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Over the past few years, there has been a growing global consensus related to the importance of renewable energy to minimize the emission of greenhouse gases. The solution is an increase in the number of renewable power plants but unfortunately, this leads to a high dependence on climate variables which are already affected by climate change. Brazil is one of the largest producers of electricity by renewables through its hydro-dominant power generation system. However, hydro-generation depends on water inflows that are directly affected by climate change that consequently affect the electricity production. Therefore, these changes need to be considered in the operation and planning of a hydro-dominant power system. In this paper, we present the effects of different climate scenarios in the water inflows produced by the regional Eta climate model. Normally, studies use an optimization model to make decisions in case of a hydro-thermal scheduling problem and use the assured energy to evaluate the hydro-production. In this analysis, water inflows used in the optimization process consider different trends according to its associated climate scenario. Our paper shows that climate change may drastically impact the system assured energy and consequently, the system's capability to supply load. [ABSTRACT FROM AUTHOR]

Abstract The paper analyses the possibility of application of PV/T systems in moderate climate conditions. Experimental part of research studies has been developed in Patras, Greece, in October–November. In that time climatic conditions in Greece are similar to summer (warmest) weather conditions in Poland. Some aspects of Polish climatic conditions, especially of solar radiation availability are presented. The liquid single glazed PV/T module has been selected for consideration as the most suitable for described climatic conditions. Experimental outdoor stand with such PV/T module has been designed and constructed to determine its energy performance. A mathematical model of the photovoltaic/thermal solar system operation is presented. Existing formula for determination of the PV/T temperature during its operation has been validated by experimental studies. As a result the correction - design factor has been introduced to the formula. It helps to take into account the design (number of covers) of the PV/T module, when its energy performance and operation are determined through simulation studies. Simulation studies of the dynamics of a microscale PV/T system supplying energy (electricity and heat to Domestic Hot Water system) to a standard single-family house has been performed using own numerical code. Selected results of simulation studies of the operation of different cases (sizes) of PV/T systems are described. Simulation studies of operation of the PV/T systems in micro scale application in high latitude countries show, that for 2 months of a year, in December and January, more electrical than thermal energy is generated by the PV/T system. In summer problems with too high temperature of the working fluid of the PV/T module can occur. As a result, the electrical efficiency decreases. In Polish climatic conditions a PV/T system should be provided with a continuous heat removal system to assure efficient operation of the system. Highlights • Among different types of PV/T modules the liquid single glazed type is the most recommended for high latitude countries. • The design of the PV/T module should be taken into account, when the PV effective temperature is calculated. • Correction factor in equation determining the PV effective temperature in the liquid glazed PV/T module has been formulated. • Problems with too high temperature of a working fluid of the PV/T module in summer in high latitude countries. • Higher electricity than thermal energy gains in PV/T system in winter in high latitude countries. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports the outcome of the project on “Capacity building in formulating harmonized policy instruments for the promotion of Renewable Energy and Energy Efficiency in the ASEAN member countries”. With the growing concerns about green house gas (GHG) emission and consequent climate change, renewable energy sources have become more attractive option for electricity generation around the world. Studies have been made on the status of renewable energy potential and utilization, major barriers in promoting renewable energy in ASEAN countries, major energy policies to overcome barriers, and existing renewable energy and energy efficiency policies in ASEAN countries. Paper concludes that ASEAN has not utilized its renewable energy resources anywhere near to the potential. Analysis found that the key factor that has to be amended is “policies and regulations in renewable energy and energy efficiency” at both country level and regional level. But, ASEAN is not yet ready for the full harmonization of the policies. However, it recommends that, with the project outputs it is possible to focus on the specific policy instruments common to most of the member countries, such that it could use to augment ASEAN Plan of Action for Energy Cooperation (APAEC) initiatives. [Copyright &y& Elsevier]

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]

Abstract: A case study of the development of an overall resource assessment for the Wave Hub site in the southwest UK is presented. Wave Hub is one of the earliest large-scale wave farms planned. Several resource assessment studies have been performed for the site, but the published results are high-level and predicted power availability varies significantly. This paper provides a detailed overview and re-analysis of the multiple datasets used in the original studies, which consisted of a combination of physical measurement and numerical modelling. The quality of the datasets is assessed, and reasons for the discrepancies between predicted resource levels investigated. Results from a SWAN model for the region illustrate significant levels of spatial variability in the resource due to the complexity of the local bathymetry, and examination of long-term global model datasets shows notable inter-annual variability. It is thus concluded that a resource assessment methodology utilising datasets from multiple locations and of short duration significantly reduces the accuracy of the predicted levels of resource. From these results, key learnings for future developments are discussed. [Copyright &y& Elsevier]

Abstract: Due to the various seasonal, monthly and daily changes in meteorological data, it is relatively difficult to find a suitable model for Photovoltaic power supply (PVPS) system. This paper deals with the modelling and simulation of a PVPS system using an Adaptive Neuro-Fuzzy Inference Scheme (ANFIS) and the proposition of a new expert configuration PVPS system. For the modelling of the PVPS system, it is required to find suitable models for its different components (ANFIS PV generator, ANFIS battery and ANFIS regulator) that could give satisfactory results under variable climatic conditions in order to test its performance and reliability. A database of measured climate data (global radiation, temperature and humidity) and electrical data (photovoltaic, battery and regulator voltage and current) of a PVPS system installed in Tahifet (south of Algeria) has been recorded for the period from 1992 to 1997. These data have been used for the modelling and simulation of the PVPS system. The results indicated that the reliability and the accuracy of the simulated system are excellent and the correlation coefficient between measured values and those estimated by the ANFIS gave a good prediction accuracy of 98%. Additionally, test results show that the ANFIS performed better than the Artificial Neural Network (ANN), which has also being tried to model the system. In addition, a new configuration of an expert PVPS system is proposed in this work. The predicted electrical data by the ANFIS model can be used for several applications in PV systems. [Copyright &y& Elsevier]

Abstract: The use of renewable energy has a long history. Biomass, for instance, has been used for heating and cooking, while wind has been used in the irrigation of fields and to drive windmills for centuries. Although Turkey has many energy resources, all of these with the exception of coal and hydropower, cannot meet the total energy demand. Turkey has been importing resources to meet this deficit. These resources have become increasingly expensive and also have undesirably high emissions ratings. Turkey has an extensive shoreline and mountains and is rich in renewable energy potential. The share of renewables on total electricity generation is 29.63% while that of natural gas is 45% for the year 2006. The projection prepared for the period between 2006 and 2020 aims an annual growth of 8% for the total electricity generation. According to this projection, it is expected that renewables will have a share about 23.68% with a decrease of 5.95% while natural gas will have a share about 33.38% for 2020. This paper presents the present state of world renewable energy sources and then looks in detail at the potential resources available in Turkey. Energy politics are also considered. [Copyright &y& Elsevier]