HVAC Economizers 101 Principles and Operations for Efficiency
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Consider Installing a Condensing Economizer, Energy Tips
ADVANCED MANUFACTURING OFFICE Energy Tips: STEAM Steam Tip Sheet #26A Consider Installing a Condensing Economizer Suggested Actions The key to a successful waste heat recovery project is optimizing the use of the recovered energy. By installing a condensing economizer, companies can im- ■■ Determine your boiler capacity, prove overall heat recovery and steam system efficiency by up to 10%. Many average steam production, boiler applications can benefit from this additional heat recovery, such as district combustion efficiency, stack gas heating systems, wallboard production facilities, greenhouses, food processing temperature, annual hours of plants, pulp and paper mills, textile plants, and hospitals. Condensing economiz- operation, and annual fuel ers require site-specific engineering and design, and a thorough understanding of consumption. the effect they will have on the existing steam system and water chemistry. ■■ Identify in-plant uses for heated Use this tip sheet and its companion, Considerations When Selecting a water, such as boiler makeup Condensing Economizer, to learn about these efficiency improvements. water heating, preheating, or A conventional feedwater economizer reduces steam boiler fuel requirements domestic hot water or process by transferring heat from the flue gas to the boiler feedwater. For natural gas-fired water heating requirements. boilers, the lowest temperature to which flue gas can be cooled is about 250°F ■■ Determine the thermal to prevent condensation and possible stack or stack liner corrosion. requirements that can be met The condensing economizer improves waste heat recovery by cooling the flue through installation of a gas below its dew point, which is about 135°F for products of combustion of condensing economizer. -
Page 1 OPTIMAL ENERGY MANAGEMENT of HVAC
Page 1 OPTIMAL ENERGY MANAGEMENT OF HVAC SYSTEMS BY USING EVOLUTIONARY ALGORITHM Session Number: CIB T2S5 Authors Fong K F, BEng, MSc, CEng, MCIBSE, MHKIE, MASHRAE Hanby V I, BSc, PhD, CEng, MInstE, MCIBSE Chow T T, PhD, CEng, MIMechE, MCIBSE, FHKIE, MASHRAE Abstract The available plant and energy simulation packages become robust and user-friendly, and this is the major reason that they are so popular even in the consultancy fields in these few years. In fact, these plant and energy simulation packages can be widely adopted in studying different alternatives of the operation of HVAC and building services systems. Since there are many parameters involved in different equipment and systems, one of the useful areas of studies is to optimize the essential parameters in order to provide a satisfactory solution for design or operation in terms of efficient and effective facilities management. Therefore in this paper, the simulation-optimization approach is proposed for effective energy management of HVAC systems. Due to the complexity of the HVAC systems, which commonly include the refrigeration, water and air side systems, it is necessary to suggest optimal conditions for different operation according to the dynamic cooling load requirements throughout a year. A simulation-EA coupling suite has been developed by using the metaheuristic skill, and the evolutionary algorithm can be effectively used to handle the discrete, non-linear and highly constrained characteristics of the typical HVAC and building services optimization problems. The effectiveness of this simulation-EA coupling suite has been demonstrated through the establishment of the monthly optimal reset scheme of the chilled water supply temperature of a local central chiller plant. -
Heat Transfer Model of a Rotary Compressor S
Purdue University Purdue e-Pubs International Compressor Engineering Conference School of Mechanical Engineering 1992 Heat Transfer Model of a Rotary Compressor S. K. Padhy General Electric Company Follow this and additional works at: https://docs.lib.purdue.edu/icec Padhy, S. K., "Heat Transfer Model of a Rotary Compressor" (1992). International Compressor Engineering Conference. Paper 935. https://docs.lib.purdue.edu/icec/935 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. Complete proceedings may be acquired in print and on CD-ROM directly from the Ray W. Herrick Laboratories at https://engineering.purdue.edu/ Herrick/Events/orderlit.html HEAT TRANSFER MODEL OF A ROTARY COMPRESSOR Sisir K. Padhy General Electric C_ompany Appliance Park 5-2North, Louisville, KY 40225 ABSTRACT Energy improvements for a rotary compressor can be achieved in several ways such as: reduction of various electrical and mechanical losses, reduction of gas leakage, better lubrication, better surface cooling, reduction of suction gas heating and by improving other parameters. To have a ' better understanding analytical/numerical analysis is needed. Although various mechanical models are presented to understand the mechanical losses, dynamics, thermodynamics etc.; little work has been done to understand the compressor from a heat uansfer stand point In this paper a lumped heat transfer model for the rotary compressor is described. Various heat sources and heat sinks are analyzed and the temperature profile of the compressor is generated. A good agreement is found between theoretical and experimental results. NOMENCLATURE D, inner diameter D. -
Ene04 Low Carbon Design Low and Zero Carbon Technologies
Ene04 Low carbon design Low and zero carbon technologies Actions: i. Implement LZC (low and zero carbon) technologies in-line with the LZC feasibility study ii. Implement passive design measures and free cooling technologies in line with the previous analysis undertaken Recognised local LZC technologies Technologies eligible to contribute to achieving the criteria must produce energy from renewable sources and meet all other ancillary requirements as defined by Directive 2009/28/EC. Local does not have to mean on site – community schemes near to the site can be used as a way of demonstrating compliance. The following requirements must also be met: 1. There must be a direct supply of energy produced to the building under assessment. 2. Technologies under 50 kWe or 45 kWth must be certified by a Microgeneration Certification Scheme (MCS), or equivalent, and installed by MCS (or equivalent) certified installers. 3. Combined heat and power (CHP) schemes above 50 kWe must be certified under the CHPQA standard. CHP schemes fuelled by mains gas are eligible to contribute to performance against this issue. 4. Heat pumps can only be considered as a renewable technology when used in heating mode. Refer to Annex VI of Directive 2009/28/EC for more detail on accounting for energy from heat pumps. 5. Where MCS or CHPQA certification is not available, the design team must investigate the availability of alternative accreditation schemes in line with the Directives listed above, or an equivalent country or regional directive or standard. Where an accreditation scheme exists, it should be used for the purpose of verifying compliance of the specified LZC technology. -
Why Does the Wisconsin Boiler and Pressure Vessel Code, 636 41
Why does the Wisconsin Boiler and Pressure Vessel Code, SPS 341, regulate air compressors? By Industry Services Division Boiler and Pressure Vessels Program Almost everyone forms a definite picture in their mind when they hear the term “air compressor.” They probably think of a steel tank of some shape and dimension, with an electric motor, and an air pump mounted on top of the tank. To better understand the requirements of the Wisconsin Boiler Code, SPS 341, pertaining to air compressors, we need to have some common terminology. If a person wanted to purchase an “air compressor” at a hardware or home supply store, they would certainly be offered the equipment described above, consisting of three separate mechanical devices; the motor, the pump, and the storage tank. First, there is an electric motor, used to provide power to the device that pumps air to high pressure. This pumping device is the only part of the unit that is properly called an "air compressor." The compressor delivers high-pressure air to the third and final part of the mechanical assembly, the air storage tank; commonly called a pressure vessel. Because the pressure vessel receives pressurized air, this is the only part of the device described above that is regulated SPS 341. SPS 341 regulates pressure vessels when the pressure vessel's volume capacity is 90 gallons (12 cubic feet) or larger, and the air pressure is 15 pounds per square inch or higher. A typical pressure vessel of this size would be 24 inches in diameter and 48 inches long. In industrial settings, it is common practice to mount very large air compressors in a separate location from the pressure vessels. -
Performance Comparison Between an Absorption-Compression Hybrid Refrigeration System and a Double-Effect Absorption Refrigeration Sys-Tem
Available online at www.sciencedirect.com ScienceDirect Available online at www.sciencedirect.com Procedia Engineering 00 (2017) 000–000 ScienceDirect www.elsevier.com/locate/procedia Procedia Engineering 205 (2017) 241–247 10th International Symposium on Heating, Ventilation and Air Conditioning, ISHVAC2017, 19- 22 October 2017, Jinan, China Performance Comparison between an Absorption-compression Hybrid Refrigeration System and a Double-effect Absorption Refrigeration Sys-tem Jian Wang, Xianting Li, Baolong Wang, Wei Wu, Pengyuan Song, Wenxing Shi* Beijing Key Laboratory of Indoor Air Quality Evaluation and Control, Department of Building Science, Tsinghua University, Haidian District, Beijing 100084, China Abstract Conventional absorption refrigeration systems (ARSs), which are mainly driven by heat, have a competitive primary energy efficiency (PEE) compared with chillers driven by electricity. In the typical ARS, a large quantity of high-temperature heat is supplied into the generator, while a substantial amount of low-temperature heat is rejected to the environment from the condenser, it’s a huge waste. In order to decrease the input heat for generator and enhance the performance of conventional ARS, a kind of absorption-compression hybrid refrigeration system recovering condensation heat for generation (RCHG-ARS) was ever proposed. In the present study, the models of both RCHG-ARS and double-effect absorption refrigeration system (DEARS) are established, and the effects of different parameters on them are simulated and compared with each other. As a conclusion, the PEE of RCHG-ARS can be 29.0% higher than that of DEARS, and RCHG-ARS has a wider working conditions than DEARS due to the existence of the compressor. -
Bendix® Ba-922® Sae Universal Flange Air Compressor
compressors BENDIX® BA-922® SAE UNIVERSAL FLANGE AIR COMPRESSOR High output compressed air generation for ultra demanding commercial & industrial applications. Experience Counts Ideal for niche industrial, agricultural, and For generations, Bendix Commercial Vehicle Systems (Bendix CVS) has petroleum applications, the universal flange been leading the way in air charging system experience and expertise. model . More fleets specify our hard-working products and systems than any other. Features an adapter mount to meet SAE J744 Bendix CVS continues its legacy of quality, reliability and durability with hydraulic pump, engine & motor mounting, a next generation high-performing, energy-saving compressor option – and drive dimensions standards; the Bendix® BA-922® SAE Universal Flange compressor. Can be mounted at several different angles An Ideal Solution For A Wide Range Of depending on physical constraints and application necessities; and Unique Applications Utilizing a standard SAE B Flange, and a 15-tooth BB spline for strength, Is driven by an engine PTO, hydraulic motor, the Bendix® BA-922® SAE compressor is designed to address a wide or electric motor. Option for belt drive as well. variety of commercial and industrial applications. Its clock-able front adapter allows the compressor to be easily mounted in several different positions depending on your requirement. Building On The Power Of The Bendix® BA-922® Compressor: High Air Delivery A dependable workhorse, the Bendix® BA-922® compressor provides maximum air delivery even at low speeds. Its high-output, two-cylinder design supplies 32 cfm (cubic feet per minute) displacement at 1,250 rpm (revolutions per minute). Power like this delivers the ability to recharge the system quickly and efficiently – even at low speeds – making it ideal for more demanding brake system applications. -
Use Feedwater Economizers for Waste Heat Recovery, Energy Tips
ADVANCED MANUFACTURING PROGRAM Energy Tips: STEAM Steam Tip Sheet #3 Use Feedwater Economizers for Waste Heat Recovery Suggested Actions ■■ Determine the stack temperature A feedwater economizer reduces steam boiler fuel requirements by transferring after the boiler has been tuned heat from the flue gas to incoming feedwater. Boiler flue gases are often to manufacturer’s specifications. rejected to the stack at temperatures more than 100°F to 150°F higher than The boiler should be operating the temperature of the generated steam. Generally, boiler efficiency can at close-to-optimum excess be increased by 1% for every 40°F reduction in flue gas temperature. By air levels with all heat transfer recovering waste heat, an economizer can often reduce fuel requirements by 5% surfaces clean. to 10% and pay for itself in less than 2 years. The table provides examples of ■■ Determine the minimum the potential for heat recovery. temperature to which stack gases Recoverable Heat from Boiler Flue Gases can be cooled subject to criteria such as dew point, cold-end Recoverable Heat, MMBtu/hr corrosion, and economic heat Initial Stack Gas transfer surface. (See Exhaust Temperature, °F Boiler Thermal Output, MMBtu/hr Gas Temperature Limits.) 25 50 100 200 ■■ Study the cost-effectiveness of installing a feedwater economizer 400 1.3 2.6 5.3 10.6 or air preheater in your boiler. 500 2.3 4.6 9.2 18.4 600 3.3 6.5 13.0 26.1 Based on natural gas fuel, 15% excess air, and a final stack temperature of 250˚F. Example An 80% efficient boiler generates 45,000 pounds per hour (lb/hr) of 150-pounds-per-square-inch-gauge (psig) steam by burning natural gas. -
Demand-Response Management of a District Cooling Plant of a Mixed Use City Development
Demand-Response Management of a District Cooling Plant of a Mixed Use City Development Segu Madar Mohamed Rifai Master of Science Thesis KTH - Royal Institute of Technology School of Industrial Engineering and Management Department of Energy Technology SE-100 44 STOCKHOLM Thesis Registration No.: EGI- 2012-011MSC Title: Demand-Response Management of a District Cooling Plant of a Mixed Use City Development. SEGU MADAR MOHAMED RIFAI Student Number: 731222 A-315 Approved Examiner Supervisor at KTH Date: 05/06/2012 Prof. Björn Palm Dr. Samer Sawalha Local Supervisor Dr. Hari Gunasingam Commissioner Contact person i | P a g e Abstract Demand for cooling has been increasing around the world for the last couple of decades due to various reasons, and it will continue to increase in the future particularly in developing countries. Traditionally, cooling demand is met by decentralised electrically driven appliances which affect energy, economy and environment as well. District Cooling Plant (DCP) is an innovative alternative means of providing comfort cooling. DCP is becoming an essential infrastructure in modern city development owning to many benefits compared to decentralized cooling technology. Demand Response Management (DRM) is largely applied for Demand Side management of electrical grid. Demand of electrical energy is closely connected with the demand of alternative form of energy such as heating, cooling and mechanical energy. Therefore, application of DR concept should be applied beyond the electrical grid; in particular, it could be applied to any interconnected district energy systems. District Cooling Plant is one of a potential candidate and Demand Response management solutions can be applied to DCP for sustainable operation. -
Free Cooling – Outside Air Economizer White Paper #11
FREE COOLING – OUTSIDE AIR ECONOMIZER WHITE PAPER #11 It’s like opening a window when it’s hot inside and cool outside. How much does it save? The easy answer is ‘it depends.’ To really find out, read further. You’ll see there are a lot of factors. Like all heat recovery concepts, a pre-requisite for success is to have the free heat (or free cooling) available at the same location and time as there is a need for it. The free heat in Atlanta has no practical use in Alaska because they are too far apart. Likewise, free cooling from outdoors doesn’t provide any value unless it is warm indoors at that time. Balance Temperature Buildings are like boxes. They have thermal losses and gains through the shell (envelope), and they also have appliances and activities inside that generate heat. See Figure 1. There will be a point where the envelope loss just matches the internal heat gains and neither heating nor cooling is required; above this ‘balance temperature’, cooling will be required. Source: Commercial Energy Auditing Reference Handbook, 3e Doty,S., Fairmont Press. Figure 1. Thermal Balance Temperature FREE COOLING – OUTSIDE AIR ECONOMIZER White Paper What is your building’s balance temperature? A building’s thermal balance temperature can be estimated with a method called regression, but there are also clues. See Table 1. If there is a lot of heat-producing equipment inside, the building becomes self- heating and will include hours in cooling mode when it is cold outside. Opportunity! If the heating and cooling load is mostly from envelope (not a lot of equipment), the balance point will be higher which means it probably won’t be hot inside while it is cold outside. -
ASHRAE Position Document on Filtration and Air Cleaning
ASHRAE Position Document on Filtration and Air Cleaning Approved by ASHRAE Board of Directors January 29, 2015 Reaffirmed by Technology Council January 13, 2018 Expires January 23, 2021 ASHRAE 1791 Tullie Circle, NE • Atlanta, Georgia 30329-2305 404-636-8400 • fax: 404-321-5478 • www.ashrae.org © 2015 ASHRAE (www.ashrae.org). For personal use only. Additional reproduction, distribution, or transmission in either print or digital form is not permitted without ASHRAE's prior written permission. COMMITTEE ROSTER The ASHRAE Position Document on Filtration and Air Cleaning was developed by the Society's Filtration and Air Cleaning Position Document Committee formed on January 6, 2012, with Pawel Wargocki as its chair. Pawel Wargocki, Chair Dean A. Saputa Technical University of Denmark UV Resources Kongens Lyngby, Denmark Santa Clarita, CA Thomas H. Kuehn William J. Fisk University of Minnesota Lawrence Berkeley National Laboratory Minneapolis, MN Berkeley, CA H.E. Barney Burroughs Jeffrey A. Siegel Building Wellness Consultancy, Inc. The University of Toronto Johns Creek, GA Toronto, ON, Canada Christopher O. Muller Mark C. Jackson Purafil Inc. The University of Texas at Austin Doraville, GA Austin, TX Ernest A. Conrad Alan Veeck BOMA International National Air Filtration Association Washington DC Virginia Beach, VA Other contributors: Dean Tompkins Madison, WI for his contribution on photocatalytic oxidizers Paul Francisco, Ex-Officio Cognizant Committee Chair Environmental Health Committee University of Illinois Champaign, IL ASHRAE is a registered trademark in the U.S. Patent and Trademark Office, owned by the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. © 2015 ASHRAE (www.ashrae.org). For personal use only. -
Energy and Exergy Analysis of Data Center Economizer Systems
San Jose State University SJSU ScholarWorks Master's Theses Master's Theses and Graduate Research Spring 2011 Energy and Exergy Analysis of Data Center Economizer Systems Michael Elery Meakins San Jose State University Follow this and additional works at: https://scholarworks.sjsu.edu/etd_theses Recommended Citation Meakins, Michael Elery, "Energy and Exergy Analysis of Data Center Economizer Systems" (2011). Master's Theses. 3944. DOI: https://doi.org/10.31979/etd.bf7d-khxd https://scholarworks.sjsu.edu/etd_theses/3944 This Thesis is brought to you for free and open access by the Master's Theses and Graduate Research at SJSU ScholarWorks. It has been accepted for inclusion in Master's Theses by an authorized administrator of SJSU ScholarWorks. For more information, please contact [email protected]. ENERGY AND EXERGY ANALYSIS OF DATA CENTER ECONOMIZER SYSTEMS A Thesis Presented to The Faculty of the Department of Mechanical and Aerospace Engineering San José State University In Partial Fulfillment of the Requirements for the Degree Master of Science By Michael E. Meakins May 2011 © 2011 Michael E. Meakins ALL RIGHTS RESERVED The Designated Thesis Committee Approves the Thesis Titled ENERGY AND EXERGY ANALYSIS OF DATA CENTER ECONOMIZER SYSTEMS by Michael E. Meakins APPROVED FOR THE DEPARTMENT OF MECHANICAL AND AEROSPACE ENGINEERING SAN JOSÉ STATE UNIVERSITY May 2011 Dr. Nicole Okamoto Department of Mechanical and Aerospace Engineering Dr. Jinny Rhee Department of Mechanical and Aerospace Engineering Mr. Cullen Bash Hewlett Packard Labs ABSTRACT ENERGY AND EXERGY ANALYSIS OF DATA CENTER ECONOMIZER SYSTEMS By Michael E. Meakins Electrical consumption for data centers is on the rise as more and more of them are being built.