Demand Aggregation as a Strategy for Untapping Buildings’ Energy Renovation Potential: Diagnosis and Prioritization Methodology and Case Study from the Basque Country

Energy renovation of post-World War II private multifamily residential buildings has been identified to have a great deal of energy-saving potential but faces a great challenge across Europe, and especially in South Europe, due to fragmented property structures and longer return periods in energy efficiency investments. However, there is great deal of potential in activating demand aggregation in areas with homogeneous typologies. Local authorities play a key role in leading district-scale renovation but lack adequate methods for analysing and prioritizing areas from an integrated perspective, including social aspects. The methodology presented in this paper aims to support local authorities by providing a tool for the diagnosis and prioritization of homogeneous groups of residential buildings to address their renovation based on an analysis of their needs and opportunity factors. First, the methodology sets the universe of analysis; second, based on indicators, it provides comparative information within the municipality, which leads to a prioritization of areas for building renovations according to the state of the building and to the socio-economic profile of the residents; lastly, a detailed diagnosis of selected groups is performed, providing information to design the Renovation Action Plans accordingly. The application of the methodology in Basauri is presented in this paper.

PERSPECTIVES FOR A WIND ASSISTED SHIP PROPULSION

For three different wind propulsion technologies, the energy saving potential of sea going cargo vessels are discussed: a kite, a Flettner rotor and a Dynarig-sail. The energy saving potential can be increased significantly if the route can be optimized when using a wind assisted ship propulsion. The increase of travelling time due to a route adoption is within the frame of the commonly accepted uncertainty in supply chains and can be limited or adjusted in the route optimization software as a parameter. The calculated saving potential depends on several parameters: the considered wind propulsion system, the route, the kind of ship (bulker, multipurpose carrier, tanker), as well as the ship speed and the weather. The cost-effectiveness of the installation of a wind propulsion system strongly depends on the fuel price, the ship speed and the international policy concerning the ship emissions.

Energy saving potential of occupancy sensors in intermittent-use space types.

<p>For decades, studies have been suggesting the idea of occupancy sensors in intermittent use spaces for energy savings. This work investigates the potential energy savings of occupancy sensors in hallways, stairwells, seminar rooms and lavatories of an education building. Lighting is one of the largest consumers of energy in the building industry and these space types are often fully illuminated for long periods of vacancy. Lighting is for the user, not the building. Discussions centre around light use habits, energy saving behaviours and sensor technology such as time delay and daylight sensors. The experiment uses wireless light sensors and PIR sensors to measure light energy use and occupant use of 20 intermittent use spaces. A user survey was planned to run alongside the experiment to investigate user perceptions of changes in lighting but was discontinued due to unresolved software issues. Results of the experiment encouraged the use of occupancy sensors in intermittent use spaces. Lavatories attained highest energy saving potential 54%, seminar rooms highest annual cost savings per fitting $15.47 and highest annual energy savings 482kWh and hallways calculated the quickest payback of 8.6 years. Hallways, stairwells, seminar rooms and lavatories all offer potential for energy savings, supporting the theoretical ideas and success of occupancy sensors in intermittent use spaces.</p>

Energy saving potential of occupancy sensors in intermittent-use space types.

<p>For decades, studies have been suggesting the idea of occupancy sensors in intermittent use spaces for energy savings. This work investigates the potential energy savings of occupancy sensors in hallways, stairwells, seminar rooms and lavatories of an education building. Lighting is one of the largest consumers of energy in the building industry and these space types are often fully illuminated for long periods of vacancy. Lighting is for the user, not the building. Discussions centre around light use habits, energy saving behaviours and sensor technology such as time delay and daylight sensors. The experiment uses wireless light sensors and PIR sensors to measure light energy use and occupant use of 20 intermittent use spaces. A user survey was planned to run alongside the experiment to investigate user perceptions of changes in lighting but was discontinued due to unresolved software issues. Results of the experiment encouraged the use of occupancy sensors in intermittent use spaces. Lavatories attained highest energy saving potential 54%, seminar rooms highest annual cost savings per fitting $15.47 and highest annual energy savings 482kWh and hallways calculated the quickest payback of 8.6 years. Hallways, stairwells, seminar rooms and lavatories all offer potential for energy savings, supporting the theoretical ideas and success of occupancy sensors in intermittent use spaces.</p>

INTEGRATION OF DAYLIGHT WITH ELECTRIC LIGHTING IN COMMERCIAL BUILDINGS: A CASE STUDY FROM NEPAL

Daylight attributes to the aggregate of direct and indirect lights originating from the sun during the daytime. Integrating daylight with electrical lighting can serve as a means to lessen electricity costs for buildings. Geographic location and weather conditions facilitate most of the areas of Nepal to receive on average 12 hours of daylight and have huge energy-saving potential. However, the integration of daylight has not been admitted in the building code of Nepal. Moreover, contemporary architectural design lacks employment of techniques illustrated by illumination engineering to integrate daylight. This study analyses the plausibility and benefits of integrating daylight with electric light for a typical commercial building of Nepal employing the DIALux model and simulation. Simulation integrating energy-efficient electric light and daylight was done to observe illumination levels and light power density. For daylight performance, year-round conditions were observed for three different sky types. Modification of building architecture to integrate daylighting components was also studied. In the later part of the study, analysis was done to observe energy-saving potential and financial benefits. Results designated the plausibility of blending daylight with electrical lighting in the building for all-sky conditions. Extensive energy thrift was observed and was higher with added daylight components. Recommendations of the study to blend light sources and incorporation of daylight components are attainable with current technology and trend in Nepal with accompanying benefits of energy-saving, reduced operation, and reduced maintenance cost.

Method for determining the Z2-energy saving potential objects of the regional electrotechnical complex

В статье представлена методика определения Z2-потенциала энергосбережения объектов регионального электротехнического комплекса. Актуальность её разработки обоснована необходимостью повышения энергосбережения во всех отраслях региона для обеспечения экономической стабильности. Реализация этапов энергосбережения предполагает три направления: снижение и полезное использование энергетических потерь, модернизация и разработка электроустановок, использующих современные цифровые технологии и реализация научно обоснованных методов, моделей и методик, позволяющих существенно повысить энергоэффективность объектов региона. В рамках третьего направления была разработана третья методика. Теоретической основой методики является векторный ранговый анализ. Она включает в себя три расчётных блока: подготовки данных, расчёта добавочного ресурса и определения Z2-потенциала энергосбережения. Новизна методики заключается в реализации впервые разработанного математического аппарата на основе векторного рангового анализа, позволяющего при определении потенциала энергосбережения учесть внешнее управляющее воздействие вышестоящей энергосистемы. Это позволяет осуществить большую экономию денежных средств, которые расходуются на потери электроэнергии с целью модернизации электроустановок, внедрения новых технологий или премирование персонала. The article presents a methodology for determining the Z2-energy saving potential of objects of the regional electrical complex. The relevance of its development is justified by the need to increase energy conservation in all sectors of the region to ensure economic stability. The implementation of energy saving stages involves three directions: reduction and useful use of energy resources, modernization and development of electrical installations using modern digital technologies and the implementation of scientifically based methods, models and techniques that can significantly increase the energy efficiency of the region's facilities. Within the framework of the third direction, a third methodology was developed. The theoretical basis of the methodology is vector rank analysis. It includes three calculation blocks: data preparation, calculation of additional resource and determination of Z2-energy saving potential. The novelty of the technique lies in the implementation of a mathematical apparatus developed for the first time on the basis of vector rank analysis, which allows taking into account the external control influence of a higher power system when determining the energy saving potential. This makes it possible to save a lot of money that is spent on electricity losses in order to modernize electrical installations, introduce new technologies or award personnel.