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Abstract The use of renewable energy resources, especially wind power, is receiving strong attention from governments and private institutions, since it is considered one of the best and most competitive alternative energy sources in the current energy transition that many countries around the world are adopting. Wind power also plays an important role by reducing greenhouse gas emissions and thus attenuating global warming. Another contribution of wind power generation is that it allows countries to diversify their energy mix, which is especially important in countries where hydropower is a large component. The expansion of wind power generation requires a robust understanding of its variability and thus how to reduce uncertainties associated with wind power output. Technical approaches such as simulation and forecasting provide better information to support the decision-making process. This paper provides an overview of how the analysis of wind speed/energy has evolved over the last 30 years for decision-making processes. For this, we employed an innovative and reproducible literature review approach called Systematic Literature Network Analysis (SLNA). The SLNA was performed considering 145 selected articles from peer-reviewed journals and through them it was possible to identify the most representative approaches and future trends. Through this analysis, we identified that in the past 10 years, studies have focused on the use of Measure-Correlate-Predict (MCP) models, first using linear models and then improving them by applying density or kernel functions, as well as studies with alternative techniques, like neural networks or other hybrid models. An important finding is that most of the methods aim to assess wind power generation potential of target sites, and, in recent years the most used approaches are MCP and artificial neural network methods. Graphical abstract Image 1005 Highlights • This paper provides an overview of how the analysis of wind energy has evolved over the last years. • We employed an innovative and reproducible literature review approach called Systematic Literature Network Analysis. • From 145 articles was possible to identify the most representative approaches and future trends. • Developing countries will reach the same level of investment in the field of wind energy. [ABSTRACT FROM AUTHOR]

This paper aims to relate total greenhouse gas emissions footprint with Energy Return on Energy Invested for Coal, Natural Gas, Hydro, Geothermal, Wind and Solar PV electricity generation methods. Emissions from construction, decommissioning, operations and maintenance, and fuel, are all included in the analysis. Often the generation equipment is imported so much of the emissions associated with construction are “virtual” emissions (i.e. imported). These virtual emissions contribute to a peak emission as renewable generation is installed at the start to ultimately lead to a lower emissions factor for a countries’ electricity system over time. The peak occurs due to the short-term emissions resulting from construction and a long-term emissions reduction due to the low/zero carbon renewable generation installed. The electricity sector in New Zealand is used as a case study for projected new generation through to 2050 for four scenarios (a) Global Low Carbon, (b) Mixed Renewables, (c) High Grid and (d) High Solar. The study demonstrates that as total greenhouse gas footprints are included an emissions peak occurs due to new construction, mainly because of renewable generation, especially solar and high energy emissions factors in countries manufacturing generation equipment. [ABSTRACT FROM AUTHOR]

Despite the positive momentum achieved by the renewable energy sector in recent years, there are substantial challenges that need the attention of the global community, and one of the more pressing issues is dealing with the deleterious external costs of power generation. One of the parameters to compare costs of energy across various technologies is levelised cost of energy (LCOE), but it has been conventional practice to neglect the external costs in estimating the LCOE of power generation technologies. Furthermore, as LCOE is a critical indicator for policy and decision makers, there is a need to juxtapose actual costs of renewable and conventional power generation technologies. This research paper attempts to internalise some of these external and GHG emission costs across various power generation and storage technologies in all the G20 countries, as they account for 85% of global power consumption. As future investment decisions are largely influenced by costs, estimates in this research prove renewables and storage to be far cheaper than fossil and nuclear sources by 2030, even without considering external costs. The myth that renewables are ‘way too expensive’ has been debunked repeatedly, and the cost decline of wind and solar photovoltaic (PV) technologies have outpaced most industry expectations. The results of this research not only substantiate this trend, but also statistically display that all the G20 countries have the opportunity to decrease their energy costs significantly, between now and 2030. Renewable energy technologies offer the lowest LCOE ranges across G20 countries in 2030. Utility-scale solar PV generally shows the lowest values ranging from 16 to 117 €/MWh el and onshore wind LCOE range is from 16 to 90 €/MWh el . Rooftop solar PV generally offers the next lowest LCOE ranging from 31 to 126 €/MWh el , followed by LCOE of offshore wind power ranging from 64 to 135 €/MWh el . Solar PV and battery systems are highly competitive on an LCOE basis at utility-scale ranging from 21 to 165 €/MWh el and at residential scale from 40 to 204 €/MWh el . The G20, as well as other countries, can continue to develop their economies in a sustainable manner, along with substantial co-benefits in adjacent policy fields such as higher national welfare, better health of citizens, lower respective health costs and improved energy security. [ABSTRACT FROM AUTHOR]

Abstract: Many different technologies have been growing under the umbrella of Smart Grids, which can be split into three major blocks: generation, transmission, and distribution. Generation and transmission have been evolving and improving as they have been under the control of utility companies, but distribution has been lagging behind on some of these improvements, due to the number of stakeholders involved in the process. With the integration of information and communication technology into the electricity distribution, there has been a spike in research and other studies to prepare for the future. In this paper, we analyzed all papers related to the topics of Smart Grids and Distribution. Because of the novelty of the concept, the results validate the expectation of an empirical approach in papers using case studies to simulate or conduct pilot runs of the technologies before their massive implementations. Strategies are mostly driven by the USA, while other countries are focusing on quality improvements of the already strategized initiatives with an efficiency-related goal in mind. Consumer participation is going to play a key role in the near future as it requires developing a new business model with the inclusion of self-generation and selling-back of excess capacity to the utility company. [Copyright &y& Elsevier]

A central strategy for climate change mitigation is expanding electricity generation from renewable energy sources, with an increasing share of decentralized generation. Some of these sources are variable renewable energy (VRE) sources, such as wind and solar resources. Measures have to be enacted to integrate VRE into an existing power supply system. One approach is switching from grid electricity supply towards direct demand of VRE generation to reduce grid transportation requirements and variable electricity grid feed-in. Within this context, energy flexibility control of manufacturing systems can be used to match energy demand of manufacturing systems with on-site VRE generation. Nonetheless, due to their inherent dynamic behavior, interlinked manufacturing systems provide additional operational and technical challenges such as maintaining throughput when energy control actions are executed. Further, stochastic influences from, for example, VRE generation and manufacturing system behavior constitute the requirement for a real-time approach on the level of manufacturing execution systems. Consequently, this paper presents a method for real-time control of manufacturing systems with several processes and intermediate buffers to increase utilization of (on-site) generated VRE without compromising system throughput. An initial method for an energy flexibility control logic is presented and a simulation prototype to evaluate its effectiveness is implemented. A case study is used to demonstrate the effectiveness and to test sensitivities to system parameter changes. Impact on direct VRE demand and additional operational indicators is evaluated. [ABSTRACT FROM AUTHOR]

Policies to assure combatting climate change and realising energy security have stimulated a rapid growth in global installed capacity of renewable energy generation. The expansion of power generation from renewables, though, has so far lagged behind the growth in generation capacity. This indicates missed and relatively cheap opportunities to reduce GHG emissions. This paper sheds light on the mismatch between installed capacity and power generation for the case of wind power. It analyses and compares wind power developments in the four countries that contributed most to the increase in wind power capacity during the last decade: namely, China, the United States, Germany and Spain. We estimate the dynamics of capacity utilisation of wind power installations and identify its drivers. Finally, we identify potential policies to reduce the gap between power capacity and generation, which will contribute to cost-effective reduction of GHG emissions. [ABSTRACT FROM AUTHOR]

Micro-hydropower (MHP) presents new opportunities to generate electricity from within existing water infrastructure. This paper quantifies the environmental impacts of electricity generation from three MHP case studies (15–140 kW) in the water industry, using a life cycle assessment approach. Environmental burdens were calculated per kWh electricity generated over nominal turbine operational lifespans. Compared with marginal UK grid electricity generation in combined cycle turbine natural gas power plants, normalised life cycle environmental burdens for MHP electricity were reduced by: >99% for global warming potential (GWP); >98% for fossil resource depletion potential; >93% for acidification potential; 50–62% for human toxicity potential. However, the burden for abiotic resource depletion potential was 251–353% higher for MHP than marginal grid-electricity. Different quantities of raw materials and installation practices led to a range in GWP burdens from 2.14 to 4.36 g CO 2 eq./kWh. One case benefitted from very low site preparation requirements while others required substantial excavation works and material quantities. Carbon payback times ranged from 0.16 to 0.31 years, extending to 0.19–0.40 years for worst-case scenarios examined as part of a sensitivity analysis. The carbon payback period for future MHP installations was estimated to increase by 1% annually, as the carbon intensity of marginal grid electricity is predicted to decline. This study demonstrates that MHP installations in the water industry have a strongly positive environmental balance. [ABSTRACT FROM AUTHOR]

Worldwide, the majority of small islands not connected to the main grid is still dependent on fossil fuels. From an economic and environmental point of view, this condition is no more sustainable given the high costs for electricity generation and the high level of pollutant emissions. Furthermore, the dependence on fossil fuel represents a risk for the security of the supply of several small developing Countries since they are obliged to import those resources from foreign Countries. The introduction of renewable energy sources in small islands represents a valid solution to solve these problems. In this context, the paper investigates the case of Lampedusa, a small Italian island whose electrical power system is currently totally supplied by diesel power plants. In the paper, the authors investigate the transition toward an economically and technically feasible generating system based on solar, wind and sea wave plants, to achieve specific targets of decarbonization. Commercial technologies are adopted for the exploitation of solar and wind sources, while sea wave plants are based on an innovative device, currently under development at the University of Palermo. A mathematical model is proposed to find the optimal energy mix that can satisfy a fixed share of annual electricity production from renewables, considering the Levelized Cost of Electricity. Finally, the proposed solution is analyzed in order to check the dynamic stability of the power system. The paper shows that, for replacing the 40% of the current electricity demand of Lampedusa, an optimal energy mix comprising 1509 kW from photovoltaic plants, 2100 kW from wind turbines and 640 kW from wave energy converters is needed. In this way, the actualized cost for the electricity production could be reduced to 0.260 €/kWh from the current value of 0.282 €/kWh. • The paper investigates the energy sector in a small island in the Mediterranean Sea. • The case study reveals a strong energy dependence on fossil fuels. • Economic feasibility of a renewable energy mix is proved. • LCOE is introduced as criterium to size the energy mix. • Grid stability is analyzed in case of a small grid with a high share of renewables. [ABSTRACT FROM AUTHOR]

Abstract: This paper examines the major minerals producing countries and the potential that local energy mix and renewable energy resources have for lowering the impact of the industry, with respect to carbon dioxide emissions. Furthermore, it seeks to estimate the potential for new technologies, energy efficiency and demand-side measures to reduce emissions. Of total carbon dioxide emissions, 71% arise from fossil fuels used in thermal applications and 29% from indirect electricity generation. We find the highest theoretical potential for reduction of emissions from thermal applications is from the increased use of renewable biofuels and charcoal instead of fossil fuels (up to 46% of total industry net emissions), while conversion of various applications to use renewable hydrogen may reduce emissions by 28%. Electricity generation emissions could be “substantially reduced” by switching to electricity generation from cleaner sources, with hydropower a key potential contributor (reduction of 22% of total industry emissions). Solar thermal and electrical production may only be capable of 2–7% reduction in the industry''s emissions. [Copyright &y& Elsevier]

This paper assesses the potential energy and environmental impacts of an anaerobic digester coupled with a combined heat and power plant powered with bio-wastes from the agri-food sector. The analysis is carried out through the Life Cycle Assessment methodology following a "cradle-to-grave" approach and is based mostly on primary data. The anaerobic digester - combined heat and power plant is analysed considering a twofold perspective: one more energy – oriented where the main function of the system is to generate renewable electricity and a waste – oriented one in which the main function is treating bio-wastes. In addition, the environmental indirect effects related to potential competitive uses of bio-wastes are evaluated. Biomass transport and the electricity consumed during the operation phase make the largest contribution (higher than 60%) to almost all the impact categories examined. The comparison with the electricity eco-profile from the national grid and with a composting facility highlights that the anaerobic digester - combined heat and power system may reach better energy and environmental performances for both the electricity generation and bio-waste management. Image 1 • A life cycle assessment of an anaerobic digester coupled with a combined heat and power plant is performed. • The plant is analysed through the perspectives of energy production and waste treatment. • Biomass transport and electricity consumed during the operation phase make the largest impact contribution. • The examined system can be a sustainable solution for both electricity generation and bio-waste management. • Indirect effects in competitive economic sectors can offset the environmental benefits of the examined system. [ABSTRACT FROM AUTHOR]