scholarly journals 403 Case Study of Measures for Energy Savings of Air-Conditioning Systems in Data Centers

2011 ◽  
Vol 2011.21 (0) ◽  
pp. 248-251
Author(s):  
Ari YOSHII ◽  
Yosuke UDAGAWA ◽  
Masahide YANAGI ◽  
Shisei WARAGAI ◽  
Keigo MATSUO ◽  
...  
Keyword(s):  
Air Conditioning ◽  
Data Centers ◽  
Energy Savings ◽  
Air Conditioning Systems

scholarly journals Dynamic simulation of indirect air conditioning systems with optimized computational time

2019 ◽  
Vol 111 ◽  
pp. 04042
Author(s):  
Nicolás Ablanque ◽  
Santiago Torras ◽  
Carles Oliet ◽  
Joaquim Rigola ◽  
Carlos-David Pérez-Segarra
Keyword(s):  
Air Conditioning ◽  
Energy Savings ◽  
Control Strategies ◽  
Model Potential ◽  
Hvac Systems ◽  
Object Oriented Programming ◽  
Computational Time ◽  
Air Conditioning System ◽  
Numerical Resolution ◽  
Air Conditioning Systems

The simulation of HVAC systems is a powerful tool to improve the energy efficiency in buildings. The modelling of such systems faces several obstacles due to both the physical phenomenology present and the numerical resolution difficulties. The present work is an attempt to develop a robust, fast, and accurate model for HVAC systems that can interact with the other relevant systems involved in buildings thermal management. The whole system model has been developed in the form of libraries under the Modelica language to exploit its advantageous characteristics: object-oriented programming, equationbased modelling, and handling of multi-physics. The global resolution is carried out dynamically so that not only steady-state predictions can be conducted but also control strategies can be studied over meaningful periods of time. This latter aspect is crucial for optimizing energy savings. The libraries include models for all the system individual components such as pumps, compressors or heat exchangers (operating with twophase flows and/or moist air) and also models assemblies to account for vapour compression units and liquid circuits. An illustrative example of an indirect air conditioning system is detailed in the present work in order to highlight the model potential.

Design for Sustainable Data Center Energy Use and Eco-Footprint

2010 ◽  
Author(s):  
Milton Meckler
Keyword(s):  
Data Center ◽  
Air Conditioning ◽  
Fossil Fuels ◽  
Energy Use ◽  
Data Centers ◽  
Ghg Emissions ◽  
High Energy ◽  
Operational Reliability ◽  
Energy Utilization ◽  
Air Conditioning Systems

What does remain a growing concern for many users of Data Centers is their continuing availability following the explosive growth of internet services in recent years, The recent maximizing of Data Center IT virtualization investments has resulted in improving the consolidation of prior (under utilized) server and cabling resources resulting in higher overall facility utilization and IT capacity. It has also resulted in excessive levels of equipment heat release, e.g. high energy (i.e. blade type) servers and telecommunication equipment, that challenge central and distributed air conditioning systems delivering air via raised floor or overhead to rack mounted servers arranged in alternate facing cold and hot isles (in some cases reaching 30 kW/rack or 300 W/ft2) and returning via end of isle or separated room CRAC units, which are often found to fight each other, contributing to excessive energy use. Under those circumstances, hybrid, indirect liquid cooling facilities are often required to augment above referenced air conditioning systems in order to prevent overheating and degradation of mission critical IT equipment to maintain rack mounted subject rack mounted server equipment to continue to operate available within ASHRAE TC 9.9 prescribed task psychometric limits and IT manufacturers specifications, beyond which their operational reliability cannot be assured. Recent interest in new web-based software and secure cloud computing is expected to further accelerate the growth of Data Centers which according to a recent study, the estimated number of U.S. Data Centers in 2006 consumed approximately 61 billion kWh of electricity. Computer servers and supporting power infrastructure for the Internet are estimated to represent 1.5% of all electricity generated which along with aggregated IT and communications, including PC’s in current use have also been estimated to emit 2% of global carbon emissions. Therefore the projected eco-footprint of Data Centers into the future has now become a matter of growing concern. Accordingly our paper will focus on how best to improve the energy utilization of fossil fuels that are used to power Data Centers, the energy efficiency of related auxiliary cooling and power infrastructures, so as to reduce their eco-footprint and GHG emissions to sustainable levels as soon as possible. To this end, we plan to demonstrate significant comparative savings in annual energy use and reduction in associated annual GHG emissions by employing a on-site cogeneration system (in lieu of current reliance on remote electric power generation systems), introducing use of energy efficient outside air (OSA) desiccant assisted pre-conditioners to maintain either Class1, Class 2 and NEBS indoor air dew-points, as needed, when operated with modified existing (sensible only cooling and distributed air conditioning and chiller systems) thereby eliminating need for CRAC integral unit humidity controls while achieving a estimated 60 to 80% (virtualized) reduction in the number servers within a existing (hypothetical post-consolidation) 3.5 MW demand Data Center located in southeastern (and/or southern) U.S., coastal Puerto Rico, or Brazil characterized by three (3) representative microclimates ranging from moderate to high seasonal outside air (OSA) coincident design humidity and temperature.

A multi-criteria decision making model for outsourcing maintenance services

Facilities ◽  
2015 ◽  
Vol 33 (3/4) ◽  
pp. 229-244 ◽  
Author(s):  
Mohammad A. Hassanain ◽  
Sadi Assaf ◽  
Abdul-Mohsen Al-Hammad ◽  
Ahmed Al-Nehmi
Keyword(s):  
Decision Making ◽  
Air Conditioning ◽  
Relative Weight ◽  
Equal Weight ◽  
Multi Criteria Decision Making ◽  
Content Type ◽  
Air Conditioning Systems ◽  
Decision Making Model ◽  
Outsourcing Decision

Purpose – The purpose of this paper is to present the development of a multi-criteria decision-making model for use by maintenance managers to consider before making a decision on outsourcing. Design/methodology/approach – Thirty-eight factors were identified for outsourcing maintenance services. These factors were grouped under six categories, namely: “strategic”, “management”, “technological”, “quality”, “economic” and “function characteristics”. The Analytic Hierarchy Process, as a multi-criteria decision-making model, was introduced and applied as an approach for maintenance managers in Saudi Arabian universities to consider before making a decision on outsourcing. A case study on the outsourcing decision of maintenance services of air-conditioning systems was carried out to apply the developed model. Findings – Data analysis indicated that all outsourcing decision groups of factors have almost equal weight, with the “quality” group of factors having the highest weight and the “technological” group of factors having the least weight. Further, the analysis indicated, in general, that the recommended decision for the maintenance managers is to outsource. However, an application of the developed model through a case study on the outsourcing of maintenance services of air-conditioning systems showed that the recommended action is not to outsource. Originality/value – The presented approach in this paper could be of practical benefit to maintenance managers in their decision making of whether or not to outsource maintenance services. The factors in the model were identified through a literature survey of research carried out in different countries. Therefore, the model could be applied in different settings, depending on the relative weight of the factors by the users.

scholarly journals Calculation of marine air conditioning systems based on energy savings

2017 ◽  
Vol 11 (21) ◽  
pp. 103
Author(s):  
Ricardo A. Lugo-Villalba ◽  
Mario Álvarez Guerra ◽  
Bienvenido Sarria López
Keyword(s):  
Air Conditioning ◽  
Energy Savings ◽  
Waste Heat ◽  
Cooling Capacity ◽  
Efficient Operation ◽  
Average Value ◽  
Economic Operation ◽  
International Policies ◽  
Need To Evaluate ◽  
Air Conditioning Systems

The development of ship propulsion in the areas of Economic Operation, Environmental Protection and Ship Efficiency (Triple E - Economy, Environment, Efficiency) is the comparison standard of the manufacturers of contemporary ships. The standard is based on the application of a more modern design of the diesel engines, the wide use of waste heat and the efficient operation of the ship.In accordance with the Economic Operation, the need to evaluate the design of air conditioning systems has been identified in order to determine the possible savings, which are represented by a decrease in fuel consumption, as a result of: the significant impact of this consumption in the operation of the ship, the current high costs of this energy, the periodic increase in the price of the same, and the international policies for the reduction of emissions to the atmosphere and preservation of the environment.By means of the energy diagnosis of the air conditioning system it is possible to determine the possible opportunities of energy saving during the operation of the ship.The results indicate that the thermal load and the cooling capacity required by the air conditioned spaces have a difference between their maximum and average value of 14%. This justifies the need to use a conditioning system with a variable volume of air supplied to the air conditioned space.

scholarly journals Validation of An Instrument to Know the Use of Smart Devices in Air Conditioners and Their Improvement in Energy Efficiency: Case Study in Ecuador

2021 ◽  
Vol 17 (04) ◽  
pp. 133
Author(s):  
Jorge Israel Anchundia-Santana ◽  
Julieta Evangelina Sánchez-Cano ◽  
Washington Garcia-Quilachamin ◽  
Evelyn Isabel Santana-Mantuano
Keyword(s):  
Energy Efficiency ◽  
Air Conditioning ◽  
Fossil Fuels ◽  
Online Survey ◽  
Smart Devices ◽  
Air Conditioners ◽  
Industrial Sectors ◽  
The Republic ◽  
Air Conditioning Systems

The constant growth of the world’s population has generated various changes in the use of the diversity of the resources provided to us by the planet. Considering that by properly managing energy in air conditioning systems correctly, it collaborates in the fight against climate change, reducing the excessive use of fossil fuels and, therefore, the emission of CO2 and other greenhouse gases, creating an environment of comfort in industrial sectors, businesses, companies, homes, among others. The objective of this research is to validate the instrument considering the information obtained about smart devices applied in air conditioning systems and their improvement in energy efficiency. The methodology applied consisted of a field study conducted through an online survey that was directed at 226 students and professionals from three provinces of the Republic of Ecuador. To validate the data obtained in the instrument, the exploratory factor analysis was performed also of the principal components in the last phase it was obtained in factor transformation matrix (0.986), which demonstrates the validity of the study. To apply the KMO test and Bartlett’s sphericity, the following ranges (≥0.6) y (<0.05) were considered respectively.

scholarly journals Experimental studies of energy efficiency of heat pump equipment for hot water supply and air conditioning systems in apartment buildings

2021 ◽  
Vol 937 (4) ◽  
pp. 042037
Author(s):  
Gregory Vasilyev ◽  
Victor Gornov ◽  
Marina Kolesova ◽  
Vitaliy Leskov ◽  
Victoria Silaeva ◽  
...  
Keyword(s):  
Water Supply ◽  
Heat Pump ◽  
Air Conditioning ◽  
Energy Savings ◽  
Experimental Studies ◽  
Hot Water ◽  
Apartment Buildings ◽  
Pump Equipment ◽  
Hot Water Supply ◽  
Air Conditioning Systems

Abstract Experimental studies of this article are aimed at solving the problem of reforming the housing and communal services of Russia through rational integration of non-traditional energy sources and secondary energy resources into the energy balance of buildings and structures. An important component of the work was the creation and development of industrial production of reliable competitive heat pump systems of a new generation, cogenerating heat energy and cold in an autonomous mode and providing energy savings of at least 50% due to the combined use of low-potential thermal energy of the soil, the atmospheric air and the exhaust air of ventilation systems for hot water supply and air conditioning systems of apartment buildings.

Experiences With Thermal Driven, Desiccant Assisted Air Conditioning Systems in Germany

2007 ◽  
Author(s):  
G. Schmitz ◽  
A. Joos ◽  
W. Casas
Keyword(s):  
Air Conditioning ◽  
Power Plants ◽  
Energy Savings ◽  
Measurement Data ◽  
Electricity Consumption ◽  
Heating System ◽  
Primary Energy ◽  
Dew Point ◽  
Water Evaporation ◽  
Air Conditioning Systems

During summer, the use of conventional electrically driven air conditioning systems often results in high electricity consumption. On the other hand, heat demand is very low, therefore heat from Combined Heat and Power plants (CHP) or from solar collectors can not be used. Thermal driven desiccant assisted air conditioning systems offer the possibility to shift energy requirements from electricity to heat. Furthermore, as sorptive pre-drying air doesn’t require cooling under dew point for dehumidifying nor any subsequent heating, cold sources at higher temperatures (e.g. 18°C) can be used for cooling. Within the scope of research projects, different demonstration plants for office buildings and a private bungalow were built, where the operations were evaluated by the Hamburg University of Technology. One plant combines a desiccant wheel with a small (5 kWel) gas driven co-generation plant. Instead of an electric chiller or a water evaporation system (desiccant evaporating cooling), borehole heat exchangers in combination with a radiant floor heating system were used for cooling in summer. In this paper, performance comparisons with conventional systems based on numerical simulations and measurement data are shown, including a cost analysis. It is found that the combination of desiccant wheels and earth energy systems offers considerable energy savings compared to conventional electric systems. The operation of such systems is also cost-effective. It can lead to a reduction of up to 28% of primary energy consumption in a whole year compared to a conventional A/C system.

scholarly journals Influence of Indoor Climate on Employees in Office Buildings—A Case Study

2020 ◽  
Vol 12 (14) ◽  
pp. 5569 ◽  
Author(s):  
Peter Kapalo ◽  
Silvia Vilčeková ◽  
Ľudmila Mečiarová ◽  
Florin Domnita ◽  
Mariusz Adamski
Keyword(s):  
Air Quality ◽  
Air Conditioning ◽  
Subjective Evaluation ◽  
Research Work ◽  
Co2 Concentration ◽  
Office Buildings ◽  
Indoor Climate ◽  
Office Rooms ◽  
Air Conditioning Systems

The presented research work is aimed at investigation of the influence of indoor environmental conditions on employees in office buildings. Monitoring of carbon dioxide, temperature, relative humidity and pulse, as well as subjective evaluation, was carried out in three office rooms where air conditioning systems ensured the required amount of fresh air. Investigation showed that in two offices (A and B), the amount of fresh air did not comply with EN 15251:2017. The concentration of CO2 in office A was above 1000 ppm for 72% of the total length of stay. Respondents confirmed fatigue and headaches. In offices A and B, where CO2 concentration was around 1000 ppm, people with a weight of up to 70 kg experienced a significant increase in air temperature as well as odor. Persons with weight higher than 75 kg experienced a slight decrease in air quality. In office C, where CO2 concentration was around 800 ppm, respondents reported a slight decrease in air quality. According to pulse monitoring, it can be stated that in an office where there is an insufficient supply of fresh air, the pulse of a person falls or only slightly rises. A decrease in pulses may indicate the attenuation or stunning of people caused by poor air quality.

Sign in / Sign up

Export Citation Format

Share Document