scholarly journals Polymer Nanocomposites for Lowering Heating and Cooling Loads in Buildings

Proceedings ◽  
2020 ◽  
Vol 69 (1) ◽  
pp. 35
Author(s):  
George T. Stiubianu
Keyword(s):  
Thermal Management ◽  
Polymer Nanocomposites ◽  
Low Cost ◽  
Management Strategies ◽  
Thermal Control ◽  
Point Temperature ◽  
Set Point ◽  
Heating And Cooling ◽  
Environment Control ◽  
The Individual

Worldwide, buildings consume over 40% of the total commercial energy, and 36% of this amount is dedicated to the heating and cooling of buildings. Therefore, building environment control systems require efficient thermal management. An ideal thermal management that could lower the energy load for cooling and heating respectively would combine passive strategies for thermal control, which are characterized by low cost, straightforward implementation, and energy efficiency, with the on-demand control of heating and cooling, specific for active thermal management strategies. The scientific challenge of building an efficient platform for thermal control was addressed by using block copolymer materials in the development of nanocomposites with dynamically tunable thermal infrared properties. The polymer nanocomposites manage 60–70% of the metabolic heat flux from sedentary individuals and can modulate changes in the individual body temperature within a set-point temperature range of 8 °C. This increase in the set-point temperature translates into use of air conditioning for cooling/heating with a significantly lowered load, which would further translate into a 4.3% decrease of global energy consumption.

Enhancing the Performance of Photovoltaic Powered Reverse Osmosis Desalination Systems by Active Thermal Management

2011 ◽  
Author(s):  
Leah Kelley ◽  
Amy M. Bilton ◽  
Steven Dubowsky
Keyword(s):  
Thermal Management ◽  
Reverse Osmosis ◽  
Fresh Water ◽  
Low Cost ◽  
Simulation Models ◽  
Cost Effective ◽  
Thermal Control ◽  
Solar Panel ◽  
Experimental Results ◽  
Feed Water

Reverse osmosis (RO) is a well-known process for desalinating seawater and brackish groundwater. Desalination is energy-intensive, so using photovoltaic (PV) panels to power the process is an attractive and cost-effective concept, especially for community-scale systems. Increasing the system efficiency will lower the total cost of water produced, making the systems more economically competitive for a greater number of geographic locations. It is noted in this paper that the amount of water produced by a PV-powered RO (PVRO) system can be increased if the temperatures of the solar panel and the reverse osmosis feed water are actively managed. For a given level of solar radiation, a photovoltaic panel produces more power at a lower temperature. Also, for a given power, an RO system produces more clean water at a higher input (feed) water temperature. An active thermal management system is needed to exploit these complementary characteristics by cooling the solar panel and warming the RO feed water, increasing the amount of fresh water produced. This can be accomplished by running the RO feed water through a heat exchanger attached to the back of the solar panel, cooling it. Furthermore, the ability to cool the solar panels permits the addition of low-cost, flat-plate concentrating mirrors to be used with the PV panels, which further increases the PV power output. The flow of the water through the respective units must be actively controlled as there are limits for the maximum temperatures of both the RO water and PV panels. In this paper, a concept for an active PVRO thermal control system is presented. Simulations and experimental results show the effectiveness of this approach. In experiment, a 57% increase in fresh water production was achieved. These experimental results agree well with simulation models.

scholarly journals Development of Simple Devices for Control of Temperature above and below Ambient on Simple Pipetting Stations

1998 ◽  
Vol 3 (2) ◽  
pp. 38-42
Author(s):  
Theodore E. Mifflin ◽  
Robin A. Felder
Keyword(s):  
Molecular Biology ◽  
Temperature Variation ◽  
Rna Aptamers ◽  
Molecular Diagnostic ◽  
Point Temperature ◽  
Set Point ◽  
Heating And Cooling

Robotic pipetting stations are becoming increasingly popular to perform a variety of different laboratory analyses, including use of biochemical, chemical, and molecular biology reactions. As molecular diagnostic (MDx) analyses are adapted to pipetting stations, their need for additional resources on the pipetting stations such as heating and cooling will also grow. We designed and constructed small (< 150 cm2) accessories for use on a popular pipetting station. Both have small footprints and were built using readily available components. The microplate heater could achieve set point temperature within 10 minutes of activation and exhibited minimal temperature variation. The cooler was designed to be a passively cooled resource that could contain up to 15 Eppendorf tubes and maintain the temperature at least 20 degrees below ambient for at least two hours. Both units have been used to automate a coupled series of molecular biology reactions that yield RNA aptamers. We believe these two devices can be widely utilized with minor modifications of any pipetting station that requires heating or cooling capabilities on the pipetting station's deck.

scholarly journals THE IMPACT OF OCCUPANT BEHAVIOUR ON RESIDENTIAL GREENHOUSE GAS EMISSIONS REDUCTION

2015 ◽  
Vol 10 (4) ◽  
pp. 127-140 ◽  
Author(s):  
Joshua Hetherington ◽  
Astrid Roetzel ◽  
Robert Fuller
Keyword(s):  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Energy Use ◽  
Occupant Behaviour ◽  
Gas Emissions ◽  
Point Temperature ◽  
Set Point ◽  
Heating And Cooling ◽  
Reduce Emissions ◽  
The Impact

In 2011–12, greenhouse gas emissions from the Australian residential sector were 101.6 Mt and are expected to grow by 38% by 2050. In order to reduce these emissions, much emphasis has been placed on increasing the energy efficiency of buildings and appliances. Occupant behaviour, however, is probably the single most significant factor which determines energy use and emissions. This paper describes research undertaken to rank the most common occupant behaviours, based upon their impact on greenhouse gas emissions associated with residential energy use, in an architect-designed house in Australia. The occupant behaviours investigated were changing: the heating and cooling temperature set points, window openings, external blind use and lighting use. Simulations were carried out using Primero and EnergyPlus software. Based on the simulation results of greenhouse gas emissions, the following ranking of overall influence (from most influential to the least) has been determined: external blind use was one of the most effective measures to reduce emissions. Cooling set point temperature was similarly important with the magnitude of impact depending on the set point e.g. a 2°C increase had an impact comparable to the use of external blinds. The impact of the heating set point temperature was also dependent on the set point and overall slightly lower compared to the cooling set point temperature. Lighting use was the least influential parameter in the context of this study.

Retrospective on the 1970’s “Low Cost Shore Protection” program

Shore & Beach ◽  
2019 ◽  
pp. 3-12
Author(s):  
Joan Pope
Keyword(s):  
Coastal Erosion ◽  
Low Cost ◽  
Management Strategies ◽  
Public Information ◽  
Coastal Engineering ◽  
Shoreline Erosion ◽  
Shore Protection ◽  
Demonstration Program ◽  
Alternative Approaches ◽  
The U.S

In the 1970s, the U.S. Congress authorized and funded a five-year demonstration program on low-cost methods for shore protection called the “U.S. Army Engineers Shoreline Erosion Control Demonstration (Section 54) Program.” The Section 54 also known as the “Low-Cost Shore Protection” demonstration program is revisited. Demonstration and monitoring sites including the materials, devices, vegetative plantings, approaches tested, and program findings are discussed. Simply put, a major finding of the Section 54 program was that the concept of “low-cost shore protection” was a bit naïve. However, the program did lead to a wealth of public information documents and practical coastal engineering lessons that are still resonating as home owners, communities, and engineers consider alternative approaches for managing coastal erosion. The program structure and findings are applicable 40 years later as consideration is given toward the use of Natural and Nature-based Features (NNBF) for addressing coastal erosion. Evolution in thought relative to coastal erosion and shoreline enhancement activities since the 1970s has built upon many of the lessons and concepts of the Section 54 program and other real-world coastal erosion management success-failure experiences. This growth has led to a modern appreciation that those features that emulate NNBF are promising and responsible alternative coastal erosion management strategies if proper engineering standard elements of design are included in the project.

Control of an adiabatic continuous reactor by feeding catalyst

1980 ◽  
Vol 45 (11) ◽  
pp. 2903-2918 ◽  
Author(s):  
Josef Horák ◽  
Zina Valášková ◽  
František Jiráček
Keyword(s):  
Steady State ◽  
Reaction Temperature ◽  
Continuous Reactor ◽  
Control Element ◽  
Inlet Temperature ◽  
Switching Cycle ◽  
Point Temperature ◽  
Set Point ◽  
Constant Rate ◽  
Laboratory Reactor

Algorithms have been presented, analyzed and experimentally tested to stabilize the reaction temperature at constant inlet temperature and composition of the feed by controlled dispensing of the catalyst. The information for the control element is the course of the reaction temperature. If the temperature of the reaction mixture is below the set point, the catalyst is being fed into the reactor at a constant rate. If the reaction temperature is higher the catalyst dispenser is blocked; dispensing of the catalyst is not resumed until the set point temperature has been reached again. The amount of catalyst added is a function of the duration of the switching cycle. The effect has been discussed of the form of this function on the course of the switching cycle. The results have been tested experimentally on a laboratory reactor controlled in an unstable steady state.

scholarly journals Thermal management strategies for gallium oxide vertical trench-fin MOSFETs

2021 ◽  
Vol 129 (8) ◽  
pp. 085301
Author(s):  
Robert H. Montgomery ◽  
Yuewei Zhang ◽  
Chao Yuan ◽  
Samuel Kim ◽  
Jingjing Shi ◽  
...  
Keyword(s):  
Thermal Management ◽  
Gallium Oxide ◽  
Management Strategies

scholarly journals Automated Residential Energy Audits Using a Smart WiFi Thermostat-Enabled Data Mining Approach

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2500
Author(s):  
Abdulrahman Alanezi ◽  
Kevin P. Hallinan ◽  
Kefan Huang
Keyword(s):  
Low Cost ◽  
Model Development ◽  
Cost Savings ◽  
Measured Temperature ◽  
Single Family ◽  
Furnace Efficiency ◽  
Heating And Cooling ◽  
Data Mining Approach ◽  
Energy Auditing ◽  
Energy Audits

Smart WiFi thermostats, when they first reached the market, were touted as a means for achieving substantial heating and cooling energy cost savings. These savings did not materialize until additional features, such as geofencing, were added. Today, average savings from these thermostats of 10–12% in heating and 15% in cooling for a single-family residence have been reported. This research aims to demonstrate additional potential benefit of these thermostats, namely as a potential instrument for conducting virtual energy audits on residences. In this study, archived smart WiFi thermostat measured temperature data in the form of a power spectrum, corresponding historical weather and energy consumption data, building geometry characteristics, and occupancy data were integrated in order to train a machine learning model to predict attic and wall R-Values, furnace efficiency, and air conditioning seasonal energy efficiency ratio (SEER), all of which were known for all residences in this study. The developed model was validated on residences not used for model development. Validation R-squared values of 0.9408, 0.9421, 0.9536, and 0.9053 for predicting attic and wall R-values, furnace efficiency, and AC SEER, respectively, were realized. This research demonstrates promise for low-cost data-based energy auditing of residences reliant upon smart WiFi thermostats.

scholarly journals WattScale

2021 ◽  
Vol 2 (1) ◽  
pp. 1-25
Author(s):  
Srinivasan Iyengar ◽  
Stephen Lee ◽  
David Irwin ◽  
Prashant Shenoy ◽  
Benjamin Weil
Keyword(s):  
Cooling System ◽  
Large Population ◽  
Ground Truth ◽  
Detection Algorithm ◽  
Building Envelope ◽  
Ground Truth Data ◽  
Heating And Cooling ◽  
Data Driven Approach ◽  
Execution Mode ◽  
The Individual

Buildings consume over 40% of the total energy in modern societies, and improving their energy efficiency can significantly reduce our energy footprint. In this article, we present WattScale, a data-driven approach to identify the least energy-efficient buildings from a large population of buildings in a city or a region. Unlike previous methods such as least-squares that use point estimates, WattScale uses Bayesian inference to capture the stochasticity in the daily energy usage by estimating the distribution of parameters that affect a building. Further, it compares them with similar homes in a given population. WattScale also incorporates a fault detection algorithm to identify the underlying causes of energy inefficiency. We validate our approach using ground truth data from different geographical locations, which showcases its applicability in various settings. WattScale has two execution modes—(i) individual and (ii) region-based, which we highlight using two case studies. For the individual execution mode, we present results from a city containing >10,000 buildings and show that more than half of the buildings are inefficient in one way or another indicating a significant potential from energy improvement measures. Additionally, we provide probable cause of inefficiency and find that 41%, 23.73%, and 0.51% homes have poor building envelope, heating, and cooling system faults, respectively. For the region-based execution mode, we show that WattScale can be extended to millions of homes in the U.S. due to the recent availability of representative energy datasets.

Dimensions of Control as Related to Work Organization, Stress, and Health

1989 ◽  
Vol 19 (3) ◽  
pp. 459-468 ◽  
Author(s):  
Gunnar Aronsson
Keyword(s):  
Management Strategies ◽  
Work Organization ◽  
Social Psychological ◽  
Research Perspectives ◽  
Control Concept ◽  
Production Techniques ◽  
Related Stress ◽  
The Individual ◽  
The Relationship ◽  
Stress And Health

The aim of this article is to examine how increased worker control-on the individual as well as on the collective level-may be a means to reduce the risk of work environment-related stress and diseases. Control is also an important element in socialization processes and in work reform activities directed to a democratization of working life. The concept of control connects a number of research perspectives. It deals with the individual and the collective level, as well as the relationship between them, and it may be a bridge between a social psychological and a psychobiological perspective. In this article, the author considers the control concept primarily from a stress perspective, but also examines how production techniques, legislation, and management strategies create the structure of control at work.

Exergy Analysis of Data Center Thermal Management Systems

2003 ◽  
Author(s):  
Amip J. Shah ◽  
Van P. Carey ◽  
Cullen E. Bash ◽  
Chandrakant D. Patel
Keyword(s):  
Thermal Management ◽  
Data Center ◽  
Data Centers ◽  
Exergy Analysis ◽  
Thermal Control ◽  
Management Systems ◽  
World Systems ◽  
Sample Data ◽  
Potential Applications ◽  
Temperature Ranges

Data centers today contain more computing and networking equipment than ever before. As a result, a higher amount of cooling is required to maintain facilities within operable temperature ranges. Increasing amounts of resources are spent to achieve thermal control, and tremendous potential benefit lies in the optimization of the cooling process. This paper describes a study performed on data center thermal management systems using the thermodynamic concept of exergy. Specifically, an exergy analysis has been performed on sample data centers in an attempt to identify local and overall inefficiencies within thermal management systems. The development of a model using finite volume analysis has been described, and potential applications to real-world systems have been illustrated. Preliminary results suggest that such an exergy-based analysis can be a useful tool in the design and enhancement of thermal management systems.

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