Paper Title, Authors, Abstract (Issue 1, Volume 4, 2010)

Pages

The Analysis of the Adsorption Cooling Subsystem used in a MCCHP System with Stirling Engine like Prime Mover
V. Popa, C. Popa, A. Serban, L. Costiuc

Abstract: The paper presents an analysis of the cooling subsystem used in a trigeneration system with Stirling engine like prime mover. The advantages and disadvantages of the adsorption cooling are presented, related to absorption cooling system. The schematic thermal diagram of the trigeneration system is presented. Because the low efficiency of the Stirling engine, a thermally activated cooling subsystem is used. A theoretical thermodynamic analysis of the adsorption cooling system is presented. The influence of the operating conditions on performance of the adsorption cooling is presented.
 

Evaluation of Power System Transient Stability and Definition of the Basic Criterion
Z. Eleschova, M. Smitkova, A. Belan

Abstract: Power system stability is defined as an ability of the power system to reestablish the initial steady state or come into the new steady state after any variation of the system’s operation value or after system/s breakdown. The stability and reliability of the electric power system is highly actual topic nowadays, especially in the light of recent accidents like splitting of UCTE system and north-American blackouts. This paper deals with the potential of the evaluation in term of transient stability of the electric power system within the defense plan and the definition of the basic criterion for the transient stability – Critical Clearing Time (CCT).
 

    Paper Title, Authors, Abstract (Issue 2, Volume 4, 2010)

Pages

Employing Solid Urban Waste in an IIR-SOFC in Cogenerative Arrangement
Orlando Corigliano, Gaetano Florio, Petronilla Fragiacomo

Abstract: In the context of searching for energy and environmentally sustainable systems, fuel cells seem to be an appropriate technology. In particular, those operating at high temperature, possessing the great advantage of flexibility of fuel feeding, can be powered by a gas derived from biological sources. In fact, by treating the organic fraction of solid urban waste in an anaerobic environment, a biofuel, consisting mainly of methane and carbon dioxide, may be produced. In this paper, the combination of an anaerobic digester with a high temperature solid oxide fuel cell (SOFC) system in a cogenerative arrangement is proposed. The biomass processed involves the provision of biogas feeding the SOFC system. The latter, owing to its high thermal potential, can be arranged with an indirect internal system of fuel conversion into hydrogen that, in contrast to the direct one, reduces the problems of anode carbon deposits. A technical analysis, to evaluate performances of the integrated system, specifically in relation to the carbon dioxide concentration in the feeding gas, is performed, by using some energy and environmental indexes typical of cogeneration plants. In this article, in order to test the proposed project, an application to a real case has been made, in which, the biogas plant is designed starting from the organic waste from canteens in the Calabria region. The bio-fuel fed to the SOFC system involves the combined generation of heat and power with which to meet energy needs, estimated by energy audit users.
 

Selection of the Most Appropriate Regions for Wood Fuel based Cogeneration Plants using Multi-Criteria Decision Analysis Methods
A. Volkova, E. Latosov, A. Siirde

Abstract: Multi-criteria decision analysis is used both for location problems and for energy problems. For successful involving of wood-fired cogeneration in Estonia it is important to define the most appropriate region, where the wood-fuel cogeneration plants can be located. The method used for defining the optimal location is based on the multi-criteria decision analysis (MCDA), which includes the Delphi method for criteria selection, the Analytic Hierarchy Process (AHP) method as weighting method and the elementary weighted sum method (WSM) for the final decision defining. In the result the most appropriate county in Estonia for wood-fuel based cogeneration plant installation was defined.
 

    Paper Title, Authors, Abstract (Issue 3, Volume 4, 2010)

Pages

Carbon Capture and Storage: Cost Analysis of Electricity Production for Latvia
Julija Gusca, Irina Naroznova, Dagnija Blumberga, Anna Volkova

Abstract: Carbon capture and storage (CCS) is a significant technology in the limitation of greenhouse gases in the atmosphere worldwide. A carbon capture and storage system consists of four general processes: carbon capture, carbon compression and transport, carbon injection, and carbon storage. Implementation of carbon capture and storage technologies with the aim to minimise carbon dioxide emissions in the atmosphere might influence the national energy sector both from an economic and environmental point of view. This paper provides the methodology for the evaluation of cost scenarios of natural gas, coal and biomass power plants with different capture technologies used - post combustion monoethanolamine (MEA) solvent capture, chemical - looping capture, pre-combustion monoethanolamine (MEA) solvent capture and pre-combustion methyldiethanolamine (MDEA) capture. The results of the paper show the CO2 reduction potential from 2015 to 2020 and present the factors affecting the cost of electricity related to the introduction of CCS in Latvia.
 

Cost Benefit Analysis of Passive Houses and Low-Energy Houses Compared to Standard Houses
A. Audenaert, S.H. De Cleyn

Abstract: As the energy demand used for space heating accounts for 78% of EU15 household delivered energy consumption significant reductions in energy demand can be achieved by promoting low energy buildings. Energy efficiency in buildings has become a key goal of any energy policy. Europe relies on the Energy Performance of Buildings Directive (EPBD), which has been converted by Flanders into the ‘Energy Performance and Interior Climate’ (EPB). Taking into account this Flemish EPB-standard (in terms of maximum U-values, E-level and K-value), Our study investigates three building types: the standard house, the low-energy house and the passive house. As more far-reaching measures concerning energy savings usually lead to higher investments, the aim of our study is to perform an economic analysis in order to determine the economic viability of the three building types.
 

    Paper Title, Authors, Abstract (Issue 4, Volume 4, 2010)

Pages

Effect of Organic Loading Rate on Biohydrogen Production from Sweet Sorghum Syrup by Anaerobic Mixed Cultures in Anaerobic Sequencing Batch Reactor
P. Saraphirom, A. Reungsang

Abstract: This study reported the effect of 4 organic loading rates (OLR) varied from 25-40 g hexose/L-d on bio-hydrogen production from sweet sorghum syrup by anaerobic mixed cultures in anaerobic sequencing batch reactor. The optimum OLR was found to be 30 g hexose/L-d in which a maximum yield, a maximum specific hydrogen production rate and a hydrogen content of 0.53 mol H2/mol hexose, 32.52 mL/g MLVSS.d and 37.66%, respectively, were achieved. Microbial community analyzed by DGGE at the optimum OLR of 30 g hexose/L-d indicated that the predominance hydrogen producer was Clostridium acetobutylicum, C. proteolyticum and Clostridium sp. A low hydrogen yield obtained might be resulted from the presence of Lactococcus lactis and Lactobacillus sp. in the fermentation broth.
 

The Modeling of Calculations of Thermodynamic and Electronic Parameters of Hot Electrons in a Quantum Well
M. A. Mehrabova

Abstract: The heating of charge carriers in a quantum well was studied. The calculations of thermodynamic and electronic parameters: concentration, energy, chemical potential, heat-capacity and thermo electromotive force of hot two-dimensional electron gas in a quantum well in the energy region near or below the threshold for emission of optical phonon under the assumption that below this threshold an electron temperature can be defined, had been modeled. The obtained equations describe the dependence of heat-capacity and thermal electromotive force on a film thickness and an electron temperature in a good manner. It was determined that the acquired results calculated for the model under consideration, strongly differed from the results calculated on the base of a Maxwell distribution function.