Search results for "consumption"
showing 10 items of 1796 documents
Cost and safety issues of emerging technologies against conventional techniques
2015
Abstract The industrialization of recovery processes is governed by several factors such as scale-up boundaries, product safety, and overall cost. Thereby, improved process efficiency is considered in terms of cost minimization via reducing processing steps and restricting overall energy consumption. The emerging nonthermal technologies promise to overcome the obstacles of conventional techniques with regard to energy requirements, but in some cases this has not yet been achievable. In this chapter, an attempt to clarify cost issues of conventional and emerging technologies is conducted. Moreover, other aspects such as safety issues are discussed, as the facilitation of healthy food additiv…
Multicriteria evaluation of carbon-neutral heat-only production technologies for district heating
2018
Climate change mitigation requires reducing dependence on fossil fuels and transition to low carbon energy production technologies. Nearly half of the global final energy consumption is thermal energy produced from technologies with high carbon dioxide emission. As such, it is imperative to employ carbon-neutral heat production to achieve a sustainable energy system. This paper presents a real-life case of applying multicriteria decision analysis for evaluating carbon-neutral heat-only production technologies in a major district heating system in Finland. A group of 10 experts from the energy company contributed in defining the alternative technologies and multiple economic, technological, …
Short-term prediction of household electricity consumption: assessing weather sensitivity in a Mediterranean area
2008
Abstract Urban microclimatic variations, along with a rapid reduction of unit cost of air-conditioning (AC) equipments, can be addressed as some of the main causes of the raising residential energy demand in the more developed countries. This paper presents a forecasting model based on an Elman artificial neural network (ANN) for the short-time prediction of the household electricity consumption related to a suburban area. Due to the lack of information about the real penetration of electric appliances in the investigated area and their utilization profiles it was not possible to implement a statistical model to define the weather and climate sensitivities of appliance energy consumption. F…
APPLICATION OF MATHEMATICAL MODELS FOR THE SIMULATION OF THERMAL COMFORT CONDITIONS IN A LIVING ROOM
2005
The paper deals with the distributions of temperature and averaged turbulent airflows in living rooms in 2D and 3D approximations using Ansys/Flotran and Ansys/CFX software respectively. The distributions are calculated depending on the placement and temperature of heaters, heat transfer coefficients of the building structures and ventilation conditions. The authors analyse the influence of these factors on the air circulation and the related heat flows through building structures. The thermal balance of a room and its dependence on various external factors is also considered. As thermal comfort conditions’ parameters are analysed, the airflow velocities and indoor temperatures with its gra…
Robust Multi-Objective Optimal dispatch of Distributed Energy Resources in Micro-Grids
2011
Modern distribution systems are implemented through micro grids: small power networks where generation is close to consumption and ICT supports the coordinated management of the different energy resources. In such systems, the central control unit manages energy dispatch from the different sources according to different criteria (technical, economical and environmental) and takes care of tertiary regulation. Such optimization for the tertiary regulation is performed with a time interval that typically is of 24 hours. This is due to the fact that it is necessary to take into account the charge and discharge cycles of storage systems. On the other hand, such long time leads to large errors in…
Long term energy efficiency study on different wall envelopes in Latvian climate conditions
2017
Abstract Five test stands have been built in Riga, Latvia equipped with sensors (temperature, solar radiation, humidity, etc.) to measure energy efficiency and thermal comfort conditions. Roof and floor constructions are made the same. For the walls building envelopes differ and typical materials used in Latvia (aerated concrete, ceramic building blocks, wooden log and plywood frame with rock wool insulation) are compared. Only rock wool is used for insulation to provide moisture transport through the construction. For study to be comparative thermal transmittance of all five test stands have been calculated equal (U=0.15…0.16 W/(m 2 ∙K)). The aim of research is to compare the integral calc…
UAQ4 Levitating Train: Italian Maglev Transportation System
2014
This article illustrates the University of L'Aquila model 4 (UAQ4) Italian maglev train, a transportation system with zero motion resistance (except aerodynamic drag) and greatly reduced energy consumption, approaching zero at a low constant speed. The project is the result of more than 40 years of research in the field of nonconventional highspeed transportation systems. Its technological feasibility has been tested in the laboratory at the University of L'Aquila, Italy.
A cooperative lifetime extension MAC protocol in duty cycle enabled wireless sensor networks
2011
To reduce energy consumption in wireless sensor networks, the concept of duty cycle is used in many MAC protocols. Although these protocols provide efficient energy-conservation solutions, they cannot resolve the energy hole problem in a multi-hop network, where a few nodes near the sink must relay the packets from the rest of the network, and consequently exhaust their batteries earlier. The previously proposed REACT forwarding protocol triggers the cooperation of several nodes to extend transmission range and hop over the highly burdened node, thereby allowing it to save its energy and extend the lifetime of the network. However, the previous work lacked a MAC protocol with a duty cycle. …
Improving the sustainability of transportation: environmental and functional benefits of right-turn by pass lanes at roundabouts
2015
The functional performances of conventional roundabouts (single-lane and multi-lane) and innovative roundabouts (spiral, flower, C and turbo) can be improved through right-turn bypass lanes controlled by stop, yield or free-flow signs. The article presents evaluations of the emissions of air pollutants (carbon dioxide, nitrogen oxides, particle pollution (PM10 and PM2.5)), fuel consumption and construction, management, energetic and environmental costs in roundabouts without or with bypass lanes (controlled by stop, yield or free-flow). The suggested methodology has a general character and can be applied as a multi-parametric criterion for choosing road intersections, although, in the prese…
On the Sustainability Evaluation in Sheet Metal Forming Processes
2011
In sheet metal forming processes there is still a lack of knowledge in the field of environmental sustainability mainly due to the need of a proper modeling of issues and factors to be taken into account. Such topic is, nowadays, a urgent and remarkable issue in manufacturing and the main concerns are related to more efficient use of materials and energy. What is more, the estimation of environmental burdens of forming technologies is very complex to be accomplished since it is essentially process-dependent. This means that when comparing, for instance, a traditional forming process with an innovative one, there are some peculiar aspects to be considered; actually, processes can be rather d…