Renewable Energy Technologies

Efficient electric power transmission is a major concern in Nigeria. Electric power transmission is the link between power generation and power distribution network. The performance evaluation of the 132KV Sub-transmission lines is a research work carried out to ascertain the status of the networks for better performance. The data used in the research work were obtained from the Transmission Company of Nigeria (TCN) substations and the networks under consideration constitute five generating stations which are Afam 4 & 5, Afam 6 (Shell), Omoku, Trans-Amadi and Independent Power Project (IPP) at Afam. The 132KV networks of the Port-Harcourt Sub-region under analysis constitute 9 numbers of 132KV active networks and 8 numbers of 33KV active networks and the total active loads connected to the 33KV buses were 443.617MVA. Electrical Transient Analyzer Program (ETAP 12.6) was used to model the network and to perform simulation using Newton-Raphson techniques to solve the static load flow problems and to obtain the real and reactive power flow; determine the various bus voltages, and to investigate the power losses in the networks. During simulation, it was found that the majority of the network's apparatus such as transformers, buses, transmission lines and generators were overloaded beyond their capacities. From the results of the base-case simulation, two capacitor banks (60Mvar and 90MVar) were introduced to enhance the voltage margin and 160MWof power was added to the networks to provide adequate power supply to reduce the total power loss from (10.540MW +j 28.119MVar) to (3.8170MW+j0.8616MVar) thereby improving the performance of the networks.

Biomass pyrolysis is a promising renewable sustainable source of fuels and petrochemical substitutes. It may help in compensating the progressive consumption of fossil-fuel reserves. The present article outlines biomass pyrolysis. Various types of biomass used for pyrolysis are encompassed, e.g., wood, agricultural residues, sewage. Categories of pyrolysis are outlined, e.g., flash, fast, and slow. Emphasis is laid on current and future trends in biomass pyrolysis, e.g., microwave pyrolysis, solar pyrolysis, plasma pyrolysis, hydrogen production via biomass pyrolysis, co-pyrolysis of biomass with synthetic polymers and sewage, selective preparation of high-valued chemicals, pyrolysis of exotic biomass (coffee grounds and cotton shells), comparison between algal and terrestrial biomass pyrolysis. Specific future prospects are investigated, e.g., preparation of supercapacitor biochar materials by one-pot one-step pyrolysis of biomass with other ingredients, and fabricating metallic catalysts embedded on biochar for removal of environmental contaminants. The authors predict that combining solar pyrolysis with hydrogen production would be the eco-friendliest and most energetically feasible process in the future. Since hydrogen is an ideal clean fuel, this process may share in limiting climate changes due to CO 2 emissions.
Keywords Sustainable and renewable energy source; Fossil-fuel alternatives; Biomass pyrolysis; Biofuel (bio-oil, biogas, biochar); Charcoal (activated carbon); Hydrogen fuel

The Kingdom of Saudi Arabia has launched ambitious plans to integrate alternative energy sources into the national grid, including 25 GW of concentrated solar thermal power (CSP). There are several options available for the design of a CSP plant, including collection technologies, solar thermal receivers, heat transfer fluids, and energy storage capacities. In this study, a techno-economic analysis has been conducted, considering the strengths, weaknesses, opportunities, and threats (SWOT) for each technology in order to build a common understanding and vision. The analysis outcomes were incorporated with the Saudi energy sector requirements and local weather conditions to define alternative scenarios. Six power plant scenarios were defined for performance and financial evaluation. This includes parabolic trough, solar tower, and linear Fresnel collection technologies. A simulation was subsequently carried out through the System Advisor Model (SAM). The alternative scenarios were assessed through defining weather, technical, and financial parameters. Satellite observations and field measured data were combined to obtain a typical meteorological year weather data for the capital city Riyadh. The SWOT analysis revealed that the parabolic trough collectors are the most mature and that they are adopted in a majority of operational CSP projects, which is a key factor at the early stages of CSP integration in Saudi Arabia. Solar towers are gaining popularity owing to their ability to incorporate high levels of energy storage. The simulation results depicted significant capacity factors per initial cost as well as annual energy for solar tower scenarios. The linear Fresnel technique is in its infancy for large-scale operations, yet the results showed a high potential, including the lowest levelized cost of energy compared to other scenarios. The findings of this research will help assess alternatives for CSP projects with consideration of all relevant criteria.

Following requirements of the Energy Policy Act of 2005, most U.S. states require utility companies to adopt interconnection and net metering policies, allowing customers to become prosumers who both consume and produce electricity, generating electricity using distributed renewable energy technologies, connecting to the existing electric utility grid, and receiving compensation for excess electricity generation. This paper reviews existing interconnection and net metering policies instituted by investor owned utilities (IOUs) across the U.S., specifically focused on policies regulating small scale, residential or Tier 1 (a term used to indicate policies applicable to smaller scale rather than larger scale, although the size at which DG systems are classified as either Tier 1 or higher tiers varies by utility) installations. Publicly available data from each IOU reveal inconsistencies in interconnection and net metering policies, within states and even within individual companies. In addition, accurate information is often unavailable to consumers. Perhaps most importantly, results suggest that compensation for excess distributed generation is often obscured in utility policy. The results of this study provide important insight into interconnection and net metering policies for distributed renewable energy generation, as states and utilities continue to modify interconnection and net metering policies in response to increased adoption of distributed renewable energy systems.

Introducción
El aumento de la frecuencia y la intensidad de fenómenos climáticos —correlato del calentamiento global y en parte producto de los centenares de miles de toneladas de gases invernadero (GEI) arrojados diariamente a la atmósfera—, constituye una de las consecuencias más negativas de la matriz energética prevaleciente en el nivel global, fuertemente basada en combustibles fósiles. La cantidad actual de emisiones se aproxima al nivel establecido, de modo tal que dicho fenómeno no supere los dos grados centígrados, nivel considerado límite para hacer manejable el clima del planeta.El transporte automotor aporta una fracción importante de las
emisiones de CO2 —alrededor de un 14 %— (Herzog, 2009). Posee
una importante responsabilidad en el calentamiento global. Ello acarrea severos cuestionamientos al paradigma tecnológico de la locomoción basado en la combustión interna, induciendo el desarrollo de sistemas alternativos de generación, almacenamiento y uso de la energía.
El acelerado desarrollo en tecnologías de baterías, en especial de litio, de nuevos materiales como el grafeno y de la impulsión eléctrica, están transformando varios sistemas tecnológicos vinculados a este sector. Emergen nuevas industrias que tendrán impactos socioeconómicos considerables que podrán modificar la matriz energética. Estas tecnologías presentan algunas ventajas importantes respecto a las existentes.Entre ellas, se destaca ser más eficientes en el uso de la energía y menos contaminantes.

The present study aims to investigate the thermal and catalytic pyrolysis of CD case wastes over natural zeolite catalyst. The effect of temperature and catalyst on product yields have been investigated for each condition. The thermal pyrolysis experiments were carried out at the reactor temperature of 400, 450, and 500°C. Furthermore, the effect of natural zeolite (NZ) catalyst on pyrolysis products was also studied at various catalyst to feedstock ratio. The results showed that the temperature and catalyst affected the products yield and liquid composition. CD case pyrolysis produced highest liquid fraction at the temperature of 450°C. Furthermore an estimated 5.74 kW of electricity can be generated by pyrolysis oil produced from CD case wastes at a recycling site in Yogyakarta city, Indonesia.

A sustainable transition is premised upon moving from a carbon energy regime to a renewable energy regime; a highly contested political-economic transformation, to say the least. In places like the United States and European Union the main form of renewable energy is bioenergy, especially biofuels. Recent policy and industry efforts are focusing on the development and implementation of what are known as ‘drop-in’ biofuels, so named because they can be incorporated into existing distribution infrastructure (e.g. pipelines) and conversion devices with relatively few, if any, technical modifications. As with carbon energy, bioenergy has particular materialities that are implicated in the political-economic possibilities and constraints facing societies around the world. These political materialities of bioenergy shape and are shaped by new energy regimes and therefore problematize the notion of a drop-in biofuel. Thus further examination of the political materialities of bioenergy, and of renewable energy more generally, is of critical importance for successful sustainable transitions.

Short-term wind power forecasts are fundamental information for the safe and economic integration of wind farms into an electric power system. In this work we present a Generalized Additive Model to predict the wind power quantiles (Quantile Regression) from which we obtain a prediction of the wind power production probability density function in a wind farm. The methodology was implemented in the VENTOS Program. In order to illustrate the application of the methodology as well as the VENTOS Program this work presents the results achieved by a computational experiment based on real data from a wind farm located in Galicia, Spain.

The aim of this study was to develop a model of ocean wave energy converter based on water mass gravity force (WEC-WGF) to overcome the flaws of existing wave energy converter that rely on water buoyancy force. This paper presented physical model experiment result of wave energy converter based on water mass gravity force. The harvested energy were compared with calculated theoretical energy based on linear wave theory. The physical model investigation was carried out at wave simulator (flume) in Hydraulics Laboratory Department of Civil Engineering, Hasanuddin University Indonesia on February-March 2016. The physical model consists of a series of one-way gear connected with plastic container as an interface between converter and regular generated wave. Investigation was carried out to observe the influence of gravity weight mass and wave height variations on converters harvested power. The experiment result indicated that the amount of converter Power Take Off (PTO) were strongly influenced by variation of gravity weight mass (M gw), followed by wave height (H) and wave period (T) respectively. These results outperform the calculated power by means of linear wave theory. The result of this experiment could be used as a reference to develop theoretical or analytical model of wave energy converter based on water mass gravity force. Keywords— Wave, Gravity Force, Renewable Energy, Wave Energy Converter I. INTRODUCTION Energy, water and food are essential needs to support the continuation of human activities. In the last few decades, the main source of energy depends on the burning of fossil fuel. Since the depletion of oil resources, most countries in the world started to realize the importance of environmental conservation and efficient use of fossil fuel reserves. Moreover, the reduction of fossil fuel as a main source of energy hopefully could reduce the level of CO2 emissions which are considered as a main source of global air pollution. The total global CO2 emissions in 2013, comprised of; power plants contribute 42%, transportation 23%, industrial activities 19%, households 6%, services and other sectors produced 3% to 7%. The amount of CO2 released into the atmosphere in the last 42 years increased by approximately 230% from 13.995 million tons in 1971 increased to 32.190 million tons in 2013 [1] [2]. Efforts to reduce CO2 emissions has been carried out through the utilization of renewable energy sources such as wind energy (wind), hydropower plants, solar power, ocean currents and wave energies. In term of energy density, wave energy poses the greatest energy content that is available for 24 hours. However it has not been fully utilize due to the cost per kWh did not economically feasible due to the flaws of existing wave energy converter technologies [3].

The feasibility of several new technologies for energy efficiency in buildings is investigated by means of a novel in-house developed Building Energy Performance Simulation (BEPS) code (called DETECt). A novel case study referred to a nonresidential NZEB to be built up in Naples is presented.

This study aims to examine the potential substitute natural gas (SNG) production by integrating black liquor gasification (BLG) island with a small wheat straw-based non-wood pulp mills (NPM), which do not employ the black liquor recovery cycle. For such integration, it is important to first build knowledge on expected improvements
in an overall integrated non-wood pulp mill energy system using the key performance indicators. O2-blown circulating fluidized bed (CFB) gasification with direct causticization is integrated with a reference small NPM to evaluate the overall performance. A detailed economic analysis is performed together with a sensitivity analysis based on variations in the rate of return due to varying biomass price, total capital investment, and natural gas prices. The quantitive results showed considerable SNG production but significantly reduced electricity
production. There is a substantial CO2 abatement potential combining CO2 capture and CO2 mitigation from SNG use replacing compressed natural gas (CNG) or gasoline. The economic performance through sensitivity analysis reflects significant dependency on both substitute natural gas production and natural gas market price. Furthermore, the solutions to address the challenges and barriers for the successful commercial implementation of BLG based polygeneration system at small NPMs are discussed. The system performance and discussion on the real application of integrated system presented in this article form a vital literature source for future use by large number of small non-wood pulp industries.

Renewable energy sources are those that replenish naturally without depletion. Examples of such sources are bioenergy, hydropower, geothermal, wind and solar energy sources. The alarming rate of global energy demand and consumption necessitates an immediate solution for energy conservation and maximum efficiency of new technological gadgets now being built. As a gadget, a solar water heater transforms dc electricity into heat energy, which is then transferred to the water in which it is immersed. The size of the heater is determined by its design, capacity, and intended purpose; it might be for household or industrial use. As an alternative to conventional electric water heaters, this effort focuses on the design and development of a solar-powered smart water heater. In tests using a variety of settings, the solar-powered smart heater that was constructed performed admirably. The components used include a PIC16F876A microcontroller, a 12 V/300 W monocrystalline PV, a 12 V/ 40 A charge controller, and 12 V / 150 W dc submersible heating element among others. The temperature control capacity of the fabrication makes it useful in water management system applications such as in aquaculture fingerling hatchery, hot water dispenser and shower among others. The system showed excellent performance in water temperature control using a 150 watts dc heater.