Building energy information systems: synthesis of costs,savings, and best-practice uses

Building energy information systems (EIS) are a powerful customer-facing monitoring and analytical technology that can enable up to 20 % site energy savings for buildings. Few technologies are as heavily marketed, but in spite of their potential, EIS remain an underadopted emerging technology. One reason is the lack of information on purchase costs and associated energy savings. While insightful, the growing body of individual case studies has not provided industry the information needed to establish the business case for investment. Vastly different energy and economic metrics prevent generalizable conclusions. This paper addresses three common questions concerning EIS use: what are the costs, what have users saved, and which best practices drive deeper savings? We present a large-scale assessment of the value proposition for EIS use based on data from over two-dozen organizations. Participants achieved year-over-year median site and portfolio savings of 17 and 8 %, respectively; they reported that this performance would not have been possible without the EIS. The median 5-year cost of EIS software ownership (up-front and ongoing costs) was calculated to be $1800 per monitoring point (kilowatt meter points were most common), with a median portfolio-wide implementation size of approximately 200 points. In this paper, we present an analysis of the relationship between key implementation factors and achieved energy reductions. Extent of efficiency projects, building energy performance prior to EIS installation, depth of metering, and duration of EIS were strongly correlated with greater savings. We also identify the best practices use of EIS associated with greater energy savings.     

Energy conservation in fossil-fuel-fired systems: Three case studies

This paper reports the results of energy analysis of oil- and coal-fired systems in a sodium silicate industry, in a mechanized bakery and in silk filatures. In all, seven systems (three oil-fired and four coal-fired units) were evaluated and energy conservation measures were suggested. It is shown that in most cases, the fuel consumption can be reduced by over half. The recommendations for fuel savings and mathematical simulations are valid for similar systems elsewhere.     

浅谈建筑能耗模拟与建筑节能

建筑能耗模拟是建筑节能设计的重要技术手段。本文介绍了建筑能耗模拟的原理，模拟软件及其特点，列举了建筑能耗模拟的应用。     

Photochemical energy conversion studies in systems containing methylene blue

The behaviour of photogalvanic cells containing methylene blue with various reducing agents has been examined. Appreciable potentials and currents have been detected. the power conversion efficiency of an EDTA-methylene blue photogalvanic cell has been estimated to be ±0.04 per cent. the storage of light energy in iron-methylene blue and EDTA-methylene blue systems has been studied.     

Design and analysis of hybrid energy systems: The Brazilian Antarctic Station case

This paper presents the design and analysis of a hybrid energy system for an Antarctic Station. The research considered the constraints of the extreme climate, the logistics limitations and the technical assets of the Brazilian Antarctic Station. The thermal and electrical annual profiles of the Station, the spreadsheets of the organic solid waste, and the local measured data of wind and sun were investigated. The application of anaerobic digestion, combined heat and power generation, use of photovoltaic panels and wind turbines were analysed. In the renewables analyses, 25 years of local climatic data were assessed. The influences of air density, temperature and ground reflectance on the renewable generation were also investigated. In order to assess potentials hybrid energy systems for the Brazilian Antarctic Station, possible topologies were organized in groups and then analysed by consumption, performance and feasibility. The methodology supported the identification of an efficient and feasible energy system for the Brazilian Station. The proposed system reached 37% of fuel saves considering the original demand profile of the Station. This work adopted the liter of oil as a currency, thus in any future time the results can be used for financial studies.     

Application of geographical information systems to rural electrification with renewable energy sources

This paper approaches one of the main problems of rural electrification: the choice of the most appropriate technology for each case. The main objective of this project is to apply Geographical Information Systems (GIS) to divide the research zone into areas in that are more appropriate for either conventional or renewable technologies. The approaches for choosing among the different technologies are usually technical and economic; these may be jointly considered by the leveling electric cost (LEC). Determination of the LEC is a complex task that requires knowledge of the capacity factor. This paper shows the conclusions of the technical and economic parameter analysis involved in the determination of the LEC for each technology. This analysis has allowed us to carry out proposals of improvement in the methodology of the GIS of rural electrification. The resulting GIS has been verified in the municipality of Lorca (Murcia, Spain).     

Unintended anchors: Building rating systems and energy performance goals for U.S. buildings

In the U.S., where buildings account for 40% of energy use, commercial buildings use more energy per unit area than ever before. However, exemplary buildings demonstrate the feasibility of much better energy performance at no additional first cost. This research examines one possible explanation for this inconsistency. The aim is to investigate whether the anchoring bias, which refers to our tendency to gravitate towards a pre-defined standard regardless of its relevance, influences energy performance goals in building design. The scope examines professionals who help set energy performance goals for U.S. buildings. Prior to being asked to set an energy performance goal, these professionals were randomly directed to one of three series of questions. One series set an anchor of 90% energy reduction beyond standard practice, one set a 30% anchor, and one set no anchor. Respondents exposed to the 90% anchor, and respondents exposed to no anchor at all, set higher energy performance goals than respondents exposed to the 30% anchor. These results suggest that building rating systems that only reward incremental energy improvements may inadvertently create anchors, thereby discouraging more advanced energy performance goals and inhibiting energy performance that is technically and economically feasible.     

Evaluation of region-specific residential energy systems for GHG reductions: Case studies in Canadian cities

This study estimates energy use and greenhouse gas (GHG) emissions associated with operations of alternative residential energy systems. In case studies, the same detached four-bedroom house built in accordance with R2000 standards is studied in five Canadian cities with different climate and electricity mix. Conventional energy systems and alternatives using three technologies, namely ground source heat pumps (GSHPs), photovoltaics, and energy-efficient appliances; and their combinations are investigated. The results show that using a GSHP in Calgary may increase overall GHG emissions, as electricity to drive the pump is primarily produced in coal-fired power stations. Using photovoltaics to generate electricity from carbon-free sources or energy-efficient appliances to reduce electricity demands result in almost no GHG reductions in Montreal and Vancouver, where over 90% of electricity comes from hydro power. The results also show that the use of photovoltaics in combination with GSHPs in Ottawa and Toronto, or with energy-efficient appliances in Calgary, can lead to more GHG reductions, compared to the use of a single technology. As a result, while climate affects energy use to some degree, local sources of electricity may have a greater impact on overall GHG emissions, which is an important measure of environmental impacts.     

Modelling of water–energy systems. The case of desalination

The primary aim of this work is to assess the long-term sustainability of the desalination technology in alleviating the global freshwater crisis. The Canary Islands (Spain) have a well-established experience in desalination and the Island of Lanzarote –whose water supply is entirely dependent upon this technology—is taken as an illustrative case study. Analytical information obtained from the Material and Energy Flow Accounts of Lanzarote's desalination metabolism are fed into a model developed with the Vensim software to allow future trends, prediction and evaluate different scenarios. To conclude, the main environmental impacts of the desalination technology are addressed and some socially induced factors leading to unsustainable water management are briefly discussed.     

Strategic analysis methodology for energy systems with remote island case study

A strategic analysis methodology is presented for adaptive energy systems engineering to realize an optimal level of service in the context of a community's social, economic, and environmental position. The groundwork stage involves characterizing the social context, assessing available energy resources, identifying environmental issues, setting eco-resource limits, and quantifying socio-economic constraints for a given region. A spectrum of development options is then constructed according to the range of energy service levels identified for the sector under study. A spectrum of conceptual energy systems is generated and infrastructure investments and resource use are modeled. The outcome is a matrix of energy system investment possibilities for the range of energy demand levels reflecting the values, ideas, and expectations expressed by the community. These models are then used to assess technical feasibility and economic, environmental and social risk. The result is an easily understood graphical depiction of local aspirations, investment options, and risks which clearly differentiates development opportunities from non-viable concepts. The approach was applied to a case study on Rotuma, an isolated Pacific Island. The case study results show a clear development opportunity space for Rotuma where desired energy services are in balance with investment sources, resource availability, and environmental constraints.     

The role of hydrogen in high wind energy penetration electricity systems: The Irish case

The deployment of wind energy is constrained by wind uncontrollability, which poses operational problems on the electricity supply system at high penetration levels, lessening the value of wind-generated electricity to a significant extent. This paper studies the viability of hydrogen production via electrolysis using wind power that cannot be easily accommodated on the system. The potential benefits of hydrogen and its role in enabling a large penetration of wind energy are assessed, within the context of the enormous wind energy resource in Ireland. The exploitation of this wind resource may in the future give rise to significant amounts of surplus wind electricity, which could be used to produce hydrogen, the zero-emissions fuel that many experts believe will eventually replace fossil fuels in the transport sector. In this paper the operation of a wind powered hydrogen production system is simulated and optimised. The results reveal that, even allowing for significant cost-reductions in electrolyser and associated balance-of-plant equipment, low average surplus wind electricity cost and a high hydrogen market price are also necessary to achieve the economic viability of the technology. These conditions would facilitate the installation of electrolysis units of sufficient capacity to allow an appreciable increase in installed wind power in Ireland. The simulation model was also used to determine the CO₂ abatement potential associated with the wind energy/hydrogen production.     

EnerGis: A geographical information based system for the evaluation of integrated energy conversion systems in urban areas

A geographical information system has been developed to model the energy requirements of an urban area. The purpose of the platform is to model with sufficient detail the energy services requirements of a given geographical area in order to allow the evaluation of the integration of advanced integrated energy conversion systems. This tool is used to study the emergence of more efficient cities that realize energy efficiency measures, integrate energy efficient conversion technologies and promote the use of endogenous renewable energy. The model is illustrated with case studies for the energetic planning of the Geneva district (Switzerland).     

Uncertainties in the design and operation of distributed energy resources: The case of micro-CHP systems

Large-scale diffusion of distributed energy resources (DERs) will have a profound impact on electricity infrastructure functioning: it will bring radical changes to the traditional model of generation and supply as well as to the business model of the energy industry. DERs comprise distributed power generators, distributed energy storages and controllable loads. There are, however, many uncertainties that influence the design and operation of DERs. This paper clarifies these uncertainties by proposing and applying a comprehensive framework for uncertainty analysis. We thereby adopt an integrated approach that considers not only the technical, but also the economic and institutional uncertainties. A delineation of the work is a focus on residential DERs and on micro-CHP systems specifically. After the proposed framework for uncertainty analysis is explained the uncertainties pertaining to the design and operation of residential DERs and micro-CHP systems are identified. In a case study system a selection of the uncertainties are quantitatively analysed. The case study system consists of a household that intelligently applies a micro-CHP unit in conjunction with energy storages and that interacts with its energy supplier. With a sensitivity analysis of the system model the salient impacts of the uncertainties on system behaviour and performance are enunciated.     

Local acceptance of wind energy: Factors of success identified in French and German case studies

The objective of this paper is to identify and analyse factors that are important for winning acceptance of wind-energy parks on the local level. The developers of wind-energy parks need to know how to manage “social acceptance” at the different stages of planning, realisation and operation. Five case studies in France and Germany focused on factors of success in developing a wind-energy project on a given site and illuminated how policy frameworks influence local acceptance. Our hypothesis is that these factors fall into two categories: institutional conditions, such as economic incentives and regulations; and site-specific conditions (territorial factors), such as the local economy, the local geography, local actors, and the actual on-site planning process (project management).     

Building energy research in Hong Kong: A review

Hong Kong is located in a typical subtropical region. The buildings in Hong Kong are subjected to high cooling demands for their air-conditioning systems throughout most of the year, and their contribution toward the total energy consumption is about 40%. Therefore, energy efficiency in buildings is essential to reduce the global energy use and improve the local environmental sustainability. This paper provides an overall review of the building energy research and efforts in Hong Kong over the last decade. Various aspects and energy saving measures, including energy policy, energy audit, design, control, diagnosis, building performance evaluation and renewable energy systems, studied or used to enhance the energy efficiency in buildings are reviewed. A brief introduction of the Hong Kong Building Energy Codes (BEC) and Hong Kong Building Environmental Assessment Method (HK-BEAM) are also provided to present the efforts of the local government and community on energy efficiency in buildings. This review aims at providing building researchers and practitioners a better understanding of buildings energy saving opportunities and approaches in cities particularly in subtropical regions and taking further proper actions to promote buildings energy efficiency and conservation.     

Involving the user : Community based management of solar home systems in Indonesia

Taking existing technologies simply off the shelf and handing them over to users might in the beginning satisfy stakeholders and users involved in a rural electrification project but the likelihood of failure and disappointment is very high. Pitfalls are well known and have led to a slow down of entrepreneurial initiatives and market development. In Indonesia with its long history of harnessing new and renewable energy technologies (NRE), participatory development is not common for decentralized rural electrification (RE) schemes. Although electrification by means of Solar Home Systems (SHS) has a long tradition throughout the archipelago, community-based management has long been neglected and hence projects have been prone to failure. Implementing SHS in a sustainable way is still far from routine business and requires competent resources, interdisciplinary know-how if the scheme should last long and public knowledge about the benefits of electricity utilization. In this article Claus Dauselt, describes the Indonesian SHS experience and aspects important for sustainable, decentralized rural electrification in particular the need for community involvement in the project right from the start.     

GIS-based environmental assessment of wind energy systems for spatial planning: A case study from Western Turkey

Increasing population and life standards causes fossil fuel consumption to increase. Due to this increasing consumption, fossil fuels are being depleted rapidly. In addition to rapid exhaustion, another important problem associated with fossil fuels is that their consumption has major negative impacts on the environment. Therefore, many countries around the world have included renewable energy systems (RES) in their future energy plans so that they can produce reliable and environmentally friendly energy. Parallel to this trend, various RES have been identified and recently integrated into the current energy network of Turkey as well. However, it should be recognized that renewable energy resources are not fully environmentally safe. Different RES are associated with different environmental impacts. In planning the future energy development of a country, evaluation of renewable energy resources potentials together with their associated environmental impacts is critical. The aim of this study is to create a decision support system for site selection of wind turbines using Geographic Information System (GIS) tools. Wind energy potential and environmental fitness/acceptability are used as decision criteria for the site selection process. Potential environmental impacts of wind generation are identified in accordance with Turkish legislations and previous studies; and represented as fuzzy objectives of the decision problem. Wind potential map of Turkey generated by General Directorate of Electrical Power Resources Survey and Development is used to identify economically feasible locations in terms of wind energy generation. A study area composed of Usak, Aydin, Denizli, Mugla, and Burdur provinces in Turkey is selected and divided into 250 m × 250 m grids. Each grid represents an alternative location for a wind turbine or group of wind turbines. Fuzzy environmental objectives such as “Acceptable in terms of noise level”, “Acceptable in terms of bird habitat”, “Acceptable in terms of safety and aesthetics” and “Safe in terms of natural reserves” associated with wind turbines are identified based on previous research and each of these objectives are represented by a fuzzy set. Individual satisfaction degree of each of these environmental objectives for each grid is calculated. Then these individual satisfactions are aggregated into an overall satisfaction degree using various aggregator operators such as “and”, “or”, and “order weighted averaging.” Thus, an overall satisfaction degree of all the environmental objectives is obtained for each grid in the study area. A map of environmental fitness is developed in GIS environment by using these overall satisfaction degrees. Then this map is utilized together with the wind potential map of Turkey to identify both potentially and environmentally feasible wind turbine locations within the study area.