Ambient Temperature Sensor Research Articles

Evaluation of the coefficient of performance of an air source heat pump unit and an air to water heat pump

Air source heat pump (ASHP) water heaters are efficient devices for sanitary hot water heating. The coefficient of performance (COP) of the air to water heat pump (AWHP) is constantly lower than that of the corresponding ASHP unit. The study focused on determining the COP of both the ASHP unit and the AWHP. This was achieved by the implementation of both experimental and simulation methods, with the help of a data acquisition system and the REFPROP software. The system comprised of a 1.2 kW split type ASHP unit and a 150 L high pressure geyser. A power meter, flow meters, temperature sensors, pressure sensors, ambient temperature and relative humidity sensor were installed at precise locations on the split type AWHP. Controlled volumes of 150, 50 and 100 L were drawn off from the AWHP during the morning, afternoon and evening for a year. The average COP for the summer and winter, in terms of the input electrical and output thermal energies of the AWHP were 3.02 and 2.30. The COPs of the ASHP unit, in terms of the change in the enthalpies of the refrigerant at the inlet and the outlet of the condenser and the evaporator, were 3.52 and 2.65 respectively. The study showed that the difference between the COP of the ASHP unit and that of the AWHP could be ascribed to the electrical energy consumed by the fan and the water circulation pump during the vapour compression refrigeration cycles. The work provides an energy optimisation opportunity to the manufacturers of this technology, helping to enhance the efficiency and COP of ASHP water heaters.
 Highlights
 
 The COPt of the ASHP unit was higher than the COPe of the AWHP.
 The COPe of the AWHP was the ratio of the input electrical energy consumed and the output thermal energy gained by the stored water.
 The COPt of the ASHP unit was enthalpies-dependent and a function of inlet and outlet enthalpies of the evaporator and condenser.
 The inlet and outlet refrigerant temperatures profiles of the condenser confirmed thermal energy dissipation.

Android based Wireless Sensor Network (WSN) mobile application on humidity and temperature environmental monitor using CC2650 sensor tag

This research proposed environmental sensing humidity and ambient temperature or object use CC2560 Texas instrument sensor tag device. This device will be implemented on a mobile app to detect surrounding humidity and temperature environment, hoping that it will be used to monitor the user’s daily activity. The sensor will transmit raw data to a central data collector mobile app using Bluetooth Low Energy (BLE) communication and configured with the other same device CC2650 sensor tag in a field with Wireless Sensor Network (WSN). Temperature and Humidity sensing was doing with distance to testing the accurate and sensitivity about the sensor device and the sensor is going work well when the time sampling in second time, the humidity and temperature can follow and change with real time sampling until 30s start from 30.12 and humidity start from 85.81 percent because of specification of the sensor device data transfer very fast wit Bluetooth Low Energy / multi-protocol 2.4 GHz and wireless MCUs with 352-kB flash and 80-kB SRAM, so the device get very little energy, low cost, and have good durability can access data and transmit for a long time.

Wildland firefighters’ thermal exposure in relation to suppression tasks

The main purpose of this study was to characterise the thermal environment and risk of heat burns of wildland firefighters in relation to the suppression tasks performed in real wildland fires. Measurements of air temperature and heat flux were performed by affixing heat flux and ambient temperature sensors on the outer and inner surface of the wildland firefighters’ protective garments. Suppression time was divided according to the task performed in direct attack, backfire, mop-up and patrol. These tasks accounted for 95.2 ± 78.4, 103.3 ± 41.7, 80.5 ± 24.8 and 71.3 ± 53.0 min, respectively. Overall, the mean heat flux was higher during backfire (2165 ± 1604 W m−2) than in direct attack (558 ± 344 W m−2), mop-up (371 ± 254 W m−2) and patrol (354 ± 307 W m−2). However, during the direct attack, average and maximum thermal dose was ~94 and ~110 (kW m−2)4/3 s, respectively. These values are within the threshold of pain and first-degree burns. However, no first-degree burns were reported for the sample. Overall, the thermal exposure measured may be considered light. However, high thermal exposure values may be obtained at specific moments, which may cause first-degree burns in wildland firefighters.

RETRACTED ARTICLE: Experimental and comparative analysis of various solar PV module technologies using module level inverter topologies at south-India for the context-aware application

The PV module structure has observed many improvements in the structure design ever since the days of its origin, so that the performance and durability of PV Module is improved over the period of years. A PV module has a multi-layered structure—an anodized aluminum frame ensures rigidity to the module by coupling together all the components tightly. As solar energy is growing, the demand for electricity is reduced and it is the most prominent technology in the upcoming generations. The solar energy is used to convert the irradiation (i.e. light) into electricity. At present, the most promising energy source in India is the solar energy and the government is also taking major policies to implement the solar PV system. For electrical performance evaluation, an online monitoring tool was used, along with module temperature detector (resistance temperature detector) and solar irradiance detector (silicon reference cell). The temperature and irradiance data make it easier for the conversion of the measured I–V curve to standard test conditions (STC), so that these can then be compared with the name plate data of the module and the average degradation rates (difference of name plate data and measured data divided by the number of years the module was installed in field). Also, at some sites, the site was also equipped with tools like Multi-meter, ambient temperature and humidity sensor tilt angle meter (to measure the inclination angle of the module with respect to horizontal) and compass (to know the direction in which the modules are facing). In this study, we have reviewed a 2.2 kW solar PV system for the context-aware application with eight different PV modules for three different seasons namely summer, rainy and autumn seasons prevailing in south India from January to December. The system was monitored regularly for 24 h using monitoring portal. Sensors are being used to monitor the Coimbatore site’s irradiance, temperature and wind conditions and calculate performance ratio (PR). Results from the study shows that the power generation from 2.2 kW solar PV systems has higher performance in summer when compared to any other seasons in Coimbatore. From the above reliability study the best performed panel technology is Interdigited Back Contact under different conditions with different data analysis.

SMART BLIND STICK PRO

Planet consists of several people one of whom is visually disabled people. Currently, the World Health Organization estimates that 76 million visually disabled individuals are still alive in the world. As a normal human being able to leave his or her life alone, however visually disabled people are dependent on him or her to fulfil the basic needs. This society becomes increasingly evolving, a range of new technologies have been developed that enable blind people to sustain their lives without being dependent but it still has its pitfalls. So we are suggesting a workaround in this to introduce a highly innovative and inexpensive smart blind stick to the visually disabled.In this paper we use ultrasonic sensors for detecting obstacles, global positioning systems (GPS) and global system for mobile communication (GSM) modules for tracking positions and sends a message to the configured number. The thermistor that helps sense the ambient heat temperature and IR sensor to identify the potholes when driving, The individual buzzer is accomplished to get acquainted with the unit. When a person heads towards an obstacle, the buzzer resounds. The main point of view of this program is to guide the visually impaired to their service.

Geospatial assessment of land surface temperature in Nagpur, India: an impact of urbanization

Temperature is one of the factors which affects the meteorological phenomenon prevailing in an urban area and ultimately leads to climate change and global warming. Measurement of surface temperature with conventional temperature sensors is tedious, has single point value and expensive. Satellite data of 2005, 2008, 2010 and 2016 are used to assess the land use land cover (LULC) and to measure the land surface temperature (LST) during the hottest month of May in Nagpur city, India. Based on the image analysis, it is observed that there is an increase in the average temperature from 40.0 to 44.6 oC. This may be due to an increase in built-up area from 55.5 to 69.8% during 2005 to 2016, respectively. It has also been revealed that the outskirts of the city are hotter than the central portion of the city as there is more barren land on the outskirts. Results were compared to ambient temperature sensor that showed good agreement between temperature retrieved from satellite and temperature sensor. The study suggests that urban areas should be developed intermixed with vegetation and plantation and provisions of green belt along the city roads, highways and ring roads. Based on LST and LULC analysis, a green belt of 30 m along both sides of the road would lower the road temperature by 9.3 oC from existing temperature of 44.7 oC. This would help in lowering down the average temperature of the city.

Wearable sensors for personal temperature exposure assessments: A comparative study

The impacts of heat on human health has sparked research on different approaches to measure, map, and predict heat exposure at more accurate and precise spatiotemporal scales. Personal heat sensor studies rely on small sensors that can continuously measure ambient temperatures as individuals move through time and space. The comparison between different types of sensors and sensor placements have yet to be fully researched. The objective of this study is to assess the validity of personal ambient temperature sensors. To accomplish this objective, we evaluated the performance of multiple low-cost wearable sensors (HOBOs, iButton Thermochrons, iButton Hygrochrons, and Kestrel DROP D3FW Fire) for measuring ambient temperature in a (1) field exposure study by varying the placement on human subjects and in a (2) field calibration study by co-locating sensors with fixed site weather station monitors. A secondary aim involved investigating consensus between validation metrics that can be used in future sensor comparison studies. Bland-Altman analysis, correlation coefficients, and index of agreement statistics were used to quantify the difference between sensor and weather station ambient temperature measurements. Results demonstrated significant differences in measured temperatures for sensors based on sensor type and placement on participants. Future research should account for the differences in personal ambient temperature readings based on sensor type and placement.

Estimation Road Surface Temperature Variation Using Commercial Vehicle Ambient Sensor

Road surface temperature is more important than ambient temperature in term of road safety during winter season. The conventional method to collect road surface temperature is to install Road Weather Station(RWS). However RWS can only collect spot information and could be costly. To enhance these problem, this study used the commercial vehicle ambient temperature(VAT) sensors can collect the pattern of air temperature along the road effectively and rapidly. Also the thermal mapping equipment was used to collect the road surface temperature(RST). After that, our research analysed the similarity of the patterns of road surface and ambient temperatures using correlation analysis. The result showed that the patterns of temperature variation collected from VAT sensors are statistically comparable to patterns of road surface temperature variation collected from a thermal mapping. In addition, this research developed a way to segment roadway based on variation in road surface temperature. This segmentation is useful to road authorities for managing the road and providing information based on road segmentation. Although VAT sensors do not provide highly accurate temperature readings, they can identify patterns of surface road temperature on roadway sections. This study found out that the VAT can be estimated the patterns of RST and could be replace the road weather station or thermal mapping system. This information can be used so that individual drivers, commercial vehicle and fleet operators and road authorities acquire critical real-time information on road conditions. Further, using these sensors instead of fixed sensors or thermal mapping can significantly reduce road maintenance costs. Also the result could be applied to the automated driving system to provide the road surface condition in the future.

A comparative study of predicting individual thermal sensation and satisfaction using wrist-worn temperature sensor, thermal camera and ambient temperature sensor

Recent advancements in Internet of Things and Machine Learning have opened the possibility of deploying sensors at a large scale to monitor the environment and to model and predict thermal comfort at an individual level. There has been a growing interest to use physiological information obtained from wearable devices or thermal imaging to improve individual thermal comfort prediction. In this study, we compared the accuracies of using environmental sensing with an air temperature sensor, physiological sensing with a wrist-worn device to monitor wrist skin temperature or thermal camera to monitor facial skin temperatures for predicting individual thermal sensation and satisfaction. The experiment was conducted in a controlled environment without any radiant heat sources or local comfort devices; solely the air temperature was changed. For the conditions studied, our results indicate that using data from an environmental sensor for predicting thermal comfort results in a higher accuracy compared to using physiological sensors (either wearable device or thermal camera) alone. Combining data from both environmental and physiological sensors leads to about 3%–4% higher accuracy than using environmental sensors only. Slight improvement in accuracy from the physiological sensors might not be sufficient to justify the privacy concerns and additional costs of using physiological sensors at a large scale for predicting thermal comfort in environments without radiant heat sources or local comfort devices. Future studies under different environmental conditions with a larger population are needed to better understand the tradeoffs between different sensing methods for predicting thermal comfort at an individual level.

Solar Based Smart Irrigation System Using PID Controller

An approach to minimize the human interface for the agriculture sector is presented in this paper which provides comfort to the farmer in monitoring and performs automatic irrigation operation. Here, a combination of software integrated microcontroller that is Arduino, four real-time sensors fetching input data from field and a DC motor pump as output are used. A controlling technique Proportional Integral and Derivative (PID) controller is integrated into Arduino. The inputs include four sensors: wind speed, ambient temperature, humidity, and radiation sensors while taking soil moisture as the reference point. These four sensors work at different ratios on the basis of PID and penman model of evapotranspiration. The system is powered by a lead-acid battery which is recharged by a solar panel. The four designated sensors measure field conditions and simultaneously send information through wireless communication to a remote placed monitoring device which has a Liquid Crystal Display (LCD). The complete hardware and software modeling is performed in this paper.

In situ measurement of façades with a low U-value: Avoiding deviations

In situ measurements of low thermal transmittance façades are required to ensure compliance with energy performance strategies for new nearly zero-energy buildings (nZEB) and with energy policies for the transition of existing building stock to nZEB. The aim of this paper was to enhance the accuracy of the in situ measurement of low U-value façades, employing the widely used ISO 9869-1:2014 HFM method and exploring the limits of its conditions. To refine the testing conditions, three variables were analysed and compared with indications of ISO 9869-1:2014 and the existing literature: the temperature difference, the test duration and the accuracy of equipment. A continuous experimental campaign was conducted in a building mock-up. The findings showed that to accurately measure in situ low U-value façades, the temperature differences must be greater than those indicated in the existing literature. Temperature differences above 19 °C required a test duration of 72 h, while for lower temperature differences the test duration must be prolonged. The accuracy of temperature sensors had a greater impact on the accuracy of measurement in the initial cycles of the test. Likewise, the accuracy of ambient temperature sensors was found to have a considerable influence on the uncertainty of measurements.

An Area-Efficient Microprocessor-Based SoC With an Instruction-Cache Transformable to an Ambient Temperature Sensor and a Physically Unclonable Function

This paper presents a novel microprocessor-based system-on-chip (SoC) with the capability to transform SRAM in the instruction cache to an ambient temperature sensor and a physically unclonable function (PUF). For the transformation, we extend the original microprocessor without interlocked pipeline stages instruction set architecture and update SRAM peripheral circuits and pipeline control. All the changes are made minimally to reduce hardware overhead and the impact on the original microarchitecture. Compared to the conventional approach implementing dedicated hardware for low duty-cycle sensing and PUF, the proposed transformation approach saves ~9.8 $\times $ silicon area while achieving the performance and robustness comparable to the state of the art in implementing those functions. The efficiency of the approach is verified with an SoC prototyped in a 65-nm CMOS.

In-situ Monitoring of Electrolytic Corrosion on the Caps of HVDC Insulators

The evaluation of the electrolytic corrosion on the hardware of insulators is necessary for long-term operation and maintenance of high-voltage direct current (HVDC) overhead lines. In this paper, the design and development of an online monitoring system are introduced for the measurement of corrosion current and the charge in porcelain and glass disc suspension insulators. A wide range current sensor of a $\mu \text{A}$ -mA level was developed to sample the surface corrosion current. The data acquisition module connected to microampere current sensors, ambient temperature, and relative humidity sensors transmitted filed information to a remote Internet server via general packet radio service. Laboratory tests were carried out to verify the system performance, including the accuracy of current measurement, the stability of power supply, the reliability of communication, and electromagnetic compatibility. It was found that there was good agreement between the monitoring results and the dissection results. Six devices were installed on transmission towers of three ±800-kV HVDC projects in different regions, and all of them have been operating for more than two years from 2015 to 2017. Data stored in the server were exported for further analysis in this paper. Summary statistics on different time scales showed the relationship between corrosion and regions. Based on the records of the most seriously corroded caps, relative humidity and rainfall were found to be two major factors affecting the corrosion rate.

Modelling of an on-farm direct expansion bulk milk cooler to establish baseline energy consumption without milk pre-cooling: A case of Fort Hare Dairy Trust, South Africa

Storage of milk at a low temperature of 4°C inhibits bacterial growth. As such bulk milk coolers (BMC) are used for cooling and storage of milk on dairy farms. This paper presents performance monitoring of a direct expansion bulk milk cooler to establish its baseline energy consumption without milk pre-cooling through mathematical modelling. A data acquisition system comprising a power meter, a data logger, temperature sensors and relative humidity and ambient temperature sensors was constructed to capture the energy consumption of the BMC, room temperature and ambient conditions. On-farm milk records were used to determine milk production per milking session. Two milking times were considered, that is for the morning and the late afternoon periods. The average daily electrical energy consumption of the BMC for the two milking times was 48.31 kWh and 43.23 kWh, respectively. Mathematical models represented as multiple linear regression models were built and developed using the experimental data. The developed mathematical models gave good agreement with the experimental results as evidenced by correlation coefficients of 0.922 and 0.8995. ReliefF algorithm revealed that volume of milk is the principal contributor to the energy consumption of the BMC for both the AM and PM milking.

Individual-based analysis of hair corticosterone reveals factors influencing chronic stress in the American pika.

Glucocorticoids are often measured in wildlife to assess physiological responses to environmental or ecological stress. Hair, blood, saliva, or fecal samples are generally used depending on the timescale of the stress response being investigated and species‐specific considerations. Here, we report the first use of hair samples to measure long‐term corticosterone levels in the climate‐sensitive American pika (Ochotona princeps). We validated an immunoassay‐based measurement of corticosterone extracted from hair samples and compared corticosterone estimates obtained from plasma, hair, and fecal samples of nine pikas. To demonstrate an ecological application of this technique, we characterized physiological stress in 49 pikas sampled and released at eight sites along two elevational transects. Microclimate variation was measured at each site using both ambient and subsurface temperature sensors. We used an information theoretic approach to compare support for linear, mixed‐effects models relating corticosterone estimates to microclimate, body size, and sex. Corticosterone was measured accurately in pika hair samples after correcting for the influence of sample mass on corticosterone extraction efficiency. Hair‐ and plasma‐based estimates of corticosterone were weakly correlated. The best‐supported model suggested that corticosterone was lower in larger, male pikas, and at locations with higher ambient temperatures in summer. Our results are consistent with a general negative relationship between body mass and glucocorticoid concentration observed across mammalian species, attributed to the higher mass‐specific metabolic rates of smaller bodied animals. The higher corticosterone levels in female pikas likely reflected the physiological demands of reproduction, as observed in a wide array of mammalian species. Additionally, we establish the first direct physiological evidence for thermal stress in the American pika through nonlethal sampling of corticosterone. Interestingly, our data suggest evidence for cold stress likely induced during the summer molting period. This technique should provide a useful tool to researchers wishing to assess chronic stress in climate‐sensitive mammals.

Building Central Plant System Performance Optimization through A Virtual Ambient Wet-bulb Temperature Sensor

Ambient wet-bulb temperature measurement is critical in the water-cooled chiller plant system to enhance the holistic energy efficiency through advanced control strategies, such as the cooling tower temperature relief, condenser water supply temperature reset, and so on. The outside air (OA) wet-bulb temperature is usually measured either by a psychrometer or a combination of an OA relative humidity sensor and an OA dry-bulb sensor. However, these conventional measuring devices are notoriously costly and frequently problematic in consideration of the accuracy and reliability. This paper proposes a black-box-based virtual ambient wet-bulb sensor through adopting a low-cost but relatively accurate dry-bulb temperature sensor and the local weather data, either the typical meteorological year (TMY) weather data or the real-time weather data available online. Further, a dynamic real-time calibration algorithm was simultaneously developed to minimize the measurement error. A case study in a ten-story office building in Austin, Texas was implemented to demonstrate the feasibility of this strategy. It reveals that the virtual sensor combined with the uniquely developed control algorithm could greatly improve the readings of the ambient wet-bulb temperature, thus guarantee the in-field chiller plant performance optimization as expected by the proposed control strategies.

Long-term greenhouse gas measurements from aircraft

Abstract. In March 2009 the NOAA/ESRL/GMD Carbon Cycle and Greenhouse Gases Group collaborated with the US Coast Guard (USCG) to establish the Alaska Coast Guard (ACG) sampling site, a unique addition to NOAA's atmospheric monitoring network. This collaboration takes advantage of USCG bi-weekly Arctic Domain Awareness (ADA) flights, conducted with Hercules C-130 aircraft from March to November each year. Flights typically last 8 h and cover a large area, traveling from Kodiak up to Barrow, Alaska, with altitude profiles near the coast and in the interior. NOAA instrumentation on each flight includes a flask sampling system, a continuous cavity ring-down spectroscopy (CRDS) carbon dioxide (CO2)/methane (CH4)/carbon monoxide (CO)/water vapor (H2O) analyzer, a continuous ozone analyzer, and an ambient temperature and humidity sensor. Air samples collected in flight are analyzed at NOAA/ESRL for the major greenhouse gases and a variety of halocarbons and hydrocarbons that influence climate, stratospheric ozone, and air quality. We describe the overall system for making accurate greenhouse gas measurements using a CRDS analyzer on an aircraft with minimal operator interaction and present an assessment of analyzer performance over a three-year period. Overall analytical uncertainty of CRDS measurements in 2011 is estimated to be 0.15 ppm, 1.4 ppb, and 5 ppb for CO2, CH4, and CO, respectively, considering short-term precision, calibration uncertainties, and water vapor correction uncertainty. The stability of the CRDS analyzer over a seven-month deployment period is better than 0.15 ppm, 2 ppb, and 4 ppb for CO2, CH4, and CO, respectively, based on differences of on-board reference tank measurements from a laboratory calibration performed prior to deployment. This stability is not affected by variation in pressure or temperature during flight. We conclude that the uncertainty reported for our measurements would not be significantly affected if the measurements were made without in-flight calibrations, provided ground calibrations and testing were performed regularly. Comparisons between in situ CRDS measurements and flask measurements are consistent with expected measurement uncertainties for CH4 and CO, but differences are larger than expected for CO2. Biases and standard deviations of comparisons with flask samples suggest that atmospheric variability, flask-to-flask variability, and possible flask sampling biases may be driving the observed flask versus in situ CO2 differences rather than the CRDS measurements.

Large-area compatible fabrication and encapsulation of inkjet-printed humidity sensors on flexible foils with integrated thermal compensation

This work presents the simultaneous fabrication of ambient relative humidity (RH) and temperature sensors arrays, inkjet-printed on flexible substrates and subsequently encapsulated at foil level. These sensors are based on planar interdigitated capacitors with an inkjet-printed sensing layer and meander-shaped resistors. Their combination allows the compensation of the RH signals variations at different temperatures. The whole fabrication of the system is carried out at foil level and involves the utilization of additive methods such as inkjet-printing and electrodeposition. Electrodeposition of the printed lines resulted in an improvement of the thermoresistors. The sensors have been characterized and their performances analyzed. The encapsulation layer does not modify the performances of the sensors in terms of sensitivity or response time. This work demonstrates the potential of inkjet-printing in the large-area fabrication of light-weight and cost-efficient gas sensors on flexible substrates.

Temperature changes above the upper hive body reveal the annual development periods of honey bee colonies

Determination of the annual development periods of honey bee colonies can help in synchronising the beekeeper’s activities with the developmental stage of individual bee colonies in apiaries. It is proposed to determine the development periods by measuring and analysing the ambient temperature and the temperature above the upper hive body. The temperature above the upper hive body is proportional to the energy which is released during bee colony activities. Throughout the year in 2000, measurements with interval of 15min of the temperature in 14 honey bee colonies was done in Latvia, in the Riga region. One sensor per colony was located above the upper hive body. The annual curve of the average day and night temperature was approximated by five linear pieces that possibly correspond to particular periods. Explicit transition points to the next period were determined. Five sequential periods have been proposed in the bee colony’s development: (1) winter brood rearing, (2) spring brood rearing, (3) summer brood rearing, (4) autumn brood rearing and (5) autumn broodless period. These periods collectively form a hat-like annual profile. All brood rearing periods demonstrate high thermal discipline: the hive temperature follows linear dynamics in spite of fluctuations in the ambient temperature.A simple measurement system and criteria for automatic determination of transition from one period to another for apiary has been developed and tested. Thermal measurements above the upper hive body efficiently determine the transition from one period to another in the apiary. The computational system for the determination of developmental periods should be equipped with at least one ambient temperature sensor per apiary and one temperature sensor per observed bee colony.

Advances in materials for room temperature hydrogen sensors

Hydrogen (H(2)), as a source of energy, continues to be a compelling choice in applications ranging from fuel cells and propulsion systems to feedstock for chemical, metallurgical and other industrial processes. H(2), being a clean, reliable, and affordable source, is finding ever increasing use in distributed electric power generation and H(2) fuelled cars. Although still under 0.1%, the distributed use of H(2) is the fastest growing area. In distributed H(2) storage, distribution, and consumption, safety continues to be a critical aspect. Affordable safety systems for distributed H(2) applications are critical for the H(2) economy to take hold. Advances in H(2) sensors are driven by specificity, reliability, repeatability, stability, cost, size, response time, recovery time, operating temperature, humidity range, and power consumption. Ambient temperature sensors for H(2) detection are increasingly being explored as they offer specificity, stability and robustness of high temperature sensors with lower operational costs and significantly longer operational lifetimes. This review summarizes and highlights recent developments in room temperature H(2) sensors.