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Thermal Energy Storage ( TES ) is an important technology to balance the hourly energy supply and demand in Building Cooling Heating and Power ( BCHP ) systems, aiming to lower primary energy consumption. The solid sensible TES and latent TES , which are relatively developed, have the potential to be generalized in BCHP systems. However, design problems such as what are the key parameters or how to get the optimal value for this specific application remain unclear. The objective of this paper is to give a theoretical method to solve those two problems. The fixed storage period constraint is taken into consideration, which was important but not considered in the published articles. Firstly, a new evaluation index called the non-dimensional cooling capacity is defined to evaluate the thermal performance of TES . Secondly, the key non-dimensional design parameters are found based on the mathematical model. Finally, the sensitivity analysis of those parameters is studied. The results can be applied to further understand TES in BCHP systems and are helpful to design BCHP systems. [ABSTRACT FROM AUTHOR]

Cities and Urban centers are hot beds for future innovation in the field of energy efficiency. At present, energy use in cities accounts for more than 60% of total world energy use and this trend is expected to increase with the growth in urbanization in various parts of the world. The role of Ecocities in this regard is of considerable importance. This paper discusses a model that was developed to assist the target setting in the planning process of an Ecocity in China. The Ecocity located in the Wuxi region in China, is currently in its planning stage. The model has been developed with a systems thinking approach, using STELLA. Different sectors comprising the Ecocity i.e. built environment, transport, water and waste management and energy generation have been considered. An effort has been made to take into account various possible synergies and feedbacks in the system that can be utilized to improve the performance of the overall system. An interactive interface has been provided to help different stakeholders in the decision making process. A participatory approach was adopted in the development of the model where different key parameters were identified as a result of a collaborative exercise with the various stakeholders. A framework for Participatory Modeling and Simulation has been developed. The model gives a possibility to visualize the energy saving potential for different technologies being proposed for implementation in the eco-city. Different scenarios have been created in conjunction with the identified sectors to reflect various levels of ambition towards energy saving in the eco-city. [ABSTRACT FROM AUTHOR]

In the last few decades, an increasing attention has been paid to the enhancement of energy performance and indoor comfort conditions of historical buildings, where the architectural heritage and artistic value do not allow typical retrofit intervention. The need to enhance the energy efficiency and environmental sustainability of historic buildings is addressed in this paper, through energy modeling and dynamic simulation of a real building with the integration of renewable energy plants for building heating and cooling. The pilot case study is “Palazzo Gallenga Stuart”, a historical university building located in Perugia, Italy. The energy performance of the building has been evaluated in order to reduce the building energy demand through the implementation of high-efficiency technologies in historic buildings. The increase of the energy efficiency of the building has been pursued through the improvement of the actual energy plants’ technology by introducing a more effective heat pump plant, in order to prevent the use of visually impacting external units on building historic façade. [ABSTRACT FROM AUTHOR]

This paper proposes a two stage Range-Adjusted model to assess the inefficiency and congestion of mix energy consumption. In order to investigate the case over time, DEA window analysis is combined with our model. The proposed two-stage DEA approach has been applied to examine the inefficiency and congestion in 16 APEC countries considering the energy mix effects from 1996 to 2011. Our results of empirical study show that the energy congestion in 16 APEC countries is still mainly due to the fossil energy, however, we also should take some useful measures to control the congestion comes from non fossil energy according to its rising trend in recent years. [ABSTRACT FROM AUTHOR]

Energy efficiency of water supply systems in high-rise residential buildings becomes a concern for sustainable development nowadays. It has been reported the energy efficiency for high-rise water supply systems is below 25% and more than 75% input energy is ‘lost’, about half of the energy loss attributes to water pumps. Water pump operating at low efficiency is highly undesired. This paper investigates the in-use water pump efficiency for water supply systems in high-rise buildings of Hong Kong. The pumping efficiencies evaluated from a survey of 20 high-rise water supply systems were presented as a function of installation time. Expressions of in-use pump efficiency were proposed and pump replacement time was suggested. Better performed pumps got longer suggested service period and poorer performed ones got shorter payback periods. More frequent replacement was suggested for larger pumps and the payback period was generally shorter. [ABSTRACT FROM AUTHOR]

Energy consumption by industrial sectors has possessed a large proportion of total energy use in many countries especially China. For the purposes of energy conservation, the government of China has implemented long-term policies to continuously assist thermal power industries in improving the energy efficiency. This paper investigates the short- and long-term causal relationship implied by the standard coal consumption per unit product of power (SCC), the rate of electricity consumption of power plant (EC), the total water consumption per unit product of power generation (WC) and the total oil consumption per year (OC). The result indicates that there is mutual influence among variables. The SCC is significantly correlated with the EC, a large amount of EC may impact SCC heavily. The OC is proved to be a new driving factor, and it has long-run equilibrium relationship with other three variables. [ABSTRACT FROM AUTHOR]

Improved understanding of ship energy use can be a crucial part of the process of increasing ship energy efficiency. In this paper, the methodology of energy analysis is applied to ship energy systems in order to showcase the benefits of such methodology. Data from one year of operations of a case study ship were used, together with mechanistic knowledge of ship systems, in order to evaluate the different energy flows. The identification of main producers, consumers and waste flows, allowed by the application of the method, leads to the suggestion of a number of possible improvements guided by the improved knowledge of the ship's energy system. [ABSTRACT FROM AUTHOR]

The energy efficiency of district heating (DH) systems can be increased by not only optimising the operational parameters of existing systems but also by integrating new elements into such systems. The paper recommends the installation of a high-temperature heat pump in the return water pipe system of a heating network in order to cover a part of the consumer's heat load. The authors provide a diagram for calculating the integration of a heat pump into the DH system and have also performed modelling in order to determine the changes in the network parameters over the course of a heating season if the heat pump has been working at a nominal capacity. The calculation model contains a system of equations that describes the mass and energy balances of the elements as well as changes within them over the course of a heating season. [ABSTRACT FROM AUTHOR]

China is the world's largest producer and consumer of household appliances, lighting and other residential and commercial equipment. Since 1989, China has developed and implemented over 40 energy efficiency (EE) standards and over 20 mandatory energy labels for a wide range of domestic, commercial and selected industrial equipment. However, there are tremendous opportunities to capture additional savings through more stringent energy efficiency policies for major energy-consuming appliances. To assess the stringency of EE standards, this paper developed an integrated products prioritization tool for energy efficiency standards improvements that comprises three component analyses: (1) analysis of market data, (2) quantification of energy savings potential, and (3) benchmarking China's EE standards to those of peer economies around the world. This integrated approach led to three independent but complementary studies, and an comprehensive analysis that resulted in a coherent set of policy recommendations on what products to prioritize for China's energy efficiency standards revisions, in order to maximize their energy savings. [ABSTRACT FROM AUTHOR]

Although it has been proven that systems for integrating energy flows of different businesses are technically possible, economically profitable and environmentally sound, few such systems have been realized in Norway. This paper shows that other aspects must be considered, and argues that such infrastructures should be understood as sociotechnical. We studied a regional cluster in Norway, Kviamarka, and how the businesses successfully integrated energy flows by integrating production processes in the energy system. The surplus heat, cooling water and CO 2 output that are byproducts of several companies in the cluster are used by other companies in the cluster, which makes it more energy-efficient. This case showed how integrating companies’ energy flows involve a material and structural bridging of the companies and a focus on the mutual trust and interdependence of the actors in order to establish and maintain a collective energy system. Establishing a system for synergizing energy flows involved solving issues regarding negotiation of roles and responsibilities as well as context-specific issues. We also report on findings from the project INTERACT, in which we studied sociotechnical issues in synergizing energy flows through different situations and scenarios. To study context-specific issues in other initiatives for creating energy-efficient systems, we developed a scenario typology. The scenarios are defined not by the technical properties of the system but by how the actors are bound together by the energy infrastructure and how that affects their respective roles and responsibilities. The typology highlights different core challenges and possibilities related to different socio-technical systems. The rationale behind energy efficiency is based on the idea that different flows of energy (surplus heat, cold etc.) can be synergized by connecting different actors. Thus, the potential for innovation lies in how actors are organized and use their complementary energy resources. [ABSTRACT FROM AUTHOR]

Residential, commercial and industrial buildings share nearly one-fourth of the total electrical energy consumption in Thailand. The design of energy efficient buildings relies on a selection of appropriate techniques that complement the local climate. The two important elements to be considered carefully in tropical climate are the cooling technology and the electrical appliances (including the lighting system). In this paper, the focus is on the design of residential and commercial buildings in a tropical climate. The literature data and the results from a case study in Thailand are gathered and a strategy for energy efficient buildings is proposed. In short, the design of the building envelope, the cooling technology and the efficiency of the appliances are the crucial factors in reducing energy consumption. This investigation shows that building energy demand could be reduced by as much as 28% through the use of low thermal conductance material alone for a building wall. [ABSTRACT FROM AUTHOR]

Abstract: In order to reduce energy consumptions for sustainable and energy-efficient manufacturing, continuous energy audit and process tracking of industrial machines are essential. Compared to other non-residential buildings that have been widely researched, industrial buildings are generally characterized by larger thermal loads, ventilation losses and pollution control requirements. This paper presents the results of a preliminary energy audit carried out on 8 large industrial buildings of a famous car manufacturing holding in Italy. Energy demand for heating varied from 6 to just over 74 kWh/m3year among the buildings of the site. The energy audit enabled to build a specific factory energy model which has been used in order to analyze the impact of various energy saving actions on the primary energy consumptions of the site. It has been demonstrated that in this specific case the improvement of the building envelopes and the optimization of the performances of the existing HVAC systems can determine a reduction of gas consumption up to 15% per year with a predicted annual economic saving of the order of 100000 €; the total simple pay-back time of the proposed thermal retrofitting is evaluated to be less than 6 years [Copyright &y& Elsevier]

Abstract: The full exploitation of locally available renewable resources together with the reduction of system installation and management costs are key issues of diffused Distributed Generation (DG). In the given context, hybrid systems are already at an advanced stage of development which typically integrate several sub-systems. In such hybrid systems, Renewable Energy Sources generation systems (e.g. photovoltaic panels) are coupled to energy storage devices (electric batteries) and with programmable generators (a diesel generator or, more recently, with a sub-system based on fuel cells) allowing stable operations under a wide range of conditions. In this paper a solution which uses hydrogen and fuel cells as a programmable source is presented and is studied by means of a mixed experimental and numerical: a Hardware-In-Loop test bench designed and realized at the Department lab, able to reproduce the behavior of a hybrid system for domestic applications. The system is controlled by means of a rule-based control strategy acting on the common DC-bus whose optimization has a significant influence both on system design and on its overall system energy performances. Results show that Rule-Based strategy have a great potential towards cost reduction and components lifetime increase, while energy efficiency mainly depends on correct system sizing. [Copyright &y& Elsevier]

Abstract: The twenty-first century has been a scenario for explosive investment in renewables. This paper examines such investment as well as the policies that support it. China represents a unique case in this regard due to its fast development. Whereas the issue of securing energy supply is becoming increasingly important over time, the energy return ratios, such as EROI, are important to evaluate the efficiency of energy production. A novel methodology is presented to identify the most convenient location to increase efficiency and energy return for renewables. The methodology also assesses the effects of renewables policies at different scales. [Copyright &y& Elsevier]

Abstract: Impact of users on thermal behaviour of a building and a building''s impact on the use of different spaces are two aspects that are subject of post occupancy evaluation of the present paper. The building was designed according to passive concepts, including Insulated envelope and internal thermal mass; also computer simulations were used to optimize thermal performance of different components of the design. The evaluation was done by using quantitative method to document climate and interior lighting. A qualitative method was also used for analysis of building use and perception of indoor climate by users. High windows were placed in the hall and lobby for night flush to cool the building during summer. However, the difficulty of opening them had led that night ventilation was never practiced. In winter, less window''s areas would be sufficient to satisfy the thermal comfort during the day while ensuring a sufficient level of natural lighting. Daylight level measured in the morning shows that the level of illumination is acceptable; however it remains below the required minimum during the afternoon during fall, winter and spring. Small to medium windows, (4-10% of floor area) on west orientation could improve the daylight during the afternoon. Also, a late closing of the youth club would be desirable for the spring, summer and fall when days are long. The results of the interviews describe a high level of satisfaction from users with regard to indoor climate. Bioclimatic design has a positive impact on the use of the youth. [Copyright &y& Elsevier]

Abstract: Under the frame of Total-Factor Energy Efficiency, considering desirable outputs and undesirable outputs taking by energy and related factors, this paper uses super efficiency DEA method to measure energy efficiency of 11 provinces (autonomous regions, municipalities) in western China from 1989 to 2009, and utilizes fixed effect model of variable intercept to analysis factors of influencing energy efficiency of provinces (autonomous regions, municipalities) in western China. The analysis shows that: (1) Under the situation of overall low energy efficiency in western China, in region, energy efficiency level presents the slow rise tendency from the year of 2005 after maintaining certain time interval slow drop. In the region the difference is small. (2) Factors of technical progress, industrial structure, government influence, opening degree, system variable as well as structure of energy consumption have different effects on energy efficiency, and these factors to action mechanism of energy efficiency exist difference. [Copyright &y& Elsevier]

Abstract: This article evaluated the energy effeciency in Hebei Province using some indicators such as comprehensive energy consumption, efficiency of energy transformation. Then it makes a comparative analysis about the HeBei Province''s status in the country''s energy conservation. The final part of the paper predicts energy consumption indicators in HeBei province from 2009 to 2013. [Copyright &y& Elsevier]

Abstract: TOTAL Exploration and Production is involved in a number of production and/or processing projects such as Heavy oil, Oil sands and LNG which require substantial amounts of energy (heat and power). Alongside this, sustainable development of energy resources is a prime target for the Total group, which strives constantly to reduce the GHG intensity of its production activities. On new projects and for major plant modifications, this is achieved by optimizing energy efficiency and preventing continuous flaring of produced gas, which is marketed or re-injected instead. On current producing installations, a continuous improvement process to address flaring reduction and energy efficiency is on-going. However in view of the coming development challenges, Total is further considering the development of facilities with a limited GHG footprint, by the means of emissions reduction through carbon capture and sequestration. Designing capture-ready installations is the first step on this path. It is a challenging task owing to the evolving nature of available technology, the high energy demand and correlative emissions of carbon and the unusual specific constraints in dedicated Oil and Gas energy plants. This paper presents our experience in this learning process applied to the oil & gas industrial environment. With the collaboration of Technip, Total initiated a study on the integration of carbon-capture solutions within cogeneration plants. On the strength of its in-house experience of oxy-combustion and acid gas removal, of transport and re-injection of acid gases, Total considered both oxy-combustion and post-combustion as promising technologies. The objective of the study was to assess the potential of each technology to tackle carbon capture on the two main types of thermo-mechanic converters present in a cogeneration plant: turbines and boilers, as well as evaluate the constraints. Alternative cogeneration plant concepts, with or without combined cycle were considered, to challenge further the impact of capture on cogeneration design. The actual operating conditions of a typical cogeneration plant burning clean natural gas, particularly its flue gas emissions, compatible with the target project’s constraints, were proposed as the design basis for capture systems of various scales. The requirement to keep to simple capture concepts was critical in view of the challenging economic environment of carbon capture, the evolving technology and the probable tightening of emission-reduction targets. Due to the uncertainties as to the final fate of the carbon dioxide, EOR or/and geo-storage, nearby or distant, in depleted fields or saline aquifers, being considered, several CO2 conditioning process options were defined. The integration of capture-ready building blocks within the plants was a significant step in the design process for alternative cogeneration plants, and enabled the synergies and constraints of operating the capture systems to be identified. The key risk items were highlighted, offering insight into the expected roadmap of the capture technology development. The results of this work compare the main features of the oxy-combustion and post-combustion CO2 capture technologies for steam-boiler and/or gas-turbine effluents and flag up some essential local constraints affecting the performance of the various capture-ready cogeneration schemes. [Copyright &y& Elsevier]

Abstract: The California Global Warming Solutions Act of 2006 sets a goal for the state to reduce its greenhouse gas emissions to 1990 levels by 2020. In preparation for implementation of a cap and trade program under this Act, Chevron has undertaken a detailed assessment of greenhouse gas mitigation options and costs. Such an assessment is key to making compliance decisions within the constraints of a given cap and trade regime. If the cap and trade market is minimally restricted (i.e., recognizes that climate change is a global issue and thus has no geographic restrictions and no set requirement for onsite emission reductions), facilities can make the best economic (and environmental) choices of where to ‘make’ emission reductions inside the facility fenceline and when to ‘buy’ the emission reduction allowances or credits on the market. The scope of the study included Chevron’s two refineries and a large heavy oil steamflood production operation in California. This paper will discuss how mitigation technologies are identified and assessed, describe some of the key greenhouse gas mitigation alternatives of interest to the Chevron California facilities and present a business-based approach to analyzing mitigation costs. Technologies studied included energy efficiency, advanced energy (solar, wind, geothermal, biomass, nuclear, low temperature heat recovery) and carbon dioxide capture and storage (CCS). For each mitigation option, a consistent methodology, based on the International Petroleum Industry Environmental Conservation Association/American Petroleum Institute (IPIECA/API) Guidelines for Evaluation of Greenhouse Gas Emission Reduction Projects was used to assess baseline or ‘business as usual’ emissions, net emission reductions due to the project, capital cost, operating cost and any project benefits (e.g., reduced fuel use for energy efficiency projects). These values were then entered into a business evaluation tool to calculate a Net Present Value for each option. Key conclusions: [•] Broad involvement of various disciplines is needed to identify new alternatives for greenhouse gas mitigation technologies. [•] Other than CCS, options for significant reductions of refinery and petroleum production emissions were extremely limited in the facilities studied. [•] Since cost-effective, feasible options are limited for refineries and petroleum production facilities, availability of sufficient allowances and offsets is an important element if state goals are to be achieved. [•] Although a number of energy efficiency projects were identified, the cumulative total emissions reductions available through energy efficiency projects is minimal. [•] Renewable and advanced energy projects that generate electricity generally have very high mitigation costs, and may not greatly benefit facilities if emission caps apply only to direct emissions, since these projects reduce the quantity of purchased electricity rather than emissions from the facility itself (and are therefore not eligible for credit under most regulatory design schemes). [•] Renewable and advanced energy technologies for steam generation may have significant mitigation potential for heavy oil steamflood production. Further development and demonstration is needed to determine whether these technologies will be viable. [•] In order to support good business decisions, it is important that greenhouse gas mitigation technology evaluation be done in a manner consistent with other business evaluation processes. [Copyright &y& Elsevier]