The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
More than 1.3 billion people lack access to grid electricity. Uganda provides a typical example of an under-electrified country, with less than 12% of Ugandans having access. To address the lack of electricity access, there has been much analysis devoted to grid-connected distributed generation. What these analyses lack is a consideration that even where grid electricity reaches people, it is not...
Performance of a HRES (hybrid renewable energy system) is highly affected by changes in renewable resources and therefore interruptions of electricity supply may happen in such systems. In this paper, a method to determine the optimal size of HRES components is proposed, considering uncertainties in renewable resources. The method is based on CCP (chance-constrained programming) to handle the uncertainties...
In this paper, flash evaporation and thermal vapor compression are used to reduce heat consumption of CO 2 capture processes and two improved capture systems are proposed. One is the flash evaporator (FE) and thermal vapor compressor (TVC)-aided system, the other is the heated flash evaporator (HFE) and thermal vapor compressor (TVC)-aided system. Analyses are carried out to verify their effectiveness...
Europe has a significant target ahead to fulfill: to achieve the goal of nearly zero energy buildings from the year 2021. This paper presents viable scenarios to achieve the achievement of nearly zero energy dwellings in the southern European country of Cyprus. The analysis is based on the documentation of the developments in the building sector after the adoption of mandatory building insulation...
In the present study, the thermal decomposition behavior of three common biowastes in Taiwan (cedar sawdust, coffee bean residue, and rice straw) upon fast pyrolysis was studied. Products were determined by gas chromatography–mass spectrometry. The composition of the resulting bio-oils was also quantified. TGA (thermogravimetric analysis) results indicate that thermal degradation of the biowaste samples...
In this study, a combined test of the WGS (water–gas shift) reactor and a Pd-based composite membrane was carried out for pre-combustion CO 2 capture in a coal gasifier. The two series of WGS reactions, i.e., a high-temperature shift and a low-temperature shift, were performed under a gas composition of 60% CO and 40% H 2 at 2100 kPa to imitate coal gasification. The CO 2 enrichment...
Wheat is the second most important cereal crop in Bangladesh and production is highly sensitive to variations in the environment. We estimate productivity and energy efficiency of wheat farming in Bangladesh by applying a stochastic production frontier approach while accounting for the environmental constraints affecting production. Wheat farming is energy efficient with a net energy balance of 20,596 MJ...
The aim of this work is to develop stoichiometric equilibrium models that permit the study of parameters effect in the gasification process of a particular feedstock. In total four models were tested in order to determine the syngas composition. One of these four models, called M2, was based on the theoretical equilibrium constants modified by two correction factors determined using published experimental...
A multi-cell model based on a prototypical, IP-SOFC (integrated-planar solid oxide fuel cell) stack design was constructed in this study to perform comprehensive thermal stress analyses and to calculate the probability of survival. The temperature profiles generated by a thermo-electrochemical model were applied to calculate the thermal stress distributions in a multiple-cell module. The effect of...
This study deals with fabrication, physico–chemical characterizations and thermal properties of n-octadecane nanocapsules as organic PCM (phase change materials) for TES (thermal energy storage). Nano-encapsulated organic PCM was fabricated by encapsulation of n-octadecane as a core with St (styrene) – MMA (methylmethacrylate) copolymer shell using miniemulsion in-situ polymerization method. The influence...
This work investigates the effect of temperature and bed material on the yields and composition of gas and tar produced from gasification of two types of biomass feedstock previously torrefied at 275 °C. Special attention was devoted to the evolution of tar composition under the different experimental conditions. Experiments were conducted in a fluidized bed reactor using two different types of bed...
Expanded graphite was investigated as a material for flow-field plates in PEFCs (polymer electrolyte fuel cells). Because expanded graphite is flexible but has similar material properties with normal graphite, channels on flow-field plates were designed to have single channel in order to compare operational characteristics including diffusion of reactants through ribs by comparing polarization curves...
This paper presents a novel application of a sensible TES (thermal energy storage) system for simultaneous energy conservation and water desalination in power plants. First, the TES mitigates negative effects of high ambient temperatures on the performance of ACC (air-cooled condenser) that cools a 500 MW CCPP (combined cycle power plant); next, the same TES satisfies the cooling requirements in a...
The rotatable design was applied for directing pyrolysis experiment of palm bark with the variation of retention time and reaction temperature. Based on the regression equations, the optimal operating conditions were extrapolated at 13.2 min, 459 °C and 15.7 min, 475 °C. The gas product comprised mainly C 1 –C 4 hydrocarbons with the content up to 58.2 wt% while the liquid product...
The interconnection between a renewable power generation facility and a power grid poses challenges because of volatility and intermittent characteristics. Energy storage is one of the best solutions for this problem. This paper presents an integrated energy storage system (ESS) based on hydrogen storage, and hydrogen–oxygen combined cycle, wherein energy efficiency in the range of 49%–55% can be...
This two-part paper investigates the potential of ORC (organic Rankine cycles) for the exploitation of low-medium enthalpy geothermal brines. Part A deals with thermodynamic analysis and optimization, while Part B focuses on economic optimization.In ORC field the wide range of available working fluids and cycle configuration entails a non-univocal selection of fluid and cycle parameters for the exploitation...
Knowledge of the electricity demand for different electrical appliances in households is very important in the work to reduce electricity use in households. Metering of end-uses is expensive and time consuming and therefore other methods for calculation of end-use electricity can be very useful. This paper presents a method to calculate the electricity used for lighting in households based on regression...
Combustion of pulverized coal in oxy-combustion technology is one of the effective ways to reduce the emission of greenhouse gases into the atmosphere. The process of transition from conventional combustion in air to the oxy-combustion technology, however, requires a thorough investigations of the phenomena occurring during the combustion process, that can be greatly supported by numerical modeling...
Thermochemical storage with moist air is a promising way to achieve seasonal storage of solar heat. This paper investigates the link between outlet and inlet airflow conditions in the case of hydration/dehydration of thermochemical processes operating with moist air at atmospheric pressure. A thermodynamic analysis of a solid/gas reactor operating in open mode is performed. That leads to a thermodynamic...
Since 2007, gross domestic product (GDP) growth in China's inland provinces has exceeded that of the affluent coastal provinces. Concurrently, they have also been given more lenient energy intensity reduction targets to provide latitude for continued growth. The regional unevenness of economic development and energy policy has implications for the ability of the country to achieve its energy savings...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.