25,456 research outputs found
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Integrating Smart Ceiling Fans and Communicating Thermostats to Provide Energy-Efficient Comfort
The project goal was to identify and test the integration of smart ceiling fans and communicating thermostats. These highly efficient ceiling fans use as much power as an LED light bulb and have onboard temperature and occupancy sensors for automatic operationbased on space conditions. The Center for the Environment (CBE) at UC Berkeley led the research team including TRC, Association for Energy Affordability (AEA), and Big Ass Fans (BAF). The research team conducted laboratory tests, installed99 ceiling fans and 12 thermostats in four affordable multifamily housing sites in California’s Central Valley, interviewed stakeholders to develop a case study, developed an online design tool and design guide, outlined codes and standards outreach, and published several papers.The project team raised indoor cooling temperature setpoints and used ceiling fans as the first stage of cooling; this sequencing of ceiling fans and air conditioningreducesenergy consumption, especially during peak periods, while providing thermal comfort.The field demonstration resulted in 39% measured compressor energy savings during the April–October cooling seasoncompared to baseline conditions, normalized for floor area. Weather-normalized energy use varied from a 36% increase to 71% savings, withmedian savings of 15%.This variability reflects the diversity in buildings, mechanical systems, prior operation settings, space types, andoccupants’ schedules,preferences, and motivations. All commercial spaces with regular occupancy schedules (and twoof the irregularly-occupied commercial spaces and one of the homes) showed energy savings on an absolute basis before normalizing for warmer intervention temperatures,and 10 of 13 sites showed energy savings on a weather-normalized basis. The ceiling fans provided cooling for one site for months during hot weather when the coolingequipment failed.Occupants reported high satisfaction with the ceiling fans and improved thermal comfort. This technology can apply to new and retrofit residential and commercial buildings
Post-Occupancy Evaluation and IEQ Measurements from 64 Office Buildings: Critical Factors and Thresholds for User Satisfaction on Thermal Quality
The indoor environmental quality (IEQ) of buildings can have a strong influence on occupants’ comfort, productivity, and health. Post-occupancy evaluation (POE) is necessary in assessing the IEQ of the built environment, and it typically relies on the subjective surveys of thermal quality, air quality, visual quality, and acoustic quality. In this research, we expanded POE to include both objective IEQ measurements and the technical attributes of building systems (TABS) that may affect indoor environment and user satisfaction. The suite of three tools, including user satisfaction survey, workstation IEQ measurements, and TABS in the National Environmental Assessment Toolkit (NEAT) has been deployed in 1601 workstations in 64 office buildings, generating a rich database for statistical evaluation of possible correlations between the physical attributes of workstations, environmental conditions, and user satisfaction. Multivariate regression and multiple correlation coefficient statistical analysis revealed the relationship between measured and perceived IEQ indices, interdependencies between IEQ indices, and other satisfaction variables of significance. The results showed that overall, 55% of occupants responded as “satisfied” or “neutral”, and 45% reported being “dissatisfied” in their thermal quality. Given the dataset, air temperature in work area, size of thermal zone, window quality, level of temperature control, and radiant temperature asymmetry with façade are the critical factors for thermal quality satisfaction in the field. As a result, the outcome of this research contributes to identifying correlations between occupant satisfaction, measured data, and technical attributes of building systems. The presented integrated IEQ assessment method can further afford robust predictions of building performance against metrics and guidelines for IEQ standards to capture revised IEQ thresholds that impact building occupants’ satisfaction.</jats:p
Policy Design for Controlling Set-Point Temperature of ACs in Shared Spaces of Buildings
Air conditioning systems are responsible for the major percentage of energy
consumption in buildings. Shared spaces constitute considerable office space
area, in which most office employees perform their meetings and daily tasks,
and therefore the ACs in these areas have significant impact on the energy
usage of the entire office building. The cost of this energy consumption,
however, is not paid by the shared space users, and the AC's temperature
set-point is not determined based on the users' preferences. This latter factor
is compounded by the fact that different people may have different choices of
temperature set-points and sensitivities to change of temperature. Therefore,
it is a challenging task to design an office policy to decide on a particular
set-point based on such a diverse preference set. As a result, users are not
aware of the energy consumption in shared spaces, which may potentially
increase the energy wastage and related cost of office buildings. In this
context, this paper proposes an energy policy for an office shared space by
exploiting an established temperature control mechanism. In particular, we
choose meeting rooms in an office building as the test case and design a policy
according to which each user of the room can give a preference on the
temperature set-point and is paid for felt discomfort if the set-point is not
fixed according to the given preference. On the other hand, users who enjoy the
thermal comfort compensate the other users of the room. Thus, the policy
enables the users to be cognizant and responsible for the payment on the energy
consumption of the office space they are sharing, and at the same time ensures
that the users are satisfied either via thermal comfort or through incentives.
The policy is also shown to be beneficial for building management. Through
experiment based case studies, we show the effectiveness of the proposed
policy.Comment: Journal paper accepted in Energy & Buildings (Elsevier
Solar Decathlon Latin America and Caribbean: Comfort and the Balance between Passive and Active Design
This article contains an overall analysis of the results obtained by the four highest scoring
teams in the Solar Decathlon Latin America and Caribbean 2015 collegiate sustainable habitat
competition. Considering that the prototypes developed were based on energy self-su ciency when
operational, it was considered necessary to propose this analysis based on the degree of suitability of
each of these models based on their di erent performances from the perspective of comfort conditions.
It was observed that the design of the prototypes did not manage to properly adjust the relationship
between passive and active conditioning elements based on the location’s conditions. Accordingly,
this article concludes that a balance of the two aforementioned conditioning modes recorded better
results based on the measurements taken
Assessment of Indoor Environmental Quality for Retrofitting Classrooms with An Egg-Crate Shading Device in A Hot Climate
In the Mediterranean climate, a large number of educational buildings suffer from
discomfort due mostly to energy-deficient thermal envelopes and a lack of cooling systems.
Impending climate change is expected to worsen overheating in classrooms, especially during
heatwave periods. Therefore, the protection of window openings to reduce incident solar radiation
while maintaining adequate indoor environmental quality must be considered a necessary key focus.
The main objective of this research is to assess the influence of an egg-crate shading device on the
indoor environmental quality of a classroom in Southern Spain. To do so, two classrooms—with and
without this shading device—were simultaneously monitored over a whole year. The implementation
of an egg-crate shading device allowed for a significant reduction of the incident solar radiation,
both in summer and mid-season (around 45–50%), which objectively slightly conditioned indoor
operative temperatures. Given the noticeable influence of the user patterns observed, indoor
illuminance was also improved, as the rolling shutters tended to be opened at higher aperture levels
Assessment of Indoor Environmental Quality for Retrofitting Classrooms with An Egg-Crate Shading Device in A Hot Climate
In the Mediterranean climate, a large number of educational buildings suffer from
discomfort due mostly to energy-deficient thermal envelopes and a lack of cooling systems.
Impending climate change is expected to worsen overheating in classrooms, especially during
heatwave periods. Therefore, the protection of window openings to reduce incident solar radiation
while maintaining adequate indoor environmental quality must be considered a necessary key focus.
The main objective of this research is to assess the influence of an egg-crate shading device on the
indoor environmental quality of a classroom in Southern Spain. To do so, two classrooms—with and
without this shading device—were simultaneously monitored over a whole year. The implementation
of an egg-crate shading device allowed for a significant reduction of the incident solar radiation,
both in summer and mid-season (around 45–50%), which objectively slightly conditioned indoor
operative temperatures. Given the noticeable influence of the user patterns observed, indoor
illuminance was also improved, as the rolling shutters tended to be opened at higher aperture levels
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A Prototype Toolkit For Evaluating Indoor Environmental Quality In Commercial Buildings
Measurement of building environmental parameters is often complex, expensive, and not easily proceduralized in a manner that covers all commercial buildings. Evaluating building indoor environmental quality performance is therefore not standard practice. This project developed a prototype toolkit that addressed existing barriers to widespread indoor environmental quality performance evaluation. A toolkit with both hardware and software elements was designed for practitioners around the indoor environmental quality requirements of the American Society of Heating, Refrigeration and Air Conditioning Engineers / Chartered Institution of Building Services / United States Green Building Council Performance Measurement Protocols. This unique toolkit was built on a wireless mesh network with a web-based data collection, analysis, and reporting application. The toolkit provided a fast, robust deployment of sensors, real-time data analysis, Performance Measurement Protocol-based analysis methods and a scorecard and report generation tools. A web-enabled Geographic Information System-based metadata collection system also reduced field-study deployment time. The toolkit was evaluated through three case studies, which were discussed in this report
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High-Performance Integrated Window and Façade Solutions for California
The researchers developed a new generation of high-performance façade systems and supporting design and management tools to support industry in meeting California’s greenhouse gas reduction targets, reduce energy consumption, and enable an adaptable response to minimize real-time demands on the electricity grid. The project resulted in five outcomes: (1) The research team developed an R-5, 1-inch thick, triplepane, insulating glass unit with a novel low-conductance aluminum frame. This technology can help significantly reduce residential cooling and heating loads, particularly during the evening. (2) The team developed a prototype of a windowintegrated local ventilation and energy recovery device that provides clean, dry fresh air through the façade with minimal energy requirements. (3) A daylight-redirecting louver system was prototyped to redirect sunlight 15–40 feet from the window. Simulations estimated that lighting energy use could be reduced by 35–54 percent without glare. (4) A control system incorporating physics-based equations and a mathematical solver was prototyped and field tested to demonstrate feasibility. Simulations estimated that total electricity costs could be reduced by 9-28 percent on sunny summer days through adaptive control of operable shading and daylighting components and the thermostat compared to state-of-the-art automatic façade controls in commercial building perimeter zones. (5) Supporting models and tools needed by industry for technology R&D and market transformation activities were validated. Attaining California’s clean energy goals require making a fundamental shift from today’s ad-hoc assemblages of static components to turnkey, intelligent, responsive, integrated building façade systems. These systems offered significant reductions in energy use, peak demand, and operating cost in California
Microservices and Machine Learning Algorithms for Adaptive Green Buildings
In recent years, the use of services for Open Systems development has consolidated and strengthened. Advances in the Service Science and Engineering (SSE) community, promoted by the reinforcement of Web Services and Semantic Web technologies and the presence of new Cloud computing techniques, such as the proliferation of microservices solutions, have allowed software architects to experiment and develop new ways of building open and adaptable computer systems at runtime. Home automation, intelligent buildings, robotics, graphical user interfaces are some of the social atmosphere environments suitable in which to apply certain innovative trends. This paper presents a schema for the adaptation of Dynamic Computer Systems (DCS) using interdisciplinary techniques on model-driven engineering, service engineering and soft computing. The proposal manages an orchestrated microservices schema for adapting component-based software architectural systems at runtime. This schema has been developed as a three-layer adaptive transformation process that is supported on a rule-based decision-making service implemented by means of Machine Learning (ML) algorithms. The experimental development was implemented in the Solar Energy Research Center (CIESOL) applying the proposed microservices schema for adapting home architectural atmosphere systems on Green Buildings
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