROM AUTHOR]

In the last decade a high amount of photovoltaic and wind power generators have been connected to the electric grid, introducing operational problems for transmission and distribution system operators due to the variability and the non-programmability of solar radiation and wind. The paper concerns an analysis on the benefits in adopting storage systems to reduce the imbalance costs associated to renewable energy sources. An analysis on a photovoltaic system has been performed considering different battery technologies. Discrete-time Markov chains have been used to generate a 20 years' time series of irradiance, that has been used to calculate the PV power production. Markov simulation parameters have been deeply studied in order to optimize them and obtain reliable synthetic data of ground irradiance. This data was then used as input of a hybrid PV and storage model allowing to obtain realistic economic and technical results, improving thus the results respect to the methods based on probabilistic weather simulations. An imbalance tariff has been assumed and its cost has been analysed in relation to the storage system costs. An optimal size for the different battery technology has been investigated considering the reduction of variability of the photovoltaic production and the economic convenience of the hybrid system. The use of Markov chains for the optimization of the battery size can be considered as the major novelty of the proposed approach. [ABSTRACT FROM AUTHOR]

Wind-generated electricity is a growing renewable energy resource. Because wind results from the uneven heating (and resulting pressure gradients) of the Earth, future wind resources may be affected by anticipated climate change. Many studies have used global and regional climate models to predict trends in the future wind resource over the continental United States. While some of these studies identified regions that are expected to gain wind energy, their results often come with a high degree of uncertainty, and lack of agreement across different climate models. In this paper we focus on wind energy density as a measure of the available wind resource over the continental United States. We estimate the change in wind energy density from the period 1968–2000 to the period 2038–2070 by using output from four regional climate models from the North American Regional Climate Change Assessment Program (NARCCAP). We find strong agreement across all 4 models that the wind energy resource is expected to increase in parts of Kansas, Oklahoma, and northern Texas – a region already in possession of both large scale generating capacity and political support for wind energy. [ABSTRACT FROM AUTHOR]

The Brazilian government aims at universal electricity access. The national rural electrification initiative has provided electricity services to more than 14 million people since 2003, mainly through grid extension. However, the initiative has not been able to reach remote areas in the Amazon, thus requiring a review of conditions for small scale off-grid power generation projects. As a result, new rules established under the national rural electrification program address the design and implementation of off-grid power generation projects with an installed capacity up to 100 kW. The objective of this paper is to explore the effects of the new set of rules on the levelized cost of electricity for different power generation solutions in the Amazon. Our study shows that the new rules may be beneficial to isolated communities, as they reduce the levelized cost of electricity, favor renewable energy technologies and may contribute to reduce CO 2 emissions. In addition, the new rules may help engage new actors to provide rural electrification of the Amazon region. To fully take advantage of the current scheme, action at local level is required to define the most appropriate model for small-scale power generation projects and establish synergies between concessionaires and local energy providers. [ABSTRACT FROM AUTHOR]

This paper examines the opportunities for the renewable resource of wave energy in Australia's National Electricity Market (NEM). Using 9 years of hourly wave resource data and a typical terminator wave energy converter performance curve, hourly electricity generation profiles and normalised annual wave energy capacity factors were calculated in spatially distributed “polygons” of the NEM. A conservative wave farm design with 3.35 wave energy converters per km, and environmental, marine park and general exclusion zone constraints, has been assumed. The polygon spanning western Victoria has the greatest capacity factor of 0.44. Integrating the hourly electricity generation data revealed that polygons in Tasmania can generate the most electricity, equal to 44.4 TWh/yr. Total generation over all NEM polygons was calculated to be 275 TWh/yr. This exceeds Australia's total electricity generation of 255 TWh for the 2011−2012 financial year. Therefore, wave energy could potentially provide sufficient electricity generation to meet demand in the NEM region. [ABSTRACT FROM AUTHOR]

Electricity generation using renewable energy generation technologies is one of the most practical alternatives for network planners in order to achieve national and international Greenhouse Gas (GHG) emission reduction targets. Renewable Distributed Generation (DG) based Hybrid Energy System (HES) is a sustainable solution for serving electricity demand with reduced GHG emissions. A multi-objective optimisation technique for minimising cost, GHG emissions and generation uncertainty has been proposed in this paper to design HES for sustainable power generation and distribution system planning while considering economic and environmental issues and uncertainty in power availability of renewable resources. Life cycle assessment has been carried out to estimate the global warming potential of the embodied GHG emissions from the electricity generation technologies. The uncertainty in the availability of renewable resources is modelled using the method of moments. A design procedure for building sustainable HES has been presented and the sensitivity analysis is conducted for determining the optimal solution set. [ABSTRACT FROM AUTHOR]

The share of the renewable energy sources (RES) in the global electricity market is substantially increasing as a result of the commitment of many countries to increase the contribution of the RES to their energy mix. However, the integration of RES in the electricity grid increases the complexity of the grid management due to the variability and the intermittent nature of these energy sources. Energy storage solutions such as batteries offer either short-term storage that is not sufficient or longer period storage that is significantly expensive. This paper introduces an energy management approach which can be applied in the case of power and desalinated water generation. The approach is based on mathematical optimization model which accounts for random variations in demands and energy supply. The approach allows using desalination plants as a deferrable load to mitigate for the variability of the renewable energy supply and water and/or electricity demands. A mathematical linear programming model is developed to show the applicability of this idea and its effectiveness in reducing the impact of the uncertainty in the environment. The model is solved for the real world case of Saudi Arabia. The optimal solution accounts for random variations in the renewable energy supply and water and/or electricity demands while minimizing the total costs for generating water and power. [ABSTRACT FROM AUTHOR]

Abstract: The utilisation of renewable energy resources for power generation is extremely important for Ireland due to the lack of indigenous fossil fuel resources. A micro-wind turbine is by far the most commonly used grid-connected micro-renewable electricity generation system for domestic applications in Ireland, followed by solar PV. Unfortunately, neither a single micro-wind turbine nor a single solar PV system can provide a continuous power supply due to variations in weather and climate conditions. The coupling of these two systems however can improve the power supply reliability by using the complementary characteristics of wind and solar energy. In this paper, a micro-renewable electricity-generation-system integration technique, tailored for applications in Ireland but generally applicable, is presented. Net present value is the parameter used to identify the optimal system. The optimal system can be a mono system, formed from a single micro-wind turbine or a single solar PV system, or a hybrid system formed from a combination of both. A renewable energy requirement is a constraint used in the integration to eliminate systems that cannot provide sufficient energy from renewable energy resources. The integration technique is applied to find the optimal system, under current Irish conditions, that can be formed from six sample micro-wind turbines and/or solar PV systems assembled from three sample solar PV modules. The analyses show that, with a 50% renewable energy requirement, the optimal system is a mono system containing a 2.4 kW micro-wind turbine; however, critically, the system is not economically viable. Four parameter studies assessing the effect of household electrical load, imported electricity price, exported electricity tariff and wind speed have also been conducted. From these studies it is seen that the most effective way to improve the financial performance of all systems is to offer a higher exported electricity tariff; installing a mono/hybrid system containing a micro-wind turbine in a location with a good wind resource can also have a significant effect. [Copyright &y& Elsevier]

Abstract: Currently, around 90% of Malaysia's electricity generation depends on fossil fuels. This reliance, in a long run, is not a secure option. However, renewable energy sources can contribute to a sustainable electricity generation system; but diversifying fuel supply chain is a complex process. Therefore, the aim of this paper is two folds. Firstly, various renewable resources potential are reviewed, and secondly an assessment model is developed for prioritizing renewable options. Four major resources, hydropower, solar, wind, biomass (including biogas and municipal solid waste) are considered. Their electricity generation potential, along with any likely shortcoming is also discussed. Moreover, using a multi-perspective approach based on analytic hierarchy process (AHP), an assessment model is developed. AHP model employs four main criteria, technical, economical, social and environmental aspects, and twelve sub-criteria. From the review it was found that renewable resources seem to have a sufficient potential to develop a sustainable electricity system. Furthermore, AHP model prioritize those resources, revealing that solar is the most favorable resource followed by biomass. Hydropower and wind however, are ranked third and fourth, respectively. The model also shows that each resource is inclined towards a particular criterion; solar towards economical, biomass towards social, hydropower towards technical, and wind towards environmental aspect. Besides reporting AHP model for the first time in Malaysian context, the assessment performed in this study, can serve decision makers to formulate long-term energy policy aiming for sustainability. [Copyright &y& Elsevier]

Abstract: In this research paper the effect of introducing financial incentives to promote green electricity generation, in Jordan, was studied. The incentives investigated include tax reduction, introduction of a grace period, provision of capital or reduced discount rate, reduced depreciation life of assets, and the usage of accelerated depreciation methods. The obtained results show that implementing such tools leads to positive financial improvements that serve in encouraging private sector to invest in renewable energy technologies. It is revealed that variations of both grace period and taxation rate lead to minor impacts on internal rate of return and net present value for such projects. On the other hand, the increase in depreciation period makes electricity generated from renewable sources more attractive, in terms of unit price of generated electricity, using the straight line depreciation method. In the contrary, the choice of accelerated depreciation method leads to better attractiveness as the depreciation period is reduced. The effect of discount rate variations is noticeable, and affects economics of such systems significantly. Finally, the results confirmed that wind energy is ranked first, followed by PV and concentrated solar power schemes are the last under the studied conditions in Jordan. [Copyright &y& Elsevier]

Abstract: The time-varying demand and stochastic power generation from renewable distributed generating resources necessitate an exhaustive assessment of distribution feeder parameters for the purpose of long-term planning. This paper proposes a novel formulation of probabilistic load flow for distribution feeders with high penetration of renewable distributed generation. The dependency between the load demand of different consumer classes and generation from different types of renewable resources is addressed in this study. In order to capture the coincidental variations of demand and generation, associated time series data for the same time instances are used. A transformation matrix based probabilistic load flow is formulated using the method of cumulants. Moreover, Pearson distribution functions are used to estimate the probability distribution of the line flows. The proposed load flow method is tested on a practical distribution feeder with high penetration of solar photovoltaic and wind energy conversion systems. The results demonstrate the aptitude of the proposed method for conducting probabilistic load flow studies with dependent non-Gaussian distribution of load and generation. [Copyright &y& Elsevier]

Abstract: This study investigates the possibility of using and developing hydrokinetic power to supply reliable, affordable and sustainable electricity to rural, remote and isolated loads in rural South Africa where reasonable water resource is available. Simulations are performed using the Hybrid Optimization Model for Electric Renewable (HOMER) and the results are compared to those from other supply options such as standalone Photovoltaic system (PV), wind, diesel generator (DG) and grid extension. Finally the paper points out some major challenges that are facing the development of this technology in South Africa. [Copyright &y& Elsevier]

Abstract: Tidal energy has the potential to play a key role in meeting renewable energy targets set out by the United Kingdom (UK) government and devolved administrations. Attention has been drawn to this resource as a number of locations with high tidal current velocity have recently been leased by the Crown Estate for commercial development. Although tides are periodic and predictable, there are times when the current velocity is too low for any power generation. However, it has been proposed that a portfolio of diverse sites located around the UK will deliver a firm aggregate output due to the relative phasing of the tidal signal around the coast. This paper analyses whether firm tidal power is feasible with ‘first generation’ tidal current generators suitable for relatively shallow water, high velocity sites. This is achieved through development of realistic scenarios of tidal current energy industry development. These scenarios incorporate constraints relating to assessment of the economically harvestable resource, tidal technology potential and the practical limits to energy extraction dictated by environmental response and spatial availability of resource. The final scenario is capable of generating 17 TWh/year with an effective installed capacity of 7.8 GW, at an average capacity factor of 29.9% from 7 major locations. However, it is concluded that there is insufficient diversity between sites suitable for first generation tidal current energy schemes for a portfolio approach to deliver firm power generation. [Copyright &y& Elsevier]

Abstract: In the last decade, Turkish electricity demand has increased more than 8% per annum as a result of economic development. Being one of the renewable energy sources par excellence, non-exhaustible, non-polluting and economically more attractive than other renewable sources, hydropower has turned out to be an important contributor to the future energy mix of the country. Turkey''s renewable energy sources especially hydropower sources are plentiful and extensive, and represent the second-largest domestic energy sources after coal. Turkey has a total gross hydropower potential of 433 TWh/year and 140 TWh/year of this capacity can be used economically. Currently, Turkey has 172 hydroelectric power plants in operation with total installed capacity of 13,700 MW generating an average of 48,000 GWh/year, which is 35% of the economically viable hydroelectric potential. 148 hydroelectric power plants are under construction 8,600 MW of installed capacity to generate average annual 20,000 GWh representing 14% of the economically viable potential. The share of renewables in total electricity generation is 17%, while that of thermal is 80% in 2009. The projection for the period 2010–2020 is for annual growth of 8% in total electricity generation. The additional generation capacity needed up to 2020 will require huge investments. This paper deals with present situation and future prospect of renewable energy and the role of hydropower in Turkey. [Copyright &y& Elsevier]

Abstract: Generating electricity, from renewable energy sources has become a high priority in the energy policy strategies at a national level as well as on a global scale. Although Turkey has many energy resources only coal and hydropower are significant at present, and as demand had risen, it has been necessary to import fuels to meet the total energy demand. The fossil resources, both indigenous and imported, have become expensive and also have undesirably high emissions. Turkey has an extensive shoreline and mountains and is rich in renewable energy potential. The share of renewables on total electricity generation is 35% while that of thermal power is 65% for the year 2010. Turkey is one of those countries that are considered rich and abundant in renewable energy resources. Turkey is facing serious challenges in satisfying its growing energy demand. To fuel a rapidly growing economy, the country’s electricity consumption is increasing by an average of 8–9% every year, and significant investments are needed in generation, transmission and distribution facilities to balance the power system’s supply and demand. With very limited oil and gas reserves, Turkey is increasingly turning to renewable energy sources as a means to improve its energy security and curb dependence on imported gas from Russia and Iran. This paper investigates the potential of renewable energy resources in Turkey at present and the magnitude of their present and future contributions to the national energy consumption. Energy politics are also considered. [Copyright &y& Elsevier]

Abstract: Lesotho’s energy balance is largely dominated by combustible renewable resources. However, the country is well endowed with hydropower resources for the development of both large and small-scale hydropower projects. There are several challenges that have to be addressed in order to reap the full benefits of this resource. Some of the main challenges are high capital investment costs on projects of this nature and heavy siltation of small reservoirs due to extensive soil erosion. Various studies countrywide have identified 22 sites, with a combined potential of more than 20 MW to be suitable for small hydropower development. Of these sites, 4 have been developed to operational from mid 1980’s to early 1990’s. The plants were designed as hybrid system with diesel generator sets. Three of those plants operate on a river run-off system. It has been a general practice that the plants run on diesel for most periods of the year, which render them more expensive to run. Currently, 2 of the plants are mothballed as a result of the costs and other operational problems frequently encountered. This paper gives an overview of the setbacks that inhibit the smooth operation of small hydropower plants in Lesotho. [Copyright &y& Elsevier]

Abstract: An experimental system was developed and tested in order to investigate the energetic performance of a solar photovoltaic system (PV) assisted earth-to-air heat exchanger (underground air tunnel) that is used for greenhouse cooling at the Solar Energy Institute, Ege University, Izmir, Turkey. Average value of temperature differences between inlet and outlet of earth-to-air heat exchanger (EAHE) was observed 8.29 °C at experimental measurements. The average heat discharge rate (cooling load) was realized as 5.02 kW by using 0.7 kW fan. System was operated about 11 h/day. As a result, total electricity energy consumption of the system was measured to be 8.10 kWh and 34.55% of this energy demand was provided from photovoltaic cells. Furthermore, 65.45% of the electricity energy demand was provided from grid connection. Results are discussed and interpreted in the paper for various performance metrics. [Copyright &y& Elsevier]

Abstract: The wind is a clean, abundant and entirely renewable source of energy. Large wind farms are being built around the world as a cleaner way to generate electricity, but operators are still searching for more efficient wind farm layouts to maximize wind energy capture. This paper presents an ant colony algorithm for maximizing the expected energy output. The algorithm considers wake loss, which can be calculated based on wind turbine locations, and wind direction. The proposed model is illustrated with three different scenarios of the wind speed and its direction distribution of the windy site and, comparing to evolutionary strategy algorithm available in literature. The results show that the ant colony algorithm performs better than existing strategy, in terms of maximum values of expected energy output and wake loss. [Copyright &y& Elsevier]

Abstract: The west and south coastal region of Korea has very strong tidal current speeds and therefore accommodates many suitable sites for the application of TCP (Tidal Current Power). The maximum current speed recorded in the south is up to 6.5 m/s. Unlike other renewable energy sources, TCP is an extremely reliable, predictable and continuous energy source as the current pattern and speed can be predicted throughout the year. One of the essential components in a TCP device is the rotor converting the inflow current into the rotational energy. The design optimization of the rotor is very important to maximize the power production. The performance of the rotor can be determined by various parameters including the number of blades, shape, sectional size, hub, diameters etc. The blade of the rotor is one of the essential components which can convert tidal current energy into rotational energy to generate electricity. The variable blade properties determine the performance, efficiency and stability of the turbine system. This paper presents the design procedure for a 300 kW tidal current turbine blade. The HAT turbine model was designed based on the wind mill turbine design principles together with known turbine theories. To verify the compatibility of the turbine design method and to analyze the properties of design factors, the 3D CFD model was applied with the ANSYS CFX program. The characteristics and performances of the blades can be applied in the design of 300 KW and larger capacity TCP rotors. [Copyright &y& Elsevier]

Abstract: Anaerobic digestion applied to the organic waste produced in urban environments could provide a critical solution to growing garbage problems while simultaneously reducing external energy requirements. As landfills across Canada and the rest of the world are filled to their limits, a carbon-neutral process which can locally generate electricity and heat while providing up to 50% volatile solid reduction is something to be seriously considered. This paper investigates the feasibility of urban anaerobic digestion, presents four techniques for biogas estimation – ultimate analysis, yield from molecular formula analysis, a novel computer simulation technique using Anaerobic Digestion Model #1 (ADM1), and a literature review of experimentally determined biogas yields. In addition, a case study for small-scale anaerobic digestion system design is presented for an urban building. [Copyright &y& Elsevier]

Abstract: Jammu and Kashmir the northern most state of India is blessed with immense potential for utilization of renewable energy. The state at present is fairly untapped in terms of energy utilization and thus venturing into this region would definitely prove to be profitable. The natural energy sources like sunshine, wind, vegetation, water flow, biomass and other biological wastes though abundantly available in the state yet are not being potentially harnessed resulting in very low per capita energy availability, deforestation and poor health. Renewable energy acquires a promising option not only for energy availability next view and of environment protection but also the socio-economic conditions of the people residing in these areas can be improved to a great extent. The hydroelectric power has tremendous potential for generation of electricity in the state because the topography of the state provides extensive network of canals and streams. This paper describes the resource potential and opportunity to enter the market and bring more renewable energy projects in the form of solar, biomass derived fuels, biogas and hydroelectric in the state. [Copyright &y& Elsevier]

Abstract: China is facing a number of energy-related challenges such as the shortage of electricity supply and environmental pollution. Renewable energy is encouraged and will play more important role in the power generation components of China. As a renewable energy, biomass power has a rapid growth in the past decade in China. In line with this development, the biomass power industry faces opportunities for development as well as challenges. Using SWOT analysis method, this paper reviews and assesses the factors of strengths, weaknesses, opportunities, and threats of biomass power generation industry of China. Data used in the analysis stem from multiple sources including statistical reports, literature, regulations, policies, and case studies. These findings not only help to understand the status quo of the industry, but also provide valuable information to master the future development and potential risks of the industry in China. [Copyright &y& Elsevier]

Abstract: This paper presents the work performed within ADIRA project funded by European Union as a consortium of many countries to boost the integration of desalination units with renewable energy in rural areas. The work focused on the study of Water desalination by Reverse Osmosis (RO) and electricity generation using Photovoltaic Technology (PV) with additional battery storage. RO-PV system has been successfully designed, installed and tested in Hartha Charitable Society in northern part of Jordan as part of the ADIRA project. The system is composed of PV panels (433 Wp), softener and compact RO unit with typical daily water production of 500 L. The system produced clean drinking water from a salty water feed with salt content up to 1700 mg/L. The technical details of the RO plant, the energy supply and the operation strategies of the system are presented in this study. The effect of meteorological data like solar insolation, ambient temperature, daily sunshine hours on the performance of the RO-PV system are studied. Furthermore, effect of operating pressure and temperature on recovery percentage, salt rejection and specific energy consumption in addition to details about the PV current and voltage are also discussed. [Copyright &y& Elsevier]

Abstract: The potential for a 10 MW photovoltaic power plant in Abu Dhabi is examined in this paper using RETScreen modeling software to predict energy production, financial feasibility and GHG emissions reductions. Initial results show high energy production potential, generating 24 GWh and saving over 10,000 tons of GHG emissions annually, but poor financial prospects yielding a net present value (NPV) of −$51 million. Benefits of reducing GHG and air pollution emissions by replacing natural gas with PV generation are calculated to have a net present value of $47 million, with a large range of possible values. Results show that the high initial costs and low expected price for electricity generated are driving reasons why photovoltaic systems are not being implemented in Abu Dhabi. A feed-in tariff rate of $0.16/kWh is recommended to make large-scale PV systems profitable. [ABSTRACT FROM AUTHOR]

Abstract: Renewable energy sources (RES) are mainly used in the electrical sector. Electricity is not a storable commodity. Hence it is necessary to produce the requested quantity and distribute it through the system in such a way as to ensure that electricity supply and demand are always evenly balanced. This constraint is actually the main problem related to the penetration of new renewables (wind and photovoltaic power) in the context of complex energy systems. Moreover the design of optimal energy resource mixes in climate change mitigation actions is a challenge faced in many places. The paper analyzes the problem of new renewable energy sources penetration. The case of Italian scenario is considered as a meaningful reference due to the characteristic size and the complexity of the same. The various energy scenarios are evaluated with the aid of a multipurpose software taking into account the interconnections between the different energetic uses. In particular it is shown how the penetration of new renewable energy sources is limited at an upper level by technological considerations and it will be more sustainable if an integration of the various energy uses (thermal, mobility and electrical) will be considered. A series of optimized scenarios are developed. In each case the maximum RES penetration feasible with the constraints was defined. Then analysis is applied to an energy system model of Italy showing how an integrated development of CHP and electric mobility can aid a further integration of wind and photovoltaic energy power. Finally the primary energy consumption saving possible in case of consistent penetration of intermittent renewables and CHP was identified. [ABSTRACT FROM AUTHOR]

Abstract: China is facing a number of energy-related challenges such as shortage of electricity supply and environmental pollution. The Government recognized the important role the renewable energy plays in the power generation structure. As a result, a series of supporting policies, laws and regulations have been issued to boost the renewable energies in China. This paper provides a critical analysis of the policy framework for the renewable energy in China and its impacts on the power generation structure. The relevant policy documents, including the most recent government work report delivered by Premier Wen Jia-bao during the Third Session of the 11th National People’s Congress (NPC) in March 2010 are analyzed. The patterns of renewable energy developments are found strongly correlated with the promulgation of relevant policies. [Copyright &y& Elsevier]

Abstract: This paper analyses the field performance of different off-grid generation technologies applied to the electrification of rural villages. Autonomous diesel generators are the most extended technology. It is a well known application, although it has also some disadvantages: fuel transportation and consumption costs, maintenance needs or environmental problems. In places where accessibility is difficult and costly, the use of local energy resources (basically renewable) constitutes a significant advantage. Due to the intermittent character of those resources, renewable generation systems are sometimes associated to diesel gen-sets in order to increase the reliability of supply of small and medium-size communities. A comparative analysis between diesel, hydro-diesel and photovoltaic-diesel technologies is presented in this article. It is based on data collected from systems installed in the rural area of the province of Jujuy, northwest of Argentina. The study covers from year 2001 to 2008, with a research universe of 16 locations supplied by thermal diesel generation (1 with a large-diesel system and other 15 with smaller ones), 5 locations with hydro-diesel and 7 with photovoltaic-diesel systems. The energy demand evolution of rural villages is also studied because of its influence on the system operation and sustainability. [Copyright &y& Elsevier]

Abstract: This paper presents a Mixed Integer Linear Programming (MILP) model that was developed for the optimal planning of electricity generation schemes for a nation to meet a specified CO2 emission target. The model was developed and implemented in General Algebraic Modeling System (GAMS) for the fleet of electricity generation in Peninsular Malaysia. In order to reduce the CO2 emissions by 50% from current CO2 emission level, the optimizer selected a scheme which includes Integrated Gasification Combined Cycle (IGCC), Natural Gas Combined Cycle (NGCC), nuclear and biomass from landfill gas and palm oil residues. It was predicted that Malaysia has potential to generate up to nine percent of electricity from renewable energy (RE) based on the available sources of RE in Malaysia. [Copyright &y& Elsevier]

Abstract: This paper presents the pico-hydro development status in Lao PDR and introduces the Pump as Turbine (PAT) concept as an alternative for isolated communities (40–500 people). The intention is to provide a long-term reproducible system for communities where pico-hydro propeller turbines are insufficient and proper turbines are expensive. This approach presents a high quality and cost-effective solution for rural electrification which can be installed, commissioned, and maintained by local staff and villagers. Furthermore, a 2kWel PAT-scheme is proposed for a community in the Xiagnabouli province and considers power generation alternatives, sizing, asynchronous motor simulation, civil works, cost estimation, and social aspects. [Copyright &y& Elsevier]

Abstract: Sources of renewable energies (for example landfill gas, wind, solar energy) are environmentally friendly and electric power generation in South Korea has concentrated on new and renewable energy technologies. The purpose of this paper is to study the economic and environmental influence of renewable energies on existing electricity generation market of South Korea with energy-economic model called ‘Long-range Energy Alternative Planning system’ and the associated ‘Technology and Environmental Database’. Business as usual scenario was based on energy supply planning with existing power plant. And then, the alternative scenarios were considered, namely the base case with existing electricity facilities, the installation plan of different renewable energy facilities, technological improvement and process dispatch rule according to merit order change. In each alternative scenario analysis, alternation trend of existing electricity generation facilities is analyzed and the cost of installed renewable energy plants and CO2 reduction potential was assessed quantitatively. [Copyright &y& Elsevier]

Abstract: This paper describes the design of two different specific speed microhydro turbines operating at heads between 6 and 12m, at small scale and up to heads of 50m at larger scales. The features are specifically tailored for ease of manufacture and uniquely resistant to debris blockage. Test machines are described and test results given; hydraulic efficiencies of over 70% have been achieved in all test models despite the fact that the turbine blades are made from flat plate, specifically to simplify manufacture. Outline drawings are given with key dimensions for each reference model, along with the equations for scaling to arbitrary sizes. These turbines are the mixed- and radial-flow members of a family of turbines developed to cover the microhydro range from 2 to about 50m of head, which is below the range where Pelton wheels are applicable. [Copyright &y& Elsevier]

The economics of renewable energy are the largest barrier to renewable penetration. Nevertheless, the strong desire to reduce environmental emissions is considered a great support for renewable energy sources. In this paper, a full analysis for the cost of the kWh of electricity generated from different systems actually used in Egypt is presented. Also renewable energy systems are proposed and their costs are analyzed. The analysis considers the external cost of emissions from different generating systems. A proposed large scale PV plant of 3.3 MW, and a wind farm 11.25 MW grid connected at different sites are investigated. A life cycle cost analysis for each system was performed using the present value criterion. The comparison results showed that wind energy generation has the lowest cost, followed by a combined cycle–natural gas fired system. A photovoltaic system still uses comparatively expensive technology for electricity generation; even when external costs are considered the capital cost of photovoltaic needs to be reduced by about 60% in order to be economically competitive. [Copyright &y& Elsevier]