Energy demand profile generation with detailed time resolution at an urban district scale: A reference building approach and case study

Because of extensive variations in occupancy patterns around office space environments and their use of electrical equipment, accurate occupants’ behaviour detection is valuable for reducing the building energy demand and carbon emissions. Using the collected occupancy information, building energy management system can automatically adjust the operation of heating, ventilation and air-conditioning (HVAC) systems to meet the actual demands in different conditioned spaces in real-time. Existing and commonly used ‘fixed’ schedules for HVAC systems are not sufficient and cannot adjust based on the dynamic changes in building environments. This study proposes a vision-based occupancy and equipment usage detection method based on deep learning for demand-driven control systems. A model based on region-based convolutional neural network (R-CNN) was developed, trained and deployed to a camera for real-time detection of occupancy activities and equipment usage. Experiments tests within a case study office room suggested an overall accuracy of 97.32% and 80.80%. In order to predict the energy savings that can be attained using the proposed approach, the case study building was simulated. The simulation results revealed that the heat gains could be over or under predicted when using static or fixed profiles. Based on the set conditions, the equipment and occupancy gains were 65.75% and 32.74% lower when using the deep learning approach. Overall, the study showed the capabilities of the proposed approach in detecting and recognising multiple occupants’ activities and equipment usage and providing an alternative to estimate the internal heat emissions.

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Passive Solar Solutions for Buildings: Criteria and Guidelines for a Synergistic Design

Applied Sciences ◽

10.3390/app11010376 ◽

2021 ◽

Vol 11 (1) ◽

pp. 376

Author(s):

Giacomo Cillari ◽

Fabio Fantozzi ◽

Alessandro Franco

Keyword(s):

Energy Demand ◽

Theoretical Background ◽

Environmental Benefits ◽

Passive Systems ◽

Extrinsic Factors ◽

Solar Systems ◽

Final Performance ◽

Passive Solar ◽

Energy Simulations

Passive solar system design is an essential asset in a zero-energy building perspective to reduce heating, cooling, lighting, and ventilation loads. The integration of passive systems in building leads to a reduction of plant operation with considerable environmental benefits. The design can be related to intrinsic and extrinsic factors that influence the final performance in a synergistic way. The aim of this paper is to provide a comprehensive view of the elements that influence passive solar systems by means of an analysis of the theoretical background and the synergistic design of various solutions available. The paper quantifies the potential impact of influencing factors on the final performance and then investigates a case study of an existing public building, analyzing the effects of the integration of different passive systems through energy simulations. General investigation has highlighted that latitude and orientation impact energy saving on average by 3–13 and 6–11 percentage points, respectively. The case study showed that almost 20% of the building energy demand can be saved by means of passive solar systems. A higher contribution is given by mixing direct and indirect solutions, as half of the heating and around 25% of the cooling energy demand can be cut off.

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An aircraft gas chromatograph–mass spectrometer System for Organic Fast Identification Analysis (SOFIA): design, performance and a case study of Asian monsoon pollution outflow

Atmospheric Measurement Techniques ◽

10.5194/amt-10-5089-2017 ◽

2017 ◽

Vol 10 (12) ◽

pp. 5089-5105 ◽

Cited By ~ 6

Author(s):

Efstratios Bourtsoukidis ◽

Frank Helleis ◽

Laura Tomsche ◽

Horst Fischer ◽

Rolf Hofmann ◽

...

Keyword(s):

Time Resolution ◽

Asian Monsoon ◽

Electrical Safety ◽

Back Trajectory ◽

Airborne Measurements ◽

Mixing Ratios ◽

Fast Identification ◽

Chemistry Research ◽

Identification Analysis

Abstract. Volatile organic compounds (VOCs) are important for global air quality and oxidation processes in the troposphere. In addition to ground-based measurements, the chemical evolution of such species during transport can be studied by performing in situ airborne measurements. Generally, aircraft instrumentation needs to be sensitive, robust and sample at higher frequency than ground-based systems while their construction must comply with rigorous mechanical and electrical safety standards. Here, we present a new System for Organic Fast Identification Analysis (SOFIA), which is a custom-built fast gas chromatography–mass spectrometry (GC-MS) system with a time resolution of 2–3 min and the ability to quantify atmospheric mixing ratios of halocarbons (e.g. chloromethanes), hydrocarbons (e.g isoprene), oxygenated VOCs (acetone, propanal, butanone) and aromatics (e.g. benzene, toluene) from sub-ppt to ppb levels. The relatively high time resolution is the result of a novel cryogenic pre-concentration unit which rapidly cools (∼ 6 °C s−1) the sample enrichment traps to −140 °C, and a new chromatographic oven designed for rapid cooling rates (∼ 30 °C s−1) and subsequent thermal stabilization. SOFIA was installed in the High Altitude and Long Range Research Aircraft (HALO) for the Oxidation Mechanism Observations (OMO) campaign in August 2015, aimed at investigating the Asian monsoon pollution outflow in the tropical upper troposphere. In addition to a comprehensive instrument characterization we present an example monsoon plume crossing flight as a case study to demonstrate the instrument capability. Hydrocarbon, halocarbon and oxygenated VOC data from SOFIA are compared with mixing ratios of carbon monoxide (CO) and methane (CH4), used to define the pollution plume. By using excess (ExMR) and normalized excess mixing ratios (NEMRs) the pollution could be attributed to two air masses of distinctly different origin, identified by back-trajectory analysis. This work endorses the use of SOFIA for aircraft operation and demonstrates the value of relatively high-frequency, multicomponent measurements in atmospheric chemistry research.

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Hydrokinetic Energy Opportunity for Rural Electrification in Nigeria

International Journal of Renewable Energy Development ◽

10.14710/ijred.7.2.183-190 ◽

2018 ◽

Vol 7 (2) ◽

pp. 183-190 ◽

Cited By ~ 2

Author(s):

Ogunjuyigbe Ayodeji Samson Olatunji ◽

Ayodele Temitope Raphael ◽

Ibitoye Tahir Yomi

Keyword(s):

Rural Communities ◽

Energy Demand ◽

Optimal Investment ◽

Rural Electrification ◽

Economic Activities ◽

Energy Potential ◽

Ongoing Research ◽

Hydrokinetic Energy ◽

Potential Site

This paper is part of the ongoing research by the Power, Energy, Machine and Drive (PEMD) research group of the Electrical Engineering Department of the University of Ibadan. The paper presents various sites with possible hydrokinetic energy potential in Nigeria with the aim of quantifying their energy potential for rural electrification application. Overview of hydrokinetic technology is also presented with the view of highlighting the opportunities and the challenges of the technology for rural electrification. A case study of using hydrokinetic turbine technology in meeting the energy demand of a proposed civic center in a remote community is demonstrated. Some of the key findings revealed that Nigeria has many untapped hydrokinetic potential site and if adequately harnessed can improve the energy poverty and boost economic activities especially in the isolated and remote rural communities, where adequate river water resource is available. The total estimated untapped hydrokinetic energy potential in Nigeria is 111.15MW with the Northern part of the country having 68.18MW while the Southern part has 42.97MW. The case study shows that harnessing hydrokinetic energy of potential site is promising for rural electrification. This paper is important as it will serve as an initial requirement for optimal investment in hydrokinetic power development in Nigeria.Article History: Received November 16th 2017; Received in revised form April 7th 2018; Accepted April 15th 2018; Available onlineHow to Cite This Article: Olatunji, O.A.S., Raphael, A.T. and Yomi, I.T. (2018) Hydrokinetic Energy Opportunity for Rural Electrification in Nigeria. Int. Journal of Renewable Energy Development, 7(2), 183-190.https://doi.org/10.14710/ijred.7.2.183-190

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ASSESSMENT OF ENERGY PERFORMANCE GAP OF AN OFFICE BUILDING

Mokslas - Lietuvos ateitis ◽

10.3846/mla.2021.15292 ◽

2021 ◽

Vol 13 (0) ◽

pp. 1-6

Author(s):

Rasa Džiugaitė-Tumėnienė ◽

Domas Madeikis

Keyword(s):

Energy Efficiency ◽

Energy Demand ◽

Internal Heat ◽

Energy Performance ◽

Energy Model ◽

Indoor Climate ◽

Performance Gap ◽

Protection Measures ◽

Climate Parameters

The high share of global energy costs to create an indoor climate has been of increasing interest to the global community for several decades and is increasingly the focus of policy. This paper analyses the energy performance gap between actual energy consumption and energy demand obtained during the dynamic energy simulation and building certification. To identify the energy performance gap, an existing office of energy efficiency class B was selected as a case study. The simulation program IDA Indoor Climate and Energy was used to create a dynamic energy model, based on the designed documentation and the actual indoor climate parameters recorded by the building management system. The results of the case study showed that the accuracy and reliability of the results presented by the dynamic energy model of the building directly depend on the assumptions. The correct values of the internal heat gains, indoor climate parameters, human behavior, air quality levels at different times of the day and season, HVAC system operation parameters and operation modes, specific fan powers of ventilation systems, the seasonal energy efficiency of cooling equipment and characteristics of sun protection measures have to be selected.

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Improving Daylight Availability in Heritage Buildings: A Case Study of Below-grade Classrooms in Tehran

Journal of Daylighting ◽

10.15627/jd.2021.9 ◽

2021 ◽

Vol 8 (1) ◽

pp. 120-133

Author(s):

Kamyar Soleimani ◽

◽

Nastaran Abdollahzadeh ◽

Zahra Sadat Zomorodian ◽

◽

...

Keyword(s):

Energy Demand ◽

Critical Issue ◽

Natural Light ◽

Classroom Space ◽

Educational Spaces ◽

Visual Tasks ◽

Heritage Buildings ◽

Heritage Building ◽

Daylight Performance

Refurbished heritage buildings usually lack in meeting the required standards defined for the new function especially when reused as educational buildings. Therefore, they are usually equipped with different post-occupancy retrofit strategies to achieve an acceptable level of environmental quality and energy demand. Daylight quality and the distribution of natural light is a critical issue in educational spaces, given that the low level of illuminance in classrooms can decrease students' performance and disrupt visual tasks. In this study, daylight performance of below-grade south-facing classrooms in a heritage building in Tehran, Iran is investigated by implementing 57 different daylighting retrofit strategies using climate-based daylight simulations, in relation to the metric Useful Daylight Illuminance 300-3000lux (UDI-Autonomous). The research proposes the use of reflectors on the interior ceiling and exterior side of the windows (on the ground) to achieve the highest result possible. Although, applying these two systems individually, can boost the spatial distribution of daylight to 75 % and 71%, respectively, the combination of them provide users with UDI-Autonomous in 99% of the classroom space for more than half of the occupancy time.

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Evaluating the Effect of External Horizontal Fixed Shading Devices’ Geometry on Internal Air Temperature, Daylighting and Energy Demand in Hot Dry Climate. Case Study of Ghardaïa, Algeria

Buildings ◽

10.3390/buildings11080348 ◽

2021 ◽

Vol 11 (8) ◽

pp. 348

Author(s):

Sahar Magri Elouadjeri ◽

Aicha Boussoualim ◽

Hassan Ait Haddou

Keyword(s):

Solar Radiation ◽

Parametric Analysis ◽

Energy Demand ◽

Daylighting Simulation ◽

Simulation Results ◽

Shading Devices ◽

Heating Loads ◽

Shading Device ◽

The City

The present study investigates the effect of fixed external shading devices’ geometry on thermal comfort, daylighting and energy demand for cooling and heating in the hot and dry climate of the city of Ghardaïa (Algeria). A parametric analysis was performed by using three software: RADIANCE 2.0 and DAYSIM 3.1 for daylighting simulation and TRNSYS.17 for thermal dynamic simulation. Three shading device parameters were assessed: the spacing between slats, the tilted angle and the slats installation. The vertical shading angle “VSA” is fixed; it is equal to the optimum shading angle measured for Ghardaïa. The simulation results indicate that fixed external shading devices have a significant impact on decreasing the energy demand for cooling; however, they are unable to reduce the total energy demand since they significantly increase heating loads. It was found that fixed external shading devices remove all risks associated with glare in summer by decreasing illuminance close to the window; however, they do not improve daylighting performance in winter because of glare. We note that even if the vertical shading angle “VSA” was the same for all cases, these did not present the same thermal and luminous behavior. This is mainly due to the amount and the way that the solar radiation penetrates space.

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A time-of-use based electricity price package mechanism in retail market considering consumers’ diversity

E3S Web of Conferences ◽

10.1051/e3sconf/202018202009 ◽

2020 ◽

Vol 182 ◽

pp. 02009

Author(s):

Gang Luo ◽

Yujun He ◽

Chen Zhao ◽

Xuan Zhang ◽

Shaohua Lin ◽

...

Keyword(s):

Energy Demand ◽

Electricity Price ◽

Demand Elasticity ◽

Energy Price ◽

Retail Market ◽

Specific Time ◽

Optimal Price ◽

Numerical Case Study

In the deregulated retail market, consumers should have more right of choice for paying for their energy demand. This paper focuses on the design of electricity price package mechanism in retail market considering the demand elasticity of consumers. An optimal price package mechanism is proposed to incentivize consumers for peak-clipping/valley-filling. Consumers are able to choose the appropriate one from a set of price packages, each of which consists of specific time-of-use energy price and maximum-demand price. A numerical case study has shown the usefulness and effectiveness of the proposed mechanism.

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Sustainable and traditional technologies in Kutahya historic houses and their contribution to circularity: the case of Lajos Kossuth house

VITRUVIO - International Journal of Architectural Technology and Sustainability ◽

10.4995/vitruvio-ijats.2021.15452 ◽

2021 ◽

Vol 6 (1) ◽

pp. 92

Author(s):

Betül Ankaralıgil ◽

Gülşen Dişli

Keyword(s):

Traditional Knowledge ◽

Energy Demand ◽

Knowledge Systems ◽

Service Systems ◽

Historic Buildings ◽

Construction Technology ◽

Building Systems ◽

Heritage Buildings ◽

Cradle To Cradle

<p>It is important to preserve historic buildings in their original conditions, not only to protect building integrity but also to sustain Traditional Knowledge Systems. As stated by ICCROM, those Traditional Knowledge Systems play an important role in the conservation and management of heritage. Among them, building service systems including heating, cooling, ventilation, lighting, drainage, and their architectural construction technology help sustain heritage buildings and extend their life cycle with a minimum level of energy demand. Passive survivability means also contribute to comfort conditions, opening new scenarios for the designing of contemporary buildings. Hence, in this research, first, traditional Kutahya houses were examined in terms of their construction, technology, and architecture. Then, among them, Lajos Kossuth House, dated the 18<sup>th</sup> century, has been chosen as an exemplary to investigate its traditional building service systems in more detail from the point of circularity in construction, their contribution to circular economy, Cradle to Cradle (C2C) strategies, and design for adaptability principles (DfA). It is observed that they are mostly in a well-preserved condition in terms of both function and character-defining features. However, after 1982, during its refurbishment work to be used as a museum, some of its original details, especially the ones related to waste and clean water were destroyed. To be able to sustain and protect the rest of the original service systems and related architectural construction details in this case study building, they should first be documented, well defined and their recognition should be increased to serve as a model for the maintenance of similar building systems. In addition, it might be possible to transfer the knowledge of those passive survivability means and circular construction principles to contemporary buildings.</p>

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