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The present paper describes an energy efficiency project (and relevant authorities proceedings) related to a 100 MWe CHP located within an industrial facility in Italy (COD 1996). The CHP plant supplies steam and electricity to the industrial process, whilst the extra electric-energy generation is sold to the grid. Main project target was to increase the global operating and economic indicators by: • Modifying the plant in order to cope with different thermal needs from the industrial process; Obtaining the incentives named TEE – Titoli di Efficienza Energetica , related to the CAR scheme; • Reducing CO 2 emissions (“Quote CO 2” ). • Increasing the CHP global efficiency; As several European CHP plants are nowadays facing operation/performance limitations due to different actual thermal loads (typically lower) compared to the design ones; the project has hence the aim to combine the need of a plant retrofit and the eligibility for the CAR incentives, providing a financial support to the retrofit, which corresponds, in project case, to a PBT of less than 2 years. The project and iterations with GSE are still ongoing. [ABSTRACT FROM AUTHOR]

Photovoltaic technology is a consolidated solution for electricity production in residential, commercial and industrial facilities. Despite that, the solar-to-electrical energy conversion is still low and many efforts are still needed in order to increase the panel efficiency. Since the photovoltaic modules performance decreases when the cell temperature increases, solutions have been investigated to cool down the panel with a refrigerated thermal plate installed on the PV rear surface. In standard applications, the photovoltaic thermal panel (PV/T) systems can produce both thermal and electrical energy and they are typically used for domestic hot water (DHW) production. Moreover, hybrid solar panels must be coupled with a heat pump system at the evaporator side, realizing a photovoltaic solar assisted heat pump (PV-SAHP) plant. Generally, a careful design of these integrated systems must involve accurate control strategy to optimize energy savings during operation. In fact, the behavior of the PV/T panels is heavily influenced by the very quick variation of the external conditions during daytime (mainly due to solar irradiation), affecting the working conditions of the other equipment. Therefore, models able to reproduce the dynamic behavior of the PV/T panels represent a flexible tool for developing innovative and user-adapted system control criteria, in a global system optimization perspective. In this context, the aim of the present paper is to describe a simplified numerical model able to reproduce the short time dynamic behavior of the PV/T panel. The model has been validated using experimental data which have been collected during outdoor tests conducted at the University of Genoa using a prototype realized by retrofitting a commercial PV collector. Several simulations have been performed by comparing the PV/T outlet temperature provided by the numerical model against experimental data. [ABSTRACT FROM AUTHOR]

Energy efficiency is nowadays a subject deeply discussed in several fields, with a large potential in industry. Here proper process and energy management routines turns out to be essential to reduce the energy demand while keeping the control of the product quality. In this respect the bread baking, one of the pillar of food related industry, is an energy intensive process irrespective to the adopted oven technology or to the primary energy nature. Baking is the fundamental step of the bread production process and it entails a number of complex chemical and physical phenomena, critical to the final physical properties of bread, i.e. crust colour, crumb texture and taste. A careful balance throughout all the steps of the “manufacturing” cycle is vital to ensure the processes synchronization, in order to produce a consistent and satisfactory loaf of bread. A proper energy management of this process needs to consider such features to ensure a high quality product. As such process monitoring can not be conveniently described using customary specific energy metric (correlating the energy demand to the amount of processed material) or full three-dimensional (3D) physic-based modeling as in computational fluid dynamics (CFD). In this paper, the energy analysis of the system is carried out with a methodology rooted in the family of non parametric approaches. The aim of the study is to identify key performance indicators (KPIs) able to assess the effectiveness of the energy “use” along the baking process. Specifically, the identification of KPIs is carried out using Principal Component Analysis (PCA) of the available datasets. [ABSTRACT FROM AUTHOR]

In this paper the energy design and the optimization of a non-residential NZEB conceived for Mediterranean climates are discussed. The presented NZEB will be built up in Naples (South-Italy). The building will include offices, expo spaces and a conference room. Different innovative energy efficiency strategies, regarding the building envelope and plants are taken into account. Their benefit in terms of energy performance is assessed by a novel in-house developed building energy performance simulationcode (DETECt 2.2) written in MatLab. An optimization procedure and a sensitivity analysis of the pivotal design and operating parameters are carried out from both the energy and economic points of view. The obtained numerical results show that interesting energy and economic savings can be achieved. Results can be useful for stakeholders working on non-residential NZEBs in temperate climates. [ABSTRACT FROM AUTHOR]

Land transport is the major mode of transportation in Laos where it has consumed about 96% of total energy consumed in the transport sector. This paper investigates the effectiveness of the policy packages, which includes counter measures (CM) relevant to the transport sector, namely 1) fuel switching, 2) advanced technology and 3) modal shift to reduce energy consumption and CO 2 emission during 2010-2050. In this study, the Long-rang Energy Alternative Planning (LEAP) model was applied to forecast sector-wise transport demand. Results show that the energy consumption in the transport sector will be increased from 548 ktoe in 2010 to 2,823 ktoe in 2050 while CO 2 emission will be increased from 1,656 kt-CO 2 in 2010 to 8,511 kt-CO 2 in 2050. However, implementation of four mitigation actions will reduce energy consumption by 9.3% and CO 2 emission by 20% when compared with the BAU scenario. [ABSTRACT FROM AUTHOR]

One of most important concerns in electrical power markets and distribution network is supplying the customer demands. It is necessary to forecast the usage of electrical power in distribution network. The pattern of electrical power usage depends on many different parameters such as the density of population in those areas, the week days, weather condition and etc. However, the electric utilities and regulators face difficult challenges evaluating new energy efficiency and smart grid programs prompted by recent state. In this paper, it is tried to forecast the electrical power usage according to above parameters by using artificial neural network base on service sharing strategies regarding that can help meet their energy efficiency policy goals. It is tried to find out the pattern of electrical power usage with the dataset which is prepared by real data. Therefore, it has been used here is useful in all kind of power forecasting such as short term, middle term, and long term. It can be helpful to manage the distributed generators production schedule and also correction of electrical power usage. [ABSTRACT FROM AUTHOR]

The goal of energy efficiency in buildings is a driving force for constant innovation in the construction industry. The opportunities are searched either in cutting edge solutions but also in basic components. The development of thermal renderings and thermal plasters is a recent trend in the market, which aims at lowering the envelope's U-Value with upgraded thermal resistance of its components. The paper has the objective of presenting evaluation schemes that demonstrate the potential and allow for durability assessment of a gypsum based thermal plaster to be applied as interior rendering on walls and ceilings. The first part of the work focus the laboratory characterization of the product. It relies on the addition of low weight aggregates to reduce density and hence heat conductivity. In addition to a lower conductivity, these materials demonstrate a higher moisture capacity, resulting in a solution that can present benefits not only for energy efficiency but also for the passive control of relative humidity. Accelerated ageing tests were also performed, to assess the durability of the product. In a second part, hygrothermal simulations were performed to evaluate the potential benefits of the product and to detect hygrothermal risks that can result from its application in specific environmental conditions. [ABSTRACT FROM AUTHOR]

Due to the fact that efficiency of PV panels decreases by approximately 0.5%/K, possibilities to stabilize the temperature on the panel's surface are considered in this paper. The aim of this investigation is to determine the transition temperature of PCM layer that allows avoiding rapid temperature fluctuations on the PV back surface. To meet the stated goal, dynamic simulations of thermal and electrical performance of PV/PCM panels were carried out using ESP-r software. Based on the obtained results, it can be concluded that additional PCM layer on the back side of PV panel can effectively increase the efficiency of electricity production with PCM transition temperature about 20 °C. [ABSTRACT FROM AUTHOR]

This paper presents energy efficiency improvement and CO 2 mitigation in the residential sector between Indonesia and Thailand. The Long-range Energy Alternative Planning (LEAP) model was used to analyze future energy demand and CO 2 emissions during 2010-2050. This study applied the Demand Side Management (DSM) options to reduce CO 2 emissions in the residential sector by implementing energy efficiency improvements such as efficient lighting, cooking, cooling and entertainment devices. The results indicate that in the business as usual (BAU) scenarios between 2010 and 2050, for Indonesia the energy demand will increase from 18147 ktoe in 2010 to 36044 ktoe in 2050. By adopting these scenarios, energy will be saved by 27.6% of total energy demand in 2050 while cumulative CO 2 emission can be reduced by 16% of overall CO 2 emissions in 2050. For Thailand, the energy demand will increase from 1879.1 ktoe in 2010 to 3167.8 ktoe in 2050. The energy will be save by 15.5% of total energy demand in 2050 and cumulative CO 2 emission can be reduced by 13.36% of overall CO 2 emission in 2050. [ABSTRACT FROM AUTHOR]

The main goal of this paper is to evaluate the influence of a heating system control program and thermal mass of the external envelope on the internal thermal comfort. The analogous influence was considered based on the final energy consumption for heating purposes. A building that was chosen for the purpose of the analysis is located in Warsaw. This building fulfils national requirements. To evaluate the problem, various programs for heating system control were applied: constant space temperature, and reduced space temperature. Besides that three kinds of external walls were chosen. To obtain the results the simulation program was applied. [ABSTRACT FROM AUTHOR]

In this paper the performance of the following retrofit actions on an existing historical public building were dynamically simulated by using the simulation software TRNSYS: a) utilization of thermostats for indoor air temperature control with 20 °C and 18 °C as target temperatures; b) increment of current thermal insulation of opaque walls and windows; c) replacement of the current diesel-fired boiler with a natural gas-fired condensing boiler. The simulation results were analyzed from both energy and economic point of views in order to assess their energy saving potential and economic suitability. [ABSTRACT FROM AUTHOR]

Energy requirements for space heating and domestic hot water supplies in the Swedish building sector are responsible for almost 60% of the total energy used. To decrease this enormous figure, energy saving measures are required, as well as opportunities to use low-temperature heating systems for increase sustainability. The present paper studies low-temperature heating systems, including heat production units (district heating or heat pumps) and heat emitting units in the room. The aim was to find an answer to the question of whether or not low-temperature heating systems are energy efficient and sustainable compared with conventional heating systems. To answer this question, we considered different efficiency aspects related to energy and exergy. The analysis showed that low-temperature heating systems are more energy efficient and environmentally friendly than conventional heating systems. This was attributed to heat pumps and district heating systems with lower temperature heat emitters using a greater share of renewable resources and less auxiliary fuels. This report discusses the pros and cons of different types of low-temperature heat emitters. [ABSTRACT FROM AUTHOR]

In 2008 the German Ministry of Economic Affairs and Energy launched an initiative for new or retrofitted energy-efficient school buildings as focus area within their research programme “EnOB” (Energy Optimised Buildings). The initiative ( www.eneff-schule.de ) comprises three different energy levels: • Best practice schools with energy-efficient renovations above the requirements in the energy-saving ordinance • Three-liter-house schools with energy needs for heating, hot water and auxiliary below 34 kWh/m 2 year • Plus energy schools that produce more energy than they use in the annual balance Currently three different plus energy school buildings have been planned, realized and monitored within the initiative, two of them being renovations (Stuttgart and Rostock), the last one being a new school building (Hohen Neuendorf). The three energy concepts include rather different technologies to generate heat and to reduce the energy consumption of ventilation and lighting systems. This is partly due to the research initiative approach of “EnEff:Schule” that asks for testing innovative technologies. There is however a general tendency to: • Low U-values of the building envelope with about 0.11–0.15 W/m 2 K at the walls and roof, 0.10 W/m 2 K for new base plates and 0.20–0.34 W/m 2 K for renovated ground slabs and basement ceilings and 0.80 W/m 2 K for windows • Large PV areas to compensate for the remaining energy use, sometimes in combination with other technologies or systems that generate electricity • Mechanical ventilation systems with high heat recovery rates but in combination with natural ventilation • User-dependent control strategies for ventilation and heating • Use of daylight at both the window/solar shading side and the electrical lighting control The paper compares the different technologies used at the building envelope, the heating, ventilation and lighting systems, the calculated and measured energy consumptions and the building costs. [ABSTRACT FROM AUTHOR]

Residential and commercial buildings consume 66% of the electricity and 33% of all energy in the United States and are therefore considered as a key sector to review for energy savings. Early studies have reported a great potential for achieving cost-effective energy efficiency in buildings through influencing behavioral change. However, it still remains a serious challenge to avoid negative boomerang effects in consumer behavioral change. Likewise, it is unclear how the lacking factor of the personality trait, which is vital to the success of normative feedback approach, shapes energy-related behaviors. To address these challenges, this paper presents a model-based approach to simulate the process of energy behavior change. Based on a modified opinion dynamics model, this study 1) explains the personality-behavior relations and acquires the elementary rules of behavior change by testing different treatment strategies; and 2) develops a personality trait-based energy reporting mechanism to lead behaviors towards more a favorable and sustained energy conservation movement. [ABSTRACT FROM AUTHOR]

Museum storage buildings should be able to provide a considerable stable indoor environment in terms of temperature and relative humidity (RH). To obtain such stable conditions with the lowest possible energy consumption, passive air conditioning is one-way solution. In this paper, indoor environment facilities of a passive museum storage building in Vejle region in Denmark, are investigated. Results demonstrate that the weather conditions of the previous yearś considerably affect the indoor environment of the storage. What is more, concentrated dehumidification is a sufficient technique to maintain RH within acceptable levels. Therefore, renewable energy such us excess wind energy during the night can be utilized. [ABSTRACT FROM AUTHOR]

Pressure differences between outdoors and indoors influence indoor environmental quality (IEQ) and building physics of the building envelope. This paper focuses on measurements of pressure difference values of about 152 apartments from 26 multi- family buildings in Finland. Measured data include pressure differences between indoor spaces and both outdoors and staircases before and after renovation. In buildings equipped with mechanical exhaust, the pressure differences between indoors and outdoors before renovation varied from +10,1 to -95,0 Pa (average -7,8 Pa), and between indoors and staircases from -3,5 to -6,0 Pa (average -18,6 Pa), being lower than -5 Pa in 36% of the buildings. In naturally ventilated buildings, the pressure differences between indoors and outdoors were lower than -5 Pa in 44% of the buildings. The average pressure differences after renovation in nine buildings equipped with mechanical exhaust were slightly higher (-19,1 Pa against outdoor and -9,0 Pa against staircase). A possible reason for higher negative pressure could be that the airtightness of building was improved by renovation, but the ventilation system was not balanced accordingly. Improving energy efficiency (EE) could effect on pressure difference either positively or negatively. Measured pressure difference between indoors and outdoors or staircase before and after renovation could be a possible indicator when assessing the impacts of improving EE on IEQ and occupant satisfaction. [ABSTRACT FROM AUTHOR]

This paper has as its main focus to define the drivers of retrofitting shopping centres. The drivers will provide the basis for developing energy retrofitting concepts, offering amongst other things, constructive technology, an understanding of typical functional patterns and socio-cultural aspects and an understanding of potentials associated with interaction with local energy grids. The primary focus of the study is energy use, but the fields of facilities, functions, management, ergonomics, safety and logistics are also studied, because sustainable shopping centres in addition to being energy efficient are commercially viable, accessible social arenas for all sections of society. [ABSTRACT FROM AUTHOR]

The European construction sector (a fragmented SMEs dominated business with high economic and environmental impact and high technological inertia) faces a major challenge to reduce the emissions by almost 90% in 2050. This requires new innovative solutions and services to be rapidly implemented in the market. Research Infrastructures that give support for later-stage developments (high Technology Readiness Levels) can play a relevant role in both the technological development and market introduction of construction products for energy efficient buildings. The following paper describes such an infrastructure (KUBIK by Tecnalia ) located in Bilbao (Spain) and its major outcomes in the period 2011-2015. [ABSTRACT FROM AUTHOR]

Building energy monitoring and real time control strategies can decrease energy consumption on one hand, and improve comfort on the other hand, by increasing the understanding of the control system. A decision support system for building energy management can be a proper tool for supporting the measurement and management of energy usage and costs of public buildings. The aim of the paper is to describe the architecture of the Decision Support System (DSS), that is being developed within the FP7-Smartcities Project OPTIMUS (OPTimising the energy Use in cities with smart decision support system). The architecture of the system is described considering both the energy related and the information technology aspects. An example of action modeling is also presented and the first results are discussed. [ABSTRACT FROM AUTHOR]

In this paper we would like to show the readers two case studies of energy-, environmentally- and cost-efficient renovations of contemporary buildings in Czech Republic that were assessed according to the IEA ECBS Annex 56 methodology - elementary school Kamínky 5 (built 1987) and block-of-flats Koniklecová 4 (built 1983). Both buildings are located in Brno – Nový Lískovec. They were recently renovated into low-energy standard, with emphasis on low renovation costs and high operating cost savings. In both cases the renovation reduced energy consumption by approximately 60%. It also improved wellbeing of the users and visual perception of the buildings. [ABSTRACT FROM AUTHOR]

In this paper we present the results from field studies of two low-energy office buildings in California, both using radiant slab ceiling systems (thermally activated building systems, TABS) for primary cooling and heating in the buildings. Both buildings are certified LEED Platinum and incorporate a wide range of energy efficient technologies and design strategies, including TABS, advanced shading systems, underfloor air distribution, chilled beams, ceiling fans, natural ventilation, and photovoltaic panels. Findings and analysis from the following building performance assessment techniques will be discussed. • Occupant satisfaction survey. Occupant surveys are an invaluable source of information for describing how well the building is providing a high quality indoor environment for the occupants. In addition, the survey results are also compared against a large benchmark survey database of over 50,000 occupants. • Wireless measurement system. A network of wireless sensors was installed in selected zones of the buildings to provide additional more detailed information about the operation and control of the radiant slab system. This data was combined with trend data from the building management system (BMS) to examine the performance of the buildings during both winter and summer conditions. Some control issues were identified and corrected based on these measurements. • Energy performance analysis. We collected utility data for 2014 in one of the buildings and used this information to determine the building's Energy Star rating. [ABSTRACT FROM AUTHOR]

Airflow pattern in a data center impacts the cooling effectiveness of the air-conditioning systems significantly, and hence impacts the energy efficiency of the whole data center. This paper presented investigation of the airflow pattern for a typical data center by CFD simulation. An under-floor air supplying system was used in the targeted data center. Cooling performance of the original and three more modified airflow pattern was simulated by CFD software. In optimizing the cooling efficiency, the measurements including blanking of the unused rack space, adding vertical partitions, and partly enclosing cold aisles were adopted to modify the original airflow pattern. The cooling performance was compared by indices like Supply Heat Index (SHI), Return Heat Index (RHI), Rack Cooling Index (RCI) and Return Temperature Index (RTI). The results indicated that partly enclosing cold aisles got most significant improvement in cooling performance. The supply air temperature could be increased by 3 °C. While for the index itself, RTI was found not appropriate in evaluating of cold air by-pass or hot air re-circulation in some cases. [ABSTRACT FROM AUTHOR]

In this paper we present the most innovative aspects of the EC-FP7 EcoThermo project. The main aim of the project consists on innovating the technique of heat cost allocation in buildings with a centralized heating system, overcoming the heat cost allocator drawbacks for reliability, measurement reproducibility and traceability and contexts of applications. Given the complexity of the project, we will focus on its main aspects, such as the use of a virtual sensor to estimate the radiators heating power, the design of electronic valves fitted out with an energy harvesting system and the original wireless communication protocol. [ABSTRACT FROM AUTHOR]

Energy demand imputable to buildings corresponds to around 40% of the total in most of the developed countries, showing the great potential in this field to propose and implement effective strategies for energy saving and environmental sustainability. Additionally, urban areas are the most impacted zones by anthropogenic sources and they are often affected by local climate phenomena such as urban heat islands. In this view, several measures to mitigate this effects and to save energy in constructions are dealt with the implementation of cool materials for roofs and urban paving. Since the majority of cities in Europe is characterized by traditional architectures in residential buildings, the implementation of white cool coatings is not feasible and new solutions are being proposed. In particular, starting from previous works of the authors about the development and continuous monitoring of cool clay tiles, this paper deals with the thermal analysis of low-visual-impact cool tiles in single family residential buildings with varying climate conditions (i.e. latitude) in Europe, from hot subtropical semi-arid climate (Tripoli) to oceanic climate (Munich). A calibrated and validated simulation model by mean of experimental in-lab and in-field measurements, has been used for studying the thermal effect of the proposed clay tiles. The analysis shows how the clay tile has a promising potential to decrease the indoor overheating in all the climate conditions, with relatively low penalties in winter even in the coldest areas. [ABSTRACT FROM AUTHOR]

Deep underground mining is highly energy intensive due to the need to overcome high pressure rise required by ventilation fans, high cooling load in summer due to rise in rock temperature and the auto-compression effect, and heating requirement in winter. Rising energy costs have led the mining industry to look for alternatives in energy-efficient systems to reduce the operating costs as well as to reduce the carbon footprint. This paper addresses the challenge by utilizing naturally available renewable energy source from seasonal cycle for heating and cooling of underground mines: heat in the summer is stored in the rock-pit to be used for heating in winter, and the “cold” energy in winter is captured and is stored in the rock-pit for cooling during summer. A three-dimensional unsteady local thermal non-equilibrium (LTNE) model is developed to evaluate thermal storage and heat transfer between ventilation air and rock-pit (large broken rock mass). The results suggest that the seasonal thermal energy storage (Se-TES) of rock-pit is able to assist thermal management in underground mine and to reduce energy consumption for winter heating and summer cooling. The ventilation air temperature is about 15 to 20 ˚C higher/lower as compared to ambient temperature in winter/summer, respectively. Clearly, this shows potential application of large scale Se-TES in mining industry. [ABSTRACT FROM AUTHOR]

The building sector is a large consumer of the world's energy and is responsible for 40% of the European Union's (EU) total final energy consumption. The most effective and efficient method to reduce energy consumption of buildings is to retrofit existing buildings with more energy efficient facilities. This paper presents a multi-objective optimization model for building envelope retrofit planning which aims at maximizing energy savings and economic benefits with given investment budget. It also takes thermal comfort and life-cycle impact into consideration. Results from application to the retrofit planning of a 70 years old family house show that energy consumption can be reduced effectively by the presented model. [ABSTRACT FROM AUTHOR]

Energy efficiency in the demand side is considered one of the cheapest ways to achieve reductions in Green House Gases emission, as well as to avoid heavy investments in production, transmission and distribution of electricity. In the context of the Emirate of Abu Dhabi, UAE, where buildings (residential, office, retail and villas) consume about 87% of the electricity, most of which is devoted to indoor air-conditioning, energy efficiency has a huge potential for development. Under the current political/economical scenario, a series of measures to diversify the economy and attract expatriates are in place. These include heavy subsidies on retail electricity prices—which has the side-effect of limiting the economic feasibility of investments in energy efficiency. In this study, a series of building retrofits were tested on a model of the average office building in the Emirate. The best performing retrofit was identified to be the chiller's Coefficient of Performance (COP) improvements, having the lowest cost/benefit ratio and resulting in an overall annual electricity savings of around 12%. Under the current subsidized electricity price, investments in energy efficiency of existing buildings are not attractive for the owner-consumer, as over the lifecycle of the measure, the return on investment is low or negative. In this paper we attempt to assess the applicability, in the Emirate of Abu Dhabi, of energy saving obligations and tradable white certificates as a mechanism to enable investment in demand-side energy efficiency and achieving average investment returns of 7% over a 25 years horizon. The application of white certificates can enable the market of energy efficiency to develop in the Emirate. The economic return of applying a chiller retrofit under the studied white certificate scenario avoids the increase of 17% of current electricity prices. [ABSTRACT FROM AUTHOR]

In this paper, both energy efficiency and environmental efficiency of coal-fired power units are studied based on the non-parametric data envelopment analysis method (DEA). Compared with energy efficiency, the emission of SO 2 and NO x are taken into consideration for the environmental efficiency. The ST model is employed to calculate pure technical efficiency. And the strong disposability model is used to calculate the environmental efficiency. Analysis and comparison for energy and environmental efficiency are conducted. By comparing the influence of ownership factor on these two kinds of efficiency, it can be found that the China Guodian Corporation ranks the first in both the energy and environmental efficiency. China Datang Corporation ranks the third in energy efficiency while ranks the last one in environmental efficiency. [ABSTRACT FROM AUTHOR]

The shipping industry is focusing more and more on reducing fuel consumption and greenhouse gas emissions. A non-negligible amount of fuel is consumed while ships are in port, waiting for loading or unloading, for heating up accommodation spaces and fuel tanks, while when at sea waste heat from engines exhaust is under-used because of low demand. In this paper we propose the use of thermal energy storage as a solution for the mismatch between heat availability and demand. A simplified system is proposed and the influence of design parameters (storage size, heat exchangers surface, secondary fluid mass flow rate, storage temperature) on the performance of the system is analyzed. The results of the application of a thermal energy storage system to a case study ship show that the installation of a storage tank of 1000 m 3 could reduce the fuel consumption from the boilers by 80%, which would lead to yearly savings of 268,000 USD. This preliminary analysis shows that there is potential of both economic and environmental benefits from the application of thermal energy storage to merchant vessels. [ABSTRACT FROM AUTHOR]

Increasing the building sector's energy efficiency while reducing CO 2 emissions, constitute the main challenge that most European cities need to tackle. In Europe the building sector is responsible for nearly 40% of the total energy consumption. Considering the slow rates of constructing new buildings, a lot of attention needs to be paid to the already existing building stock. This paper presents some of the major projects carried out in Europe and their achievements regarding the integration of innovative technologies and use of different sources of renewable energy in existing buildings. Special attention has been paid to projects targeting historic buildings, since their significant cultural and historic values make their refurbishment and retrofitting process more complex. [ABSTRACT FROM AUTHOR]

The efficient use of energy is a priority when a technology migration plan is being executed. Several factors must be taken into account in order to achieve this goal. In this paper the migration from liquefied petroleum gas based cookers to electric induction cookers is analyzed, emphasizing on the selection of the best material to produce the cookware suitable for induction cookers in terms of energy saving and performance. To accomplish this study, several tests have been performed in three kind of pots made of different materials: stainless steel, cast iron and aluminium. These tests have allowed to evaluate some material properties as rust resistance, structural stability of pot bottom under thermal impact conditions, energy efficiency measurements in different body cookware materials, energy efficiency with different distances between induction zone and pot bottom, relation between energy efficiency and initial measurements of concavity/convexity and energy efficiency before and after thermal impact conditions. After completing this research, it has been found that the enameled cast iron and the stainless steel present higher efficiency in the same stove. [ABSTRACT FROM AUTHOR]

In data centers, about 40% of the total energy is consumed for cooling the IT equipment. Cooling costs are thus one of the major contributors to the total electricity bill of large data centers. This paper studies two factors affecting data center cooling energy consumption, namely air flow management and data center location selection. A unique rack layout with a vertically cooling air flow is proposed. Two cooling systems, computer room air conditioning (CRAC) cooling system and airside economizer (ASE), have been studied. Based on these two cooling systems, four cities have been selected from the worldwide data center locations. A number of energy efficiency metrics are explored for data center cooling, such as power usage effectiveness (PUE), coefficient of performance (COP) and chiller hours. By analyzing the effects of chiller hours and economizer hours, comparative economic results of cooling power consumption are provided in both systems. The results show that the cooling efficiency and operating costs vary significantly with different climate conditions, energy prices and cooling technologies. As climate condition is the major factor which affects the airside economizer, employing the airside economizer in the cold climate yields much lower energy consumption and operation costs. [ABSTRACT FROM AUTHOR]

More than 1000 cities in the United States have signed the Mayor's Climate Protection Agreement, yet few have created comprehensive estimates of their energy consumption and carbon emissions footprints. In this paper, we provide estimates of both of these measures for residential and commercial buildings in the 100 largest metropolitan areas in the U.S. over the 2000-2010 period. This tracks the progress towards sustainable development in major urban areas nationally, identifying leaders and laggards, as well as opportunities for improvement. This research also offers real-world policy relevance for energy efficiency efforts in the urban areas where the vast majority of U.S. GDP is produced. [ABSTRACT FROM AUTHOR]

Energy demand imputable to buildings corresponds to around 40% of the total in most of the developed countries, showing the great potential in this field to propose and implement effective strategies for energy saving and environmental sustainability. Additionally, urban areas are the most impacted zones by anthropogenic sources and they are often affected by local climate phenomena such as urban heat islands. In this view, several measures to mitigate this effects and to save energy in constructions are dealt with the implementation of cool materials for roofs and urban paving. Since the majority of cities in Europe is characterized by traditional architectures in residential buildings, the implementation of white cool coatings is not feasible and new solutions are being proposed. In particular, starting from previous works of the authors about the development and continuous monitoring of cool clay tiles, this paper deals with the thermal analysis of low-visual-impact cool tiles in single family residential buildings with varying climate conditions (i.e. latitude) in Europe, from hot subtropical semi-arid climate (Tripoli) to oceanic climate (Munich). A calibrated and validated simulation model by mean of experimental in-lab and in-field measurements, has been used for studying the thermal effect of the proposed clay tiles. The analysis shows how the clay tile has a promising potential to decrease the indoor overheating in all the climate conditions, with relatively low penalties in winter even in the coldest areas. [ABSTRACT FROM AUTHOR]

The building sector is a large consumer of the world's energy and is responsible for 40% of the European Union's (EU) total final energy consumption. The most effective and efficient method to reduce energy consumption of buildings is to retrofit existing buildings with more energy efficient facilities. This paper presents a multi-objective optimization model for building envelope retrofit planning which aims at maximizing energy savings and economic benefits with given investment budget. It also takes thermal comfort and life-cycle impact into consideration. Results from application to the retrofit planning of a 70 years old family house show that energy consumption can be reduced effectively by the presented model. [ABSTRACT FROM AUTHOR]

Deep underground mining is highly energy intensive due to the need to overcome high pressure rise required by ventilation fans, high cooling load in summer due to rise in rock temperature and the auto-compression effect, and heating requirement in winter. Rising energy costs have led the mining industry to look for alternatives in energy-efficient systems to reduce the operating costs as well as to reduce the carbon footprint. This paper addresses the challenge by utilizing naturally available renewable energy source from seasonal cycle for heating and cooling of underground mines: heat in the summer is stored in the rock-pit to be used for heating in winter, and the “cold” energy in winter is captured and is stored in the rock-pit for cooling during summer. A three-dimensional unsteady local thermal non-equilibrium (LTNE) model is developed to evaluate thermal storage and heat transfer between ventilation air and rock-pit (large broken rock mass). The results suggest that the seasonal thermal energy storage (Se-TES) of rock-pit is able to assist thermal management in underground mine and to reduce energy consumption for winter heating and summer cooling. The ventilation air temperature is about 15 to 20 ˚C higher/lower as compared to ambient temperature in winter/summer, respectively. Clearly, this shows potential application of large scale Se-TES in mining industry. [ABSTRACT FROM AUTHOR]

Energy efficiency in the demand side is considered one of the cheapest ways to achieve reductions in Green House Gases emission, as well as to avoid heavy investments in production, transmission and distribution of electricity. In the context of the Emirate of Abu Dhabi, UAE, where buildings (residential, office, retail and villas) consume about 87% of the electricity, most of which is devoted to indoor air-conditioning, energy efficiency has a huge potential for development. Under the current political/economical scenario, a series of measures to diversify the economy and attract expatriates are in place. These include heavy subsidies on retail electricity prices—which has the side-effect of limiting the economic feasibility of investments in energy efficiency. In this study, a series of building retrofits were tested on a model of the average office building in the Emirate. The best performing retrofit was identified to be the chiller's Coefficient of Performance (COP) improvements, having the lowest cost/benefit ratio and resulting in an overall annual electricity savings of around 12%. Under the current subsidized electricity price, investments in energy efficiency of existing buildings are not attractive for the owner-consumer, as over the lifecycle of the measure, the return on investment is low or negative. In this paper we attempt to assess the applicability, in the Emirate of Abu Dhabi, of energy saving obligations and tradable white certificates as a mechanism to enable investment in demand-side energy efficiency and achieving average investment returns of 7% over a 25 years horizon. The application of white certificates can enable the market of energy efficiency to develop in the Emirate. The economic return of applying a chiller retrofit under the studied white certificate scenario avoids the increase of 17% of current electricity prices. [ABSTRACT FROM AUTHOR]

In this paper, both energy efficiency and environmental efficiency of coal-fired power units are studied based on the non-parametric data envelopment analysis method (DEA). Compared with energy efficiency, the emission of SO 2 and NO x are taken into consideration for the environmental efficiency. The ST model is employed to calculate pure technical efficiency. And the strong disposability model is used to calculate the environmental efficiency. Analysis and comparison for energy and environmental efficiency are conducted. By comparing the influence of ownership factor on these two kinds of efficiency, it can be found that the China Guodian Corporation ranks the first in both the energy and environmental efficiency. China Datang Corporation ranks the third in energy efficiency while ranks the last one in environmental efficiency. [ABSTRACT FROM AUTHOR]

The shipping industry is focusing more and more on reducing fuel consumption and greenhouse gas emissions. A non-negligible amount of fuel is consumed while ships are in port, waiting for loading or unloading, for heating up accommodation spaces and fuel tanks, while when at sea waste heat from engines exhaust is under-used because of low demand. In this paper we propose the use of thermal energy storage as a solution for the mismatch between heat availability and demand. A simplified system is proposed and the influence of design parameters (storage size, heat exchangers surface, secondary fluid mass flow rate, storage temperature) on the performance of the system is analyzed. The results of the application of a thermal energy storage system to a case study ship show that the installation of a storage tank of 1000 m 3 could reduce the fuel consumption from the boilers by 80%, which would lead to yearly savings of 268,000 USD. This preliminary analysis shows that there is potential of both economic and environmental benefits from the application of thermal energy storage to merchant vessels. [ABSTRACT FROM AUTHOR]

Increasing the building sector's energy efficiency while reducing CO 2 emissions, constitute the main challenge that most European cities need to tackle. In Europe the building sector is responsible for nearly 40% of the total energy consumption. Considering the slow rates of constructing new buildings, a lot of attention needs to be paid to the already existing building stock. This paper presents some of the major projects carried out in Europe and their achievements regarding the integration of innovative technologies and use of different sources of renewable energy in existing buildings. Special attention has been paid to projects targeting historic buildings, since their significant cultural and historic values make their refurbishment and retrofitting process more complex. [ABSTRACT FROM AUTHOR]

The number of tall buildings is increasing as a result of the advances in construction technologies and the rising land prices. These buildings are characterised by their high energy consumption compared to other building types as they rely intensively on mechanical HVAC systems due to the extreme weather conditions associated with the increase in height. However, they present a great opportunity for energy savings. In recent years, it has been noticed the increasing interest in geometry and form of tall buildings, as a result of the evolution of parametric modelling and 3D visualisation tools, on the expense of the environmental aspect. This paper discusses factors affecting the energy consumption in the tall buildings. Through an extensive analysis of Literature, active and passive energy efficient strategies adopted in tall building at various building stages are identified. In addition, the role of architectural design parameters, such as building form, orientation and envelope on the tall building energy performance are highlighted. Finally, a set of guidelines and environmental design strategies to be considered in different phases in order to achieve energy-efficient tall buildings are proposed. These strategies have been categorised into four stages namely early design, conceptualisation, and documentation and operational. A 3D modelling approach was used to visualise and illustrate the proposed strategies in different stages. [ABSTRACT FROM AUTHOR]

The efficient use of energy is a priority when a technology migration plan is being executed. Several factors must be taken into account in order to achieve this goal. In this paper the migration from liquefied petroleum gas based cookers to electric induction cookers is analyzed, emphasizing on the selection of the best material to produce the cookware suitable for induction cookers in terms of energy saving and performance. To accomplish this study, several tests have been performed in three kind of pots made of different materials: stainless steel, cast iron and aluminium. These tests have allowed to evaluate some material properties as rust resistance, structural stability of pot bottom under thermal impact conditions, energy efficiency measurements in different body cookware materials, energy efficiency with different distances between induction zone and pot bottom, relation between energy efficiency and initial measurements of concavity/convexity and energy efficiency before and after thermal impact conditions. After completing this research, it has been found that the enameled cast iron and the stainless steel present higher efficiency in the same stove. [ABSTRACT FROM AUTHOR]

In data centers, about 40% of the total energy is consumed for cooling the IT equipment. Cooling costs are thus one of the major contributors to the total electricity bill of large data centers. This paper studies two factors affecting data center cooling energy consumption, namely air flow management and data center location selection. A unique rack layout with a vertically cooling air flow is proposed. Two cooling systems, computer room air conditioning (CRAC) cooling system and airside economizer (ASE), have been studied. Based on these two cooling systems, four cities have been selected from the worldwide data center locations. A number of energy efficiency metrics are explored for data center cooling, such as power usage effectiveness (PUE), coefficient of performance (COP) and chiller hours. By analyzing the effects of chiller hours and economizer hours, comparative economic results of cooling power consumption are provided in both systems. The results show that the cooling efficiency and operating costs vary significantly with different climate conditions, energy prices and cooling technologies. As climate condition is the major factor which affects the airside economizer, employing the airside economizer in the cold climate yields much lower energy consumption and operation costs. [ABSTRACT FROM AUTHOR]

More than 1000 cities in the United States have signed the Mayor's Climate Protection Agreement, yet few have created comprehensive estimates of their energy consumption and carbon emissions footprints. In this paper, we provide estimates of both of these measures for residential and commercial buildings in the 100 largest metropolitan areas in the U.S. over the 2000-2010 period. This tracks the progress towards sustainable development in major urban areas nationally, identifying leaders and laggards, as well as opportunities for improvement. This research also offers real-world policy relevance for energy efficiency efforts in the urban areas where the vast majority of U.S. GDP is produced. [ABSTRACT FROM AUTHOR]

During the study two buildings have been analysed, both belong to 103 series buildings. The main objective of the work is to assess the efficiency of mechanical ventilation systems with heat recovery in renovated multi-family residential buildings. A comparison with natural ventilation systems is included. The paper focuses on data collection and analysis in two newly renovated buildings; both for energy efficiency and indoor air quality. It also shows one of the ways to solve space and low ceiling problems in existing multi-story apartment buildings by integrating supply air ducts in the insulation layer of the building facade. [ABSTRACT FROM AUTHOR]

The paper describes the government and municipalities’ buildings, policy instruments and financial feasibility analysis, created system dynamics model and use of parameters to change the behaviour of the system. The aim of this research is to outline the dynamics under the market of energy efficiency in both municipality and state owned buildings. A system dynamics approach has been used to show short and medium term impact on municipal and government owned building energy efficiency and the changes which are made by using policy instruments. By the year 2016 the estimated savings set in Latvian energy efficiency action plans will not be reached but by 2020, these goals will be achieved. [ABSTRACT FROM AUTHOR]

Mauritius has a long tradition of using cogeneration systems for electricity generation. Bagasse, a by-product of sugar cane is burnt in high temperature and pressure boilers to produce superheated steam to be used for combined heat and power generation. Steam is fed in condensing extraction steam turbine coupled with an alternator to produce electricity and the exit low pressure steam of the turbine is used for the processing of sugar with flexibility to be employed also in distillery and refinery activities. Multi-criteria analysis of such bio-refinery inputs and outputs is conducted considering Energy, Engineering, Economic, Environmental and Ethical dimensions like sustainability, equity and democratization of the energy sector. Due to the reduction of price obtained for the sale of sugar to the European Union, the sugar industry has to re-engineer itself to move towards the flexi-factory concept for its survival. Production of high value-added refined sugar/special sugars, dehydrated ethanol for transport and power use and green electricity are constrained by a host of factors from climatic conditions to the price of sugar on the world market through the grid power costs itself dependent on world oil and coal prices. Environmental standards are also to be considered. The aim of this paper is to optimize the cogenerated energy systems of the cane flexi-factory by a holistic energy systems analysis. Actual parameters of a flexi-factory are used to calculate the energy efficiency of each components parts of the system as well as social, economic and environmental benefits. Policy implications crucial to the future viability of such complex energy systems; these are fully discussed in relation to national and international objectives. [ABSTRACT FROM AUTHOR]

Building envelope is widely recognized as a key factor that influences building energy consumption. However, the bulk of passive envelope research is based in cold climates. It remains largely unknown how building envelope design measures are selected and to what extent building energy efficiency can be improved in hot-humid climate. This paper explores the energy-efficient envelope design measures through the combination of understanding the environment, identifying potential measures, setting up models, running analysis, and making design decisions. The findings should inform building envelope design decisions and support building energy performance analysis in hot-humid climate. [ABSTRACT FROM AUTHOR]

This paper analyzes the results of a quasi-experimental design with 500 households in a target group (with smart meters) and 500 – in a control group (without smart meters) in Latvia. Lorenz curves are used to quantify the reduction in electricity consumption and to study the re-distribution of energy allocation due to roll-out of smart meters. Results on energy distribution for the target group suggest that the reduction of electricity consumption play a minor role on energy equity in a short-term, but effect is growing over last months of the study. These results could be explained by the hypothesis that investments in energy efficient lighting and home appliances take time. [ABSTRACT FROM AUTHOR]

The paper analyses the most suitable temperature regime of district heating (DH) systems for a new building and exiting dwelling building area depending on end-user thermal energy consumption. Research methodology includes algorithm with several modules. The multi-criteria analysis is used for evaluating of different DH systems and finding of optimal solution of 12 scenarios by taking into account different criteria. The TOPSIS and PROMETHEE tools are integrated to find the optimal solutions. The DH systems multi-criteria analysis is tested for climate conditions in Baltic States. The results show that optimal solutions for standard buildings are temperature regime of 90/60 or 60/30 and boiler house fuelled by wood chips. Temperature regime 60/30 in case of the energy-efficient building scenario also is close to the best solution. [ABSTRACT FROM AUTHOR]