Abstract: The draw solute separation process in Forward
Osmosis desalination was simulated in Aspen Plus chemical process
modeling software, to estimate the energy consumption and compare
it with other desalination processes, mainly the Reverse Osmosis
process which is currently most prevalent. The electrolytic chemistry
for the system was retrieved using the Elec – NRTL property method
in the Aspen Plus database. Electrical equivalent of energy required
in the Forward Osmosis desalination technique was estimated and
compared with the prevalent desalination techniques.
Abstract: To simulate heating systems in buildings, a research oriented computer code has been developed in Sharif University of Technology in Iran where the climate, existing heating equipment in buildings, consumer behavior and their interactions are considered for simulating energy consumption in conventional systems such as heaters, radiators and fan-coils. In order to validate the computer code, the available data of five buildings was used and the computed consumed energy was compared with the estimated energy extracted from monthly bills. The initial heating system was replaced by the alternative system and the effect of this change was observed on the energy consumption. As a result, the effect of changing heating equipment on energy consumption was investigated in different climates. Changing heater to radiator renders energy conservation up to 50% in all climates and changing radiator to fan-coil decreases energy consumption in climates with cold and dry winter.
Abstract: The continued growth of the cities is causing an
increase of the amount of surface to illuminate. However, this rise
into lighting brings some unintended consequences such as increased
of energy consumption or the light pollution. To make these effects
less intrusive as possible some councils have chosen to perform a
part-night lighting in some areas. Nonetheless, this kind of shutdown
may cause serious problems which we intend to highlight in this
paper.
Abstract: Vernacular building is considered as sustainable in
energy consumption and environment and its thermal performance is
more and more concerned by researchers. This paper investigates the
thermal property of the vernacular building in Lhasa by theoretical
analysis on the aspects of building form, envelope and materials etc.
The values of thermal resistance and thermal capacity of the envelope
are calculated and compared with the current China building code and
modern building case. And it is concluded that Lhasa vernacular
building meets the current China building code of thermal standards
and have better performance in some aspects, which is achieved by
various passive means with close response to local climate conditions.
Abstract: Distillation column is one of the most common
operations in process industries and is while the most expensive unit
of the amount of energy consumption. Many ideas have been
presented in the related literature for optimizing energy consumption
in distillation columns. This paper studies the different heat
integration methods in a distillation column which separate Benzene,
Toluene, Xylene, and C9+. Three schemes of heat integration
including, indirect sequence (IQ), indirect sequence with forward
energy integration (IQF), and indirect sequence with backward
energy integration (IQB) has been studied in this paper. Using
shortcut method these heat integration schemes were simulated with
Aspen HYSYS software and compared with each other with
regarding economic considerations. The result shows that the energy
consumption has been reduced 33% in IQF and 28% in IQB in
comparison with IQ scheme. Also the economic result shows that the
total annual cost has been reduced 12% in IQF and 8% in IQB
regarding with IQ scheme. Therefore, the IQF scheme is most
economic than IQB and IQ scheme.
Abstract: In recent years, the research in wireless sensor
network has increased steadily, and many studies were focusing on
reducing energy consumption of sensor nodes to extend their lifetimes.
In this paper, the issue of energy consumption is investigated and two
adaptive mechanisms are proposed to extend the network lifetime.
This study uses high-energy-first scheme to determine cluster heads
for data transmission. Thus, energy consumption in each cluster is
balanced and network lifetime can be extended. In addition, this study
uses cluster merging and dynamic routing mechanisms to further
reduce energy consumption during data transmission. The simulation
results show that the proposed method can effectively extend the
lifetime of wireless sensor network, and it is suitable for different base
station locations.
Abstract: This paper presents an environmental and technoeconomic
evaluation of light duty vehicles in Iran. A comprehensive
well-to-wheel (WTW) analysis is applied to compare different
automotive fuel chains, conventional internal combustion engines and
innovative vehicle powertrains. The study examines the
competitiveness of 15 various pathways in terms of energy
efficiencies, GHG emissions, and levelized cost of different energy
carriers. The results indicate that electric vehicles including battery
electric vehicles (BEV), fuel cell vehicles (FCV) and plug-in hybrid
electric vehicles (PHEV) increase the WTW energy efficiency by
54%, 51% and 46%, respectively, compared to common internal
combustion engines powered by gasoline. On the other hand,
greenhouse gas (GHG) emissions per kilometer of FCV and BEV
would be 48% lower than that of gasoline engines. It is concluded
that BEV has the lowest total cost of energy consumption and
external cost of emission, followed by internal combustion engines
(ICE) fueled by CNG. Conventional internal combustion engines
fueled by gasoline, on the other hand, would have the highest costs.
Abstract: The quest for alternatefuels for a CI engine has
become all the more imperative considering its importance in the
economy of a nation and from the standpoint of preserving the environment. Reported in this paper are the combustion performance and P-θ characteristics of a CI engine operating on B20 biodiesel fuel derived from Jatropha oil.Itis observed that the twin effect of advancing the injection timing and increasing the injector opening pressure (IOP) up to 220 barhas resulted in minimum brake specific
energy consumption and higherpeak pressure. It is also observed that
the crank angle of occurrence of peak pressure progressestowards top
dead center (TDC) as the timing is advanced and IOP is increased.
Abstract: This study applies the sequential panel selection
method (SPSM) procedure proposed by Chortareas and Kapetanios
(2009) to investigate the time-series properties of energy
consumption in 50 US states from 1963 to 2009. SPSM involves the
classification of the entire panel into a group of stationary series and
a group of non-stationary series to identify how many and which
series in the panel are stationary processes. Empirical results obtained
through SPSM with the panel KSS unit root test developed by Ucar
and Omay (2009) combined with a Fourier function indicate that
energy consumption in all the 50 US states are stationary. The results
of this study have important policy implications for the 50 US states.
Abstract: The importance of low power consumption is widely
acknowledged due to the increasing use of portable devices, which
require minimizing the consumption of energy. Energy dissipation is
heavily dependent on the software used in the system. Applying
design patterns in object-oriented designs is a common practice
nowadays. In this paper we analyze six design patterns and explore
the effect of them on energy consumption and performance.
Abstract: To learn about China-s future energy demand, this paper first proposed GM(1,1) model group based on recursive solutions of parameters estimation, setting up a general solving-algorithm of the model group. This method avoided the problems occurred on the past researches that remodeling, loss of information and large amount of calculation. This paper established respectively all-data-GM(1,1), metabolic GM(1,1) and new information GM (1,1)model according to the historical data of energy consumption in China in the year 2005-2010 and the added data of 2011, then modeling, simulating and comparison of accuracies we got the optimal models and to predict. Results showed that the total energy demand of China will be 37.2221 billion tons of equivalent coal in 2012 and 39.7973 billion tons of equivalent coal in 2013, which are as the same as the overall planning of energy demand in The 12th Five-Year Plan.
Abstract: Using logarithmic mean Divisia decomposition technique, this paper analyzes the change in industrial energy intensity of Fujian Province in China, based on data sets of added value and energy consumption for 35 selected industrial sub-sectors from 1999 to 2009. The change in industrial energy intensity is decomposed into intensity effect and structure effect. Results show that the industrial energy intensity of Fujian Province has achieved a reduction of 51% over the past ten years. The structural change, a shift in the mix of industrial sub-sectors, made overwhelming contribution to the reduction. The impact of energy efficiency’s improvement was relatively small. However, the aggregate industrial energy intensity was very sensitive to both the changes in energy intensity and in production share of energy-intensive sub-sectors, such as production and supply of electric power, steam and hot water. Pathway to reduce industrial energy intensity for energy conservation in Fujian Province is proposed in the end.
Abstract: The power consumption of an Optical Packet Switch
equipped with SOA technology based Spanke switching fabric is
evaluated. Sophisticated analytical models are introduced to evaluate
the power consumption versus the offered traffic, the main
switch parameters, and the used device characteristics. The impact
of Amplifier Spontaneous Emission (ASE) noise generated by a
transmission system on the power consumption is investigated. As
a matter of example for 32×32 switches supporting 64 wavelengths
and offered traffic equal to 0,8, the average energy consumption per
bit is 5, 07 · 10-2 nJ/bit and increases if ASE noise introduced by
the transmission systems is increased.
Abstract: In this paper, we proposed an efficient data
compression strategy exploiting the multi-resolution characteristic of
the wavelet transform. We have developed a sensor node called
“Smart Sensor Node; SSN". The main goals of the SSN design are
lightweight, minimal power consumption, modular design and robust
circuitry. The SSN is made up of four basic components which are a
sensing unit, a processing unit, a transceiver unit and a power unit.
FiOStd evaluation board is chosen as the main controller of the SSN
for its low costs and high performance. The software coding of the
implementation was done using Simulink model and MATLAB
programming language. The experimental results show that the
proposed data compression technique yields recover signal with good
quality. This technique can be applied to compress the collected data
to reduce the data communication as well as the energy consumption
of the sensor and so the lifetime of sensor node can be extended.
Abstract: The CMLP building was developed to be a model for
sustainability with strategies to reduce water, energy and pollution,
and to provide a healthy environment for the building occupants. The
aim of this paper is to investigate the environmental effects of energy
used by this building. A LCA (life cycle analysis) was led to measure
the real environmental effects produced by the use of energy. The
impact categories most affected by the energy use were found to be
the human health effects, as well as ecotoxicity. Natural gas
extraction, uranium milling for nuclear energy production, and the
blasting for mining and infrastructure construction are the processes
contributing the most to emissions in the human health effect. Data
comparing LCA results of CMLP building with a conventional
building results showed that energy used by the CMLP building has
less damage for the environment and human health than a
conventional building.
Abstract: Environmental performance of the U.S. States is investigated for the period of 1990 – 2007 using Stochastic Frontier Analysis (SFA). The SFA accounts for both efficiency measure and stochastic noise affecting a frontier. The frontier is formed using indicators of GDP, energy consumption, population, and CO2 emissions. For comparability, all indicators are expressed as ratios to total. Statistical information of the Energy Information Agency of the United States is used. Obtained results reveal the bell - shaped dynamics of environmental efficiency scores. The average efficiency scores rise from 97.6% in 1990 to 99.6% in 1999, and then fall to 98.4% in 2007. The main factor is insufficient decrease in the rate of growth of CO2 emissions with regards to the growth of GDP, population and energy consumption. Data for 2008 following the research period allow for an assumption that the environmental performance of the U.S. States has improved in the last years.
Abstract: Energy intensity(energy consumption intensity) is a
global index which computes the required energy for producing a
specific value of goods and services in each country. It is computed
in terms of initial energy supply or final energy consumption. In this
study (research) Divisia method is used to decompose energy
consumption and energy intensity. This method decomposes
consumption and energy intensity to production effects, structural
and net intensity and could be done as time series or two-periodical.
This study analytically investigates consumption changes and energy
intensity on economical sectors of Iran and more specific on road
transportation(rail road and road).Our results show that the
contribution of structural effect (change in economical activities
combination) is very low and the effect of net energy consumption
has the higher contribution in consumption changes and energy
intensity. In other words, the high consumption of energy is due to
Intensity of energy consumption and is not to structural effect of
transportation sector.
Abstract: Modern applications realized onto FPGAs exhibit high connectivity demands. Throughout this paper we study the routing constraints of Virtex devices and we propose a systematic methodology for designing a novel general-purpose interconnection network targeting to reconfigurable architectures. This network consists of multiple segment wires and SB patterns, appropriately selected and assigned across the device. The goal of our proposed methodology is to maximize the hardware utilization of fabricated routing resources. The derived interconnection scheme is integrated on a Virtex style FPGA. This device is characterized both for its high-performance, as well as for its low-energy requirements. Due to this, the design criterion that guides our architecture selections was the minimal Energy×Delay Product (EDP). The methodology is fully-supported by three new software tools, which belong to MEANDER Design Framework. Using a typical set of MCNC benchmarks, extensive comparison study in terms of several critical parameters proves the effectiveness of the derived interconnection network. More specifically, we achieve average Energy×Delay Product reduction by 63%, performance increase by 26%, reduction in leakage power by 21%, reduction in total energy consumption by 11%, at the expense of increase of channel width by 20%.
Abstract: Thermal load calculations have been performed for
multi-layered walls that are composed of three different parts; a
common (sand and cement) plaster, and two types of locally
produced soft and hard bricks. The masonry construction of these
layered walls was based on concrete-backed stone masonry made of
limestone bricks joined by mortar. These multilayered walls are
forming the outer walls of the building envelope of a typical Libyan
house. Based on the periodic seasonal weather conditions, within the
Libyan cost region during summer and winter, measured thermal
conductivity values were used to implement such seasonal variation
of heat flow and the temperature variations through the walls. The
experimental measured thermal conductivity values were obtained
using the Hot Disk technique. The estimation of the thermal
resistance of the wall layers ( R-values) is based on measurements
and calculations. The numerical calculations were done using a
simplified analytical model that considers two different wall
constructions which are characteristics of such houses. According to
the obtained results, the R-values were quite low and therefore,
several suggestions have been proposed to improve the thermal
loading performance that will lead to a reasonable human comfort
and reduce energy consumption.
Abstract: In Iran, due to abundance of energy resources, energy consumption is extraordinarily higher than international standards and transportation sector is considered to be one of the major consumers of energy. Moreover, air pollution in urban areas as a result of high dependence on private vehicle and lower standards of vehicles, high subsidies spent on fuel and time waste due to traffic congestion in urban areas all have led to speculations on new strategies and policies in order to control energy consumption in transportation sector. These strategies and policies will be introduced in this paper and their consequences will be analyzed with consideration to socio-economic factors affecting the urban society of Iran. Besides, the intention is to suggest and analyze new approaches such as broader application of public transportation system, demand management in transport sector, replacement of deteriorated vehicles, quality improvement in car manufacture and introduction of substitute fuels.