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Abstract The advantage of accurate forecasts is that it solves the main problem related to renewable energies: their variability. Indeed, while renewable energies has not yet replaced fossil fuels, in spite of the efforts of many governments, it is because of their intermittent nature, hence the importance of prediction in this field. The new approach for energy prediction that we propose in this paper, is founded on the analysis of the dynamical behavior of the photovoltaic production of the Faculty of Sciences and Technology of Beni Mellal, Morocco. It consists in performing the phase space reconstruction, which allowed us later to build a database for the input of the neural network and thus take into account the dynamics of the system in the forecasting process. Then, in search of more precision, we introduce the wavelet transformation, to simplify the database constructed from phase space reconstruction. Finally, comparing between the predictions and the actual observations confirmed the efficiency of our approach. Highlights • PV production forecast has an major role in its integration into electricity mix and thus in the fight against climate change. • In this work, we propose a new approach for forecasting, based on the exploitation of the phase space reconstruction. • The proposed model is a hybrid method combining the phase space reconstruction, DWT method and recurrent neural network. • The method is tested on real observations to confirm the efficiency of our approach. • Comparison between predictions and actual data confirmed the effectiveness of our approach given the improved results. [ABSTRACT FROM AUTHOR]

Abstract In order to mitigate climate change and reduce fossil fuel dependency in Iran, the government of the country has announced its renewable energy policies to increase the use of renewable energies, but the share of the energy generation mix of Iran is very low due to the lack of public acceptance. These challenges continue and can be hard to overcome at all levels. This paper investigates this problem at regional level by measuring public acceptance towards development of climate-friendly technologies in order to provide required feedbacks to policy-makers of the government for ushering changes in their policies already made or in their executing mechanism, possibly deducting future risks such as public opposition from their end and improving the level of acceptance. This study uses a mixed-methods analytical approach for quantitatively taking that level, including creativity techniques and fuzzy cognitive maps (FCMs). FCMs could directly map out policy-makers' cognitions on the problem. This study provides the mathematical formulation of the problem with its conceptual interpretation to import policy-makers' knowledge into FCMs when the knowledge is gained explicitly with creativity techniques. The authors focused on a case of Solar Water Heater adoption in the city of Behbahan in Khuzestan Province. Graphical abstract Image Highlights • A combinative method for measuring public acceptance of clean energy technologies is proposed. • It provides the mathematical formulation of the acceptance problem with its conceptual interpretation. • It focused on a case study of solar water heater adoption in Iran. [ABSTRACT FROM AUTHOR]

Abstract Desalinated water is an alternative and feasible water source that can help solve water scarcity problems. However, most desalination plants are operated using fossil fuels, which contribute to greenhouse gas (GHG) emissions. To face the problem of climate change, many countries are developing policies that promote renewable energy for electricity production. These policies might impact desalination costs. This paper proposes a methodology to evaluate the economics of desalination by integrating investment costs, operational and maintenance costs, and GHG emissions costs. This method will enable us to determine the impact of renewable energy polices on desalination costs. The empirical application was developed for Chile, a country with a promising future in renewable energy, and revealed that the full costs of desalinated water decrease by approximately 22% when the current electricity production mix is changed to predominantly renewable energy production. Moreover, this application illustrated the relevance of adopting a carbon tax to motivate the switch to renewable energy. This study demonstrates that the adoption of renewable energy policies involves a notable synergy with water issues. Highlights • Methodological proposal to estimate desalination costs integrating external costs. • Evaluation of the impact of renewable energy polices on desalination costs. • The adoption of renewable energy policies involves synergy with water issues. [ABSTRACT FROM AUTHOR]

Abstract High elevation or high latitude hydropower production (HP) strongly relies on water resources that are influenced by glacier melt and are thus highly sensitive to climate warming. Despite of the wide-spread glacier retreat since the development of HP infrastructure in the 20th century, little quantitative information is available about the role of glacier mass loss for HP. In this paper, we provide the first regional quantification for the share of Alpine hydropower production that directly relies on the waters released by glacier mass loss, i.e. on the depletion of long-term ice storage that cannot be replenished by precipitation in the coming decades. Based on the case of Switzerland (which produces over 50% of its electricity from hydropower), we show that since 1980, 3.0%–4.0% (1.0–1.4 TWh yr−1) of the country-scale hydropower production was directly provided by the net glacier mass loss and that this share is likely to reduce substantially by 2040–2060. For the period 2070–2090, a production reduction of about 1.0 TWh yr−1 is anticipated. The highlighted strong regional differences, both in terms of HP share from glacier mass loss and in terms of timing of production decline, emphasize the need for similar analyses in other Alpine or high latitude regions. Graphical abstract Image 1 Highlights • First quantification of Alpine hydropower production share from glacier mass loss. • Since 1980, 1.0 to 1.4 TWh yr-1 of Swiss hydropower comes from glacier mass loss. • Expected country-scale production reduction by 2070–2090 of 1.0 TWh yr-1. • Notable regional differences despite of continuous retreat of all Swiss glaciers. [ABSTRACT FROM AUTHOR]

Renewable energy generation through biorefineries is increasingly considered as more sustainable in comparison with fossil-based fuels as well as single-product renewable energy systems. However, biorefineries have many system variations, and therefore, the evaluation of their environmental performance and comparison with conventional systems before large-scale deployment is essential. In this paper, the sustainability of three different biorefiney scenarios (Sc-1, Sc-2, and Sc-3) based on Eruca sativa ( ES ) as feedstock were investigated using a life cycle assessment approach from energy balance and environmental point of views. Biodiesel, electricity, ethanol, heat, glycerol, and/or biomethane were the marketable products taken into account under the conditions of these scenarios. According to the results obtained, we argue that although biorefineries offer unique features as most effective alternatives for mitigating climate change and reducing dependence on fossil fuels, the selection of biomass processing options and management decisions can widely affect the final evaluation results. Overall, providing transportation fuel through Sc-2 in which biodiesel, electricity, ethanol, heat, and glycerol were produced could decrease GHG emissions by approximately 140% compared with the combustion of neat diesel while also offering a total net energy gain (NEG) of 4.94E+08 MJ/yr. Nevertheless, if biorefineries are to be used for future transportation fuel production, a great deal of efforts should still be made to achieve better environmental performance in the Human Health and Ecosystem quality damage categories. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze the factors determining the choice of energy policy setting in favor of renewable energy sources. We investigate if such determinants are different between countries at different stage of development. Finally, we study if the adoption of green energy policies is characterized by complementary or substitution effects. Our analysis aims at responding at two research questions: what are the factors influencing a country's choice for a specific type of energy policy? Is it possible to identify either complementary or substitute policy interventions based on a country's level of economic development? Moreover, are developing systematically different from developed countries in manage public and private resources for renewable energies? The empirical analysis employs a panel probit model estimated over a sample of 56 countries observed between 2004 and 2011. The results show that while context variables have the same impact in developed and developing countries, public operational variables play a different role. Governments in richer countries are bound to play only a role of an arbiter. On the contrary, governments of developing countries are more directly involved in the management of energy policies. Hence, a greater impact is recognized to policies with direct involvement of the government. [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: Nowadays, conventional coal or gas fired power plants are the dominant way to generate electricity in the world. In recent years there is a growth in the field of renewable energy sources in order to avoid the threat of climate change from fossil fuel combustion. Solar energy, as an environmental friendly energy source, may be the answer to the reduction of global CO2 emissions. This paper presents the concept of Solar Aided Power Generation (SAPG), a combination of renewable and conventional energy sources technologies. The operation of the 300 MW lignite fired power plant of Ptolemais integrated with a solar field of parabolic trough collectors was simulated using TRNSYS software in both power boosting and fuel saving modes. The power plant performance, power output variation, fuel consumption and CO2 emissions were calculated. Furthermore, an economic analysis was carried out for both power boosting and fuel saving modes of operation and optimum solar contribution was estimated. [Copyright &y& Elsevier]

Abstract: The outcome of COP15, the conference on climate change in Copenhagen, was the Copenhagen Accord which was recognised by the 193 countries that attended. The Accord set no compulsory limits on carbon emissions, and none of the countries that introduced it – USA, China, India [with Brazil and South Africa] – has signed the Annexe to the Kyoto Agreement, committing them to limit their emissions. Climate change is only of secondary importance to them compared with eradicating poverty. Nevertheless three of these countries are in the lead currently for installing renewables, far ahead of most of those [only 37 out of 187 countries world-wide] who are committed to limiting their emissions. This paper explains why. The main function of renewable energy is to save fuel, thereby reducing energy imports and maintaining security of energy supplies without the need to fight world wars over them. Also, being capital intensive with all the money paid up-front, renewables avoid the price fluctuations that bedevil the oil and other fossil fuel industries. As capacity is doubling every 3 years, renewables prices will come down with savings of scale, so wind power in particular will soon be the cheapest form of power. [Copyright &y& Elsevier]