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Digital and intelligent buildings are critical to realizing efficient building energy operations and a smart grid. With the increasing digitalization of processes throughout the life cycle of buildings, data exchanged between stakeholders and between building systems have grown significantly. However, a lack of semantic interoperability between data in different systems is still prevalent and hinders the development of energy-oriented applications that can be reused across buildings, limiting the scalability of innovative solutions. Addressing this challenge, our review paper systematically reviews metadata schemas and ontologies that are at the foundation of semantic interoperability necessary to move toward improved building energy operations. The review finds 40 schemas that span different phases of the building life cycle, most of which cover commercial building operations and, in particular, control and monitoring systems. The paper’s deeper review and analysis of five popular schemas identify several gaps in their ability to fully facilitate the work of a building modeler attempting to support three use cases: energy audits, automated fault detection and diagnosis, and optimal control. Our findings demonstrate that building modelers focused on energy use cases will find it difficult, labor intensive, and costly to create, sustain, and use semantic models with existing ontologies. This underscores the significant work still to be done to enable interoperable, usable, and maintainable building models. We make three recommendations for future work by the building modeling and energy communities: a centralized repository with a search engine for relevant schemas, the development of more use cases, and better harmonization and standardization of schemas in collaboration with industry to facilitate their adoption by stakeholders addressing varied energy-focused use cases.

Increasing amounts of data are available from lighting and other building systems. In commercial buildings, these data can be used to improve system and energy performance, detect and diagnose faults, and facilitate maintenance. Building data are not only of interest to owners and operators of the building systems, however. Owners and operators of similar buildings, manufacturers of building systems, utilities, and city agencies also have interesting use cases. Energy data can, for example, be used to verify the performance of energy-conservation measures, issue renewable-energy certificates, and financially settle grid services. Increased data sharing, however, significantly expands the cyber-attack surface, creating new challenges. In this work, blockchain is explored as an option for ensuring the integrity of data that are shared by lighting and other building systems. Blockchain fundamentals and variants are briefly reviewed, and value propositions relevant to building systems are discussed. A recently developed blockchain applicability framework (BAF) that builds upon and addresses the limitations of previous applicability models is also briefly reviewed. The BAF is used to assess the suitability of blockchain over other technologies or approaches for building-data applications, using emerging connected lighting systems as an example use case.

To date, all three reports in the retail lamps series have focused on basic performance parameters, such as lumen output, efficacy, and color quality. This report goes a step further, examining the photoelectric characteristics (i.e., dimming and flicker) of a subset of lamps from CALiPER Retails Lamps Study 3. Specifically, this report focuses on the dimming, power quality, and flicker characteristics of 14 LED A lamps, as controlled by four different retail-available dimmers. The results demonstrate notable variation across the various lamps, but little variation between the four dimmers. Overall, the LED lamps: ~tended to have higher relative light output compared to the incandescent and halogen benchmark at the same dimmer output signal (RMS voltage). The lamps’ dimming curves (i.e., the relationship between control signal and relative light output) ranged from linear to very similar to the square-law curve typical of an incandescent lamp. ~generally exhibited symmetrical behavior—the same dimming curve—when measured proceeding from maximum to minimum or minimum to maximum control signal. ~mostly dimmed below 10% of full light output, with some exceptions for specific lamp and dimmer combinations ~exhibited a range of flicker characteristics, with many comparing favorably to the level typical of a magnetically-ballasted fluorescent lamp throughmore » at least a majority of the dimming range. ~ always exceeded the relative (normalized) efficacy over the dimming range of the benchmark lamps, which rapidly decline in efficacy when they are dimmed. This report generally does not attempt to rank the performance of one product compared to another, but instead focuses on the collective performance of the group versus conventional incandescent or halogen lamps, the performance of which is likely to be the baseline for a majority of consumers. Undoubtedly, some LED lamps perform better—or more similar to conventional lamps—than others. Some perform desirably for one characteristic, but not others. Consumers (and specifiers) may have a hard time distinguishing better-performing lamps from one another; at this time, physical experimentation is likely the best evaluation tool.« less

Two different types of one-component room temperature vulcanizing (RTV) silicone rubber (Dow Corning 3140 and 730 RTV) are examined as alternatives to PVC for formulating ion-selective membranes. Ion-selective membranes are made by incorporating five different sodium ionophores along with either a plasticizer or an ionic additive (without plasticizer). In most cases, these silicone rubber based membranes exhibit better potentiometric ion response and selectivities when formulated with plasticizer rather than with ionic additive. Incorporating high levels of plasticizer does not appreciably affect the adhesion of 3140 RTV-based membranes, but it significantly deteriorates the adhesion of 730 RTV-based membranes. Membranes based upon 730 RTV have lower impedances than those based upon 3140 RTV, and in fact compare favorably to similarly formulated PVC-based membranes in this regard; as a result, they are better suited for plasticizer-free membrane systems. The use of membranes based upon either of the RTV materials rather than their PVC-based counterparts greatly enhances the lifetime of solid-state sensors.

This report focuses on human-evaluated characteristics, including beam quality, shadow quality, and color quality. Using a questionnaire that included rank ordering, opinions on 27 of the Report 20 PAR38 lamps were gathered during a demonstration event for members of the local Illuminating Engineering Society (IES) chapter. This was not a rigorous scientific experiment, and the data should not be extrapolated beyond the scope of the demonstration. The results suggest that many of the LED products compared favorably to halogen PAR38 benchmarks in all attributes considered. LED lamps using a single-emitter design were generally preferred for their beam quality and shadow quality, and the IES members ranking of color quality did not always match the rank according to the color rendering index (CRI).

This report reviews how phase-cut dimmers work, how LEDs differ from the incandescent lamps that the dimmers were historically designed to control, and how these differences can lead to complications when trying to dim LEDs. Compatibility between a specific LED source and a specific phase-cut dimmer is often unknown and difficult to assess, and ensuring compatibility adds complexity to the design, specification, bidding, and construction observation phases for new buildings and major remodel projects. To maximize project success, this report provides both general guidance and step-by-step procedures for designing phase-controlled LED dimming on both new and existing projects, as well as real-world examples of how to use those procedures.

This CALiPER study examines the problems and benefits likely to be encountered with LED products intended to replace linear fluorescent lamps. LED dedicated troffers, replacement tubes, and non-tube retrofit kits were evaluated against fluorescent benchmark troffers in a simulated office space for photometric distribution, uniformity of light on the task surface, suitability of light output, flicker, dimming performance, color quality, power quality, safety and certification issues, ease of installation, energy efficiency, and life-cycle cost.

The Pacific Northwest National Laboratory, operated by Battelle for the U.S. Department of Energy, worked with Intertek to develop a procedure for stress testing medium screw-base light sources. This procedure, composed of alternating stress cycles and performance evaluation, was used to qualitatively compare and contrast the durability and reliability of the Philips 60W replacement lamp L Prize entry with market-proven compact fluorescent lamps (CFLs) with comparable light output and functionality. The stress cycles applied simultaneous combinations of electrical, thermal, vibration, and humidity stresses of increasing magnitude. Performance evaluations measured relative illuminance, x chromaticity and y chromaticity shifts after each stress cycle. The Philips L Prize entry lamps appear to be appreciably more durable than the incumbent energy-efficient technology, as represented by the evaluated CFLs, and with respect to the applied stresses. Through the course of testing, all 15 CFL samples permanently ceased to function as a result of the applied stresses, while only 1 Philips L Prize entry lamp exhibited a failure, the nature of which was minor, non-destructive, and a consequence of a known (and resolved) subcontractor issue. Given that current CFL technology appears to be moderately mature and no Philips L Prize entry failures could be produced withinmore » the stress envelope causing 100 percent failure of the benchmark CFLs, it seems that, in this particular implementation, light-emitting diode (LED) technology would be much more durable in the field than current CFL technology. However, the Philips L Prize entry lamps used for testing were carefully designed and built for the competition, while the benchmark CFLs were mass produced for retail sale—a distinction that should be taken into consideration. Further reliability testing on final production samples would be necessary to judge the extent to which the results of this analysis apply to production versions of the Philips L Prize entry.« less

The IEEE Standards Working Group, IEEE PAR1789 “Recommending practices for modulating current in High Brightness light emitting diodes (LEDs) for mitigating health risks to viewers” has been formed to advise the lighting industry, ANSI/NEMA, IEC, EnergyStar and other standards groups about the emerging concern of flicker in LED lighting. This paper intends to introduce new measures and definitions of lamp flicker in lighting. The discussion represents on-going work in IEEE PAR1789 that is vital to designing safe LED lamp drivers.

Potentiometric chemical sensors are presented as a case study in the use of screen printing for process partitioning. After CMOS processing, the authors print silver epoxy over the openings in the overglass layer to the aluminum input pads; the silver forms a stable chemical interface to the membranes, and the epoxy forms a strong physical bond to them. The screen-printed silver epoxy allows the use of conventional aluminum metallization in the microelectronic circuits. The polymeric membranes are applied and patterned with screen printing. Membranes of different compositions can be deposited on the various sites of a multisensor chip by simply repositioning the mask and repeating the screen print/cure cycle. There is no cross-contamination of membranes. >

Background LED (Light Emitting Diode) based lighting has been predicted to reach as much as 60% share of the global lighting market in the next 10 years. It is characterized by exceptional lifetime and excellent energy efficiency. However potential health concerns have been associated with flicker in some LED lighting technologies. Aims/Objectives/Purpose The IEEE PAR1789 Working Group has undertaken a risk assessment of potential hazards associated with flicker in LED lighting as part of an effort to develop Recommended Practices of Modulating Current in High Brightness LEDs for Mitigating Health Risks to Viewers. Methods Information on potential health effects of flicker was collected through an extensive literature review and consultation with experts. A risk assessment was conducted following the Eurosafe framework model of risk assessment. Results/Outcome Potential adverse effects of flicker include seizure, stroboscopic effects, migraine, exacerbation of repetitive behaviour in persons with autism, and asthenopic effects including eyestrain, fatigue, and reduced performance on visual tasks. Some health effects are well understood in terms of susceptible subgroups, prevalence and influential parameters while other potential hazards are less extensively studied. Therefore the risk assessment incorporates informational certainty as well as probability and severity of potential effects. Significance/Contribution to the Field Enable confidence in safe use and guidance for safe design of an environmentally important lighting technology.

This chapter elaborates batch fabricated amperometric biosensors. An important barrier to the broad use of biosensors has been an inability to batch fabricates devices having a wide enough range of applicability. A means for batch fabrication that has only been partially realized is the application of semiconductor processing technology. The compatible batch electrode formation and enzyme immobilization technologies for fabricating amperometric biosensors are demonstrated. Electrodes are made using semiconductor thin film processes, and multiple enzymes are selectively immobilized on electrode surfaces using precision screen printing technology. This technique has been proven effective for depositing ionophore-doped membranes in the formation of solid-contact ion selective electrodes. This immobilization technique should be useful for many enzymatic, and immunochemical methods. In addition, all processes described are industry compatible with bulk CMOS technology, allowing for easy integration of active circuitry.