Existing and Emerging Energy Efficient Gas Technologies

Transcription

1 Existing and Emerging Energy Efficient Gas Technologies Gas Technology Institute Copyright 2015 by Gas Technology Institute (GTI) No portion of this material may be reproduced without the expressed written consent of GTI

2 History 2 Slide Courtesy of ENER553 Module 7: ASHRAE 90.1 D Cohen

3 U.S. Commercial Energy Code History of efficiency improvements 23% 5% 18% Slide Courtesy of ENER553 Module 7: ASHRAE 90.1 D Cohen 3

4 Outline I. Commercial ERVs II. Boilers 1. Introduction to Boilers 2. Boiler Tuning 3. Boilers Controls 4. High Eff. Boilers 5. Boiler Economizer Technologies III. Industrial Scale High Eff. Water Heating IV. On-Site Gen 1. CHP Industrial Campus Application (GT CHP) 2. The Emerging Technology of Microturbine CHP 4

5 I. Commercial ERVs

6 Background on IAQ Issues 6

7 What is Good Indoor Air Quality? >Not Well Defined Technical Description: air toward which a majority of occupants express no dissatisfaction in which there are not likely to be contaminants known to pose a health risk. Very Vague This is Why Standards are So Important 7

8 Source Control >Indoor Air Quality Problems May Be Gases or Dusts from Specific Sources Unhealthy Objectionable 8 8 Picture Courtesy of Home Ventilation Institute

9 Common Sources >Mildew >New Furnishings >Construction Materials and Adhesives >Cleaners and Chemicals Picture Courtesy of Canada Mortgage and Housing Corporation. 9

10 Why has IAQ Become a Major Issue in Recent Years? >Trends Making IAQ Issues More Severe Greater Use of Adhesives in Construction Windows Largely Sealed Increased Rates of Childhood Asthma (Schools) Greater Customer Sensitivity 10

11 What are the Major Ways to Improve Indoor Air Quality? >Source Control Keeping Pollutant Source Out >Fresh Air Dilution Reducing the concentration of contaminants >Re-circulated Air Cleaning Removing harmful contaminants from the air 11

12 Limits of the Builders Influence on Source Control >Builder has No Control Over What a Owner May Bring into the Building >Some Sources Grow Later Mold and Mildew >Builder Cannot Depend on Source Control to Limit Liability 12

13 Re-circulated Air Cleaning Not a Complete Answer >Particulates Small airborne particles or drops Filtration may/may not sufficient >VOC s - Volatile Organic Compounds Present as a Gas Ventilation is the Common Solution Filtration Technologies are Uncommon >Also Need to Rid Building of CO2 Build-Up 13

14 Fresh Air Dilution >Only Code Approved Way to Handle Indoor Air Quality Standards and Issues >Gives the Builder Control Over IAQ Issues By Providing for Fresh Air Introduction and Exhaust Ventilation in the Original Design 14

15 Why Not Let Buildings Leak? Why is Ventilation Better than Infiltration? Unlike Infiltration, Ventilation is: >Conditioned Not Cold or Hot Outdoor Air >Filtered >Distributed Thru the Building >Today Can be Controllable Provided Only as Needed Provided Only in the Amount Required 15

16 Outside Air Standard 62 16

17 Ventilation Heat Exchangers 17

18 IAQ and Energy Conservation ASHRAE 62 Objective: Provide Outside air to resolve IAQ problems; increase energy consumption ASHRAE 90.1 Objective: reduce energy consumption to support efficiency 18 Picture Courtesy of Eric Van Uytfanck, Venmar CES Corporation, 2008 (Ref

19 90.1 Req. Exhaust Air Energy Recovery 19

20 Ventilation System with HX 20 Picture Elements of ASHRAE 62.1

21 ERV Systems 21 Picture Courtesy of Building Science Corporation

22 Types of Heat Recovery HX Plate heat exchangers Sensible 50 70% Heat Pipes Sensible 45-50% Heat Wheels 65 80% Total Eff. 22 Picture Courtesy of Eric Van Uytfanck, Venmar CES Corporation, 2008 (Ref

23 Air-to-Air Plate Exchangers >Sensible Efficiencies : 50-70% Available Materials: Aluminum, Polypropylene, Stainless >Large Typically Smaller Flow Systems or Residential 23 Picture Courtesy of Eric Van Uytfanck, Venmar CES Corporation, 2008 (Ref

24 Operation of Plate HX Picture Courtesy of Popular Mechanics

25 Theory of Operation-Plate Heat Exchanger > Consists of a Stack of Plates with Air Passages Between Each Plate > Two Air Flows Travel Thru Every OTHER Passage > Provides a Large Surface for Heat to Pass from One Airflow to the Other 25 Picture Courtesy of Popular Mechanics

26 Heat Pipe Heat Exchangers Sensible Eff % Process Applications 0% contamination Largely Industrial 26 Picture Courtesy of Eric Van Uytfanck, Venmar CES Corporation, 2008 (Ref

27 Heat Exchange Wheel Efficiencies: 65-80% Minor Cross- Contamination Compact Suitable for Large Commercial Buildings 27 Picture Courtesy of Eric Van Uytfanck, Venmar CES Corporation, 2008 (Ref

28 Heat Wheel Operation > Wheel rotates between warm exhaust air and cold outdoor air, carrying heat. > Some leakage of air is inevitable as clearances are required between the rotor and the housing. > Capable of recovering up to 95% of exhaust air heat. 28 Picture Courtesy of Popular Mechanics

29 Heat Exchange Wheel 29 Picture Courtesy of Munters

30 Heat Wheels 30 Picture Courtesy of Eric Van Uytfanck, Venmar CES Corporation, 2008 (Ref

31 Close-Up of a Heat Wheel > Heat is transferred from a hot gas to a cold one via a rotating wheel of densely packed metal sheets, called elements > As the wheel turns, the heated elements move into the cool outdoor air stream, increasing its temperature 31 Picture Courtesy of Popular Mechanics

32 Desiccant Dehumidification for Ventilation 32

33 Desiccant Dehumidification for Ventilation >Ventilation Can Carry High Levels of Humidity >High Ventilation Needs Can Swamp Conventional Air Conditioning >Add Desiccant to Heat Recovery Wheel to Exchange Moisture 33

34 Fresh Air Also Brings Humidity 34 Picture Courtesy of Eric Van Uytfanck, Venmar CES Corporation, 2008 (Ref

35 Enthalpy Wheel - Add a Desiccant Coating to a Heat Exchange Wheel Total Efficiencies: 65-80% (Sensible & Latent) Latent heat transfer made through Dessicants Molecular sieve Silica Gel 35 Picture Courtesy of Eric Van Uytfanck, Venmar CES Corporation, 2008 (Ref

36 Passive Desiccant Dehumidification Process (Summer Operation) 36 Picture Courtesy of Munters

37 Desiccant Wheels 37 Picture Courtesy of Lew Harriman: Commercial Desiccant Systems Symposium, Tivoli,

38 Active Desiccant Dehumidification > Active Vs. Passive Desiccant System >Active Desiccant System Uses Heated Air for Regeneration >Much More Moisture Removal >Controllable 38 Picture Courtesy of Lew Harriman: Commercial Desiccant Systems Symposium, Tivoli,

39 Active Desiccant Dehumidification 39 Picture Courtesy of Lew Harriman: Commercial Desiccant Systems Symposium, Tivoli,

40 Application Typical DOAS configuration 40 Picture Courtesy of Lew Harriman: Commercial Desiccant Systems Symposium, Tivoli,

41 Packaged System Layout Ventilation Unit 41 Picture Courtesy of Lew Harriman: Commercial Desiccant Systems Symposium, Tivoli,

42 References >Eric Van Uytfanck, Eng, Energy Recovery Technologies, Venmar CES 2008 >Task Residential Ventilation Systems Training, The National Center for Energy Management and Building Technology 42

43 Dedicated Outdoor Air Systems (DOAS) and Demand Control Ventilation (DCV) 43

44 Dedicated Outdoor Air Systems (DOAS) >To Better Control Ventilation New High Efficiency Buildings Separate Ventilation from the Cooling System >Allows Independent Control 44

45 Dedicated Outdoor Air Systems (DOAS) 45 Picture Courtesy of Building Sciences.com

46 46

47 DOAS Air Pretreatment 47 Slide Courtesy of Stanley A. Mumma, Penn State

48 ASHRAE HQ, Atlanta, GA DOAS unit 48 Slide Courtesy of Stanley A. Mumma, Penn State

49 49 Slide Courtesy of Stanley A. Mumma, Penn State

50 Demand Control Ventilation >Ventilation removes objectionable pollutants >Ventilation also removes CO2 and supplies fresh oxygen >All ventilation systems elevate CO2 levels above outdoor levels >Today we can use this elevated level as a point of ventilation control >Most Important Energy Issue Turns the Ventilation Down of Off When Not Needed 50

51 CO2 CO2 Concentrations (ppm) (ppm) How Much CO2?? Elevated CO2 Levels in Any System 3,000 3,000 2,500 2,500 2,000 CO 2 Levels Will Build And Level Off At The Point Were CO 2 Produced By People Is In Equilibrium With Outside Air Ventilated Into The Space CO 2 Levels Will Build And Level Off At The Point Were CO 2 Produced By People Is In Equilibrium With Outside Air Ventilated Into The Space 5 cfm/person 5 cfm/person 2,000 1, , , , :00 1:00 2:00 3:00 4:00 5:00-0:00 1:00 2:00 Time (Hours) 3:00 4:00 5:00 Time (Hours) 51

52 Demand-Controlled Ventilation (DCV) 52

53 Demand-Controlled Ventilation (DCV) >The most important feature in DCV is that it automatically turns off when not needed >Large energy savings opportunity 53

54 II. Boilers

55 !!. Boilers 1. Introduction to Boilers 2. Boiler Tuning 3. Boilers Controls 4. High Eff. Boilers 5. Boiler Economizer Technologies 55

56 1. Introduction to Boilers

57 Learning Objective >Develop recognition of basic boiler types and auxiliary equipment for both commercial and industrial applications as well as gain familiarity with boiler terms >Focus is on recognition and terminology 57

58 Overview >Types of Boilers >Boiler Terms >Boiler Codes >Large Boiler Accessories >Small Boilers >Hydronic Accessories 58

59 Types of Boilers 59

60 - Types of Boilers Types of Boilers >Boiler: Device for Generating Steam or Hot Water >2 Major Configurations Fire-Tube Boiler Water -Tube Boiler >Delivery Types Packaged Boiler Field Erected Boiler 60

61 - Types of Boilers Firetube Vs Water Tube >Watertube Boiler Large Box Filled with Combustion Gases Water is in Vertical Tubes in Which it Boils >Firetube Boiler Large Tank of Water Immersed Tubes Carry Combustion Gases 61 Picture Courtesy of HowStuffWorks.com

62 - Types of Boilers Firetube Boiler 62 Picture Courtesy of Cleaver Brooks

63 - Types of Boilers Firetube Cut Away 63 Picture Courtesy of Cleaver Brooks

64 - Types of Boilers Fire Tube Detail 64 Picture Courtesy of Cleaver Brooks

65 3 Pass Firetube Boiler Steam Boiler Shown 65 Picture Courtesy of Spirax Sarco

66 3 Pass Firetube Boiler Hot Water (Hydronic) Boiler Shown 66 Picture Courtesy of Spirax Sarco

67 Wetback - 2 Pass 67 Picture Courtesy of Spirax Sarco

68 Dryback - 2 Pass 68 Picture Courtesy of Spirax Sarco

69 Firetube Boiler on Steam 69 Picture Courtesy of Water Tube Boiler System Design.org

70 Hospital Firetube Steam Plant 70 Picture Courtesy of UIC Energy Resource Center

71 - Types of Boilers Watertube Boiler 71 Picture Courtesy of Cleaver Brooks

72 Watertube Cut-Away - Types of Boilers 72 Picture Courtesy of Cleaver Brooks

73 Watertube Cut-Away - Types of Boilers 73 Picture Courtesy of Cleaver Brooks

74 - Types of Boilers Watertube Boiler Bank Hydronic Boilers Shown Picture Courtesy GTI 74 Picture Courtesy GTI

75 - Types of Boilers Packaged Boiler Brought to the Site Complete Including Burners and Controls Most Space Conditioning Applications 75 Picture Courtesy of Cleaver Brooks

76 - Types of Boilers Field Erected Boilers Generally Very Large Capacity Boilers Brought to the Site in Pieces and Constructed Central Plant and Power Applications 76 Picture Courtesy of Cleaver Brooks

77 Field Erected Boilers Can be Very Large and Burn a Variety of Fuels - Types of Boilers 77 Picture Courtesy of Babcock and Wilcox

78 - Types of Boilers Field Erected Boilers Typical of Larger Industrial 78 Picture Courtesy of Babcock and Wilcox

79 Field Erected Boilers 79 Picture Courtesy of Babcock and Wilcox

80 - Boiler Accessories Burners >Packaged Boilers will Come Equipped >Generally Supplied by Third Party Power Flame: Largest in North American >Forced Draft Pre-Mixed Burner Complete with Blower Motor and Controls Variable Combustion Rate Turn-Down: How Far Burner will Go Down in Firing Rate At Least 50% >Burner will Have Separate Name Plate 80

81 - Boiler Accessories Burners 81 Picture Courtesy of UIC Energy Resource Center

82 - Boiler Accessories Burners 82 Picture Courtesy of Weishaupt

83 Boiler Terms 83

84 Terms >Boiler Horsepower Old Term 1 Boiler HP = 34.5 lbs./hr. of low pressure steam or 33,472 Btu/hr. Output >Number of Passes Number of Times Flue Gas Travels the Length of the Boiler before Reaching the Vent 84

85 Pressure >Gauge Pressure Above Atmospheric Pressure Noted as psig >Absolute Pressure Above a Complete Vacuum - Noted as psia psia psig 15 or Bar abs Bar guage 1 >If steam is pressurized to 5 pounds per square inch above surrounding atmosphere, it is at 5 psig and at 20 psia 85

86 Watertube Drums >Steam Drum Separates Steam from Hot Water >Mud Drum Collects Solids Falling Out of Water as it is Heated 86 Picture Courtesy of Cleaver Brooks Boiler

87 Watertube Drums 87 Picture Courtesy of Spirax Sarco

88 Blowdown Steam Only >Dumping Water from a Steam System to keep Solids in the Water from Accumulating >Continuous - Constant Small Water Removal Almost Always from Steam Drum Heat Recovery May be Desirable >Intermittent - Manual Dump to Clear System Heat Recovery Not Recommended 88

89 Boiler Codes 89

90 - Boiler Codes Important Code Levels >Low Pressure Boilers Vs High Pressure Boiler Low Pressure - Below 15 psig or Water at 250 F High Pressure are All Above These Critical Points >Codes Vary from State to State High Pressure Boilers Generally Require Around the Clock Operators Low Pressure Boilers Can be Operated Unattended >These are Space Conditioning Distinctions Pressure Codes Govern Relief Valve Settings 90

91 - Boiler Codes Low Pressure Applications >Low Pressure Boilers Used for Building Heating Systems Older Buildings with 15 psig (or less) Steam Newer Hydronically Heated Buildings on 180 F Water 91

92 - Boiler Codes High Pressure Applications >Hospitals Required for Sterilizer Operation >Central Heating Plants Higher Pressure Steam or High Pressure Hot Water to Optimize Long Pipe Runs >High Pressure Commercial Space Conditioning Systems Generally Limited to 125 psig or 400 F Hot Water (Pressurized) Requires Specialized Boilers 92

93 - Boiler Codes Very High Pressure >Occasionally Find Very High Pressure Systems (Steam Above 125 psig) Generally Never Leave Boiler House Used to Run Steam Turbine Equipment >Or Industrial Applications 93

94 Small Boilers 94

95 - Small Boilers Small Boilers >Steam (Older Buildings), Hot Water (Newer Buildings) >Up to 5 Million Btu/Hr. >Down to Residential >Variety of Designs Cast Iron Sectionals Packaged Units 95 Picture Courtesy of Weil McClain

96 - Small Boilers Cast Iron Sectional >Modern Solution to Heavy Cast-Iron Boiler Construction >Brought In Pre-Assembled or in Cross-Sectional Pieces >Fit Together with Gaskets >Heat Exchanger Bolted Together >Excellent for Very Difficult to Access Boiler Rooms in Existing Building 96 Picture Courtesy of Weil McClain

97 Copper-Fin Boilers - Small Boilers 97 Picture Courtesy of Lochinvar

98 - Small Boilers Ribbon Burners >Burner Ribbons >Gas and Air Inshot >Gas Line from Valve 98 Picture Courtesy of Weil McClain

99 - Small Boilers Controls > Traditional Safety Valve Arrangement > Electronic Ignition Now Universal > Dual Speed Firing (High/Low) Available 99 Picture Courtesy of Weil McClain

100 - Small Boilers Modular Systems > Larger Systems Constructed of a Number of Small Boilers on One Steam or Hot Water System > Efficiency Advantage at Low Loads One Boiler May Carry a Larger Building Through Fall/Spring Seasons More Continuous Operation 100 Picture Courtesy of Weil McClain

101 - Small Boilers Modular Systems > Access Solution - Easier to Get Multiple Boilers into Difficult to Access Existing Boiler Rooms 101 Picture Courtesy of Weil McClain

102 - Small Boilers Modular Systems 102 Picture Courtesy of UIC-ERC and Weil McClain

103 - Small Boilers Heating Delivery Options >Baseboard Radiation >Fan Coils >In-Floor Radiant Heating >Overhead Air 103 Picture Courtesy of UIC-ERC and Robur

104 Small Condensing Boilers 104 Picture Courtesy of Lochinvar

105 Condensing Operation Coming to Larger Boilers 105 Picture Courtesy of Viessmann Vertomat Condensing Boiler

106 Hydronic Accessories 106

107 Typical Installation 107

108 Expansion Tanks Diaphragm Type >As Water System Warms Up Water Expands into Tank Bladder Compressing Air Volume 108 Picture Courtesy of Amtrol

109 Expansion Tank 109 Picture Courtesy of State Industries

110 Air Separation and Venting >During Filling of a Hydronic System Air Will be Trapped >May Occur During Maintenance as Well >All Water Sources will Also have Dissolved Air >Need to Continuously Remove Any Air In System >Air in the System Will: Interfere with Proper Operation Oxygen Promotes Corrosion 110

111 Air Separation and Venting Tangential Tank Type 111 Picture Courtesy of Armstrong

112 Air Separation and Venting Separation Fitting Type 112 Picture Courtesy of Watts

113 Air Separation and Venting Separation Fitting Type Air Separator Constantly Removes Any Air 113 Picture Courtesy of Watts

114 2. Boiler Tuning

115 Learning Objectives >Determine the actual efficiency of existing boilers a key measurement in facility energy auditing >Diagnosing boiler problems, a valuable technique to handle customer high usage complaints and add to the customer relationship >Understand how the efficiency existing boilers may be improved without replacement or major expenditure 115

116 Overview >Flue Gas Analysis >Flue Gas (Combustion) efficiency charts >Efficiency and saving calculations >How is a burner retuning actually done? 116

117 Is Boiler Analysis Important? >The boiler may be the MAIN user of gas in the facility >Supplies space and water heating 117 Picture Courtesy GTI

118 The Burner is Where It Happens >The burner is where all the gas is combusted >If it is misadjusted all the energy flows in the facility are affected 118 Picture Courtesy GTI

119 Flue Gas Analysis 119

120 Flue Gas Analysis >Used to check combustion efficiency >Used to tune burner >Not an emissions test >Measure O 2,CO, CO 2 in exhaust >Measure exhaust temperature 120 Picture Courtesy GTI

121 Flue Gas 121 Picture Courtesy of Durovent

122 Flue Gas Analysis BUT >If too little air is available: >Gas will not burn completely >Will generate toxic carbon monoxide 122 Picture Courtesy of Bacharach

123 Flue Gas Analysis >If too much air is available: >Gas will burn completely >BUT extra air will carry away heat up the vent >Wasting energy 123 Picture Courtesy of Underwriters Laboratories

124 Flue Gas Analysis >Used to check the combustion air quantity >Exactly the right amount means there is no excess air >Called tuning burner 124 Picture Courtesy of Bacharach

125 What are we Tuning or Adjusting? >The amount of excess air Combustion requires a certain amount of air Any excess carried heat away up the flue The most efficient operation would be no excess air at all (0% excess air) But this would pose safety problems 125

126 What Does it Mean? >CO present in exhaust gas >Incomplete combustion indicated Need to admit more air 126 Picture Courtesy of W. Ryan

127 What Does it Mean? >No CO in exhaust gas >CO 2 below 10% Too much secondary air 127 Picture Courtesy of W. Ryan

128 Flue Gas Analysis What Does it Mean? >Heating up a lot of air and venting it Need to reduce air 128 Picture Courtesy of W. Ryan

129 How Can You Measure This? > This used to be a complicated > Involved liquid chemicals > Performed only for large boilers by experts 129 Picture Courtesy of Bacharach

130 Much Different Today >Electronics does all the hard work >Electronic measurement >Electronic results calculation 130 Picture Courtesy of Bacharach

131 Much Different Today >Electronic results calculation 131 Picture Courtesy of Bacharach

132 How is Measurement Done? >Insert probe into exhaust gases (as near to the boiler exit as possible) >Run a measurement 132 Picture Courtesy of Bacharach

133 How Can You Measure This? 133 Picture Courtesy of the Natural Gas Handbook

134 How is Measurement Done? Does Require Climbing to the Stack 134 Picture Courtesy GTI

135 Combustion Efficiency Calculation >When gas is burned >Heat from combustion: Is utilized for some process OR Goes up the stack in flue gases In Combustion Efficiency calculations - jacket losses are ignored 135 Picture Courtesy of Lochinvar

136 Combustion Efficiency >Combustion Efficiency is the percentage of the fuel s heating value that does NOT go up the vent >Remember this ignores jacket losses 136

137 Flue Gas Efficiency Charts 137

138 Combustion Efficiency Chart What is measured? >How HOT is the flue gas Hotter the flue gas, the more heat carried away The less heat available for the process >How MUCH flue gas is being produced Greater volume of flue gas, the more heat carried away up the vent The less heat available for the process >Charts: transmission grade natural gas ONLY 138

139 How the Chart Works >Line shown is for 400 F flue gas Excess air is air in excess of what is needed for complete combustion 139 Picture Courtesy of W. Ryan

140 How the Chart Works >Line shown is for 400 F flue gas If combustion is done with NO excess air The maximum possible heat is available 140 Picture Courtesy of W. Ryan

141 How the Chart Works >400 F flue gas If combustion is done with NO excess air the maximum possible heat is available Up to 82% of the Fuel Input 141 Picture Courtesy of W. Ryan

142 How the Chart Works The hotter the flue gas > The more energy lost up the flue > The LESS available heat for the process Efficiency declines as temperature increases 142 Picture Courtesy of W. Ryan

143 How the Chart Works The more excess air in the flue gas > The greater the flue gas flow The more energy lost up the flue > The LESS available heat for the process Flue gas efficiency declines as excess air increases 143 Picture Courtesy of W. Ryan

144 >Both charts are based on % excess air >Why not put them together 144 Picture Courtesy of W. Ryan

145 How is This Used? >Example >Existing older boiler Uses 100,000 MMBtu of gas per year at $6.00/MMBtu >Flue gas measurement 12% O 2 No CO 145

146 How is This Used? > Flue gas temperature 400 F 146

147 How is This Used? >Result: 125% excess air Combustion Efficiency =75% 147

148 Example >Readjust burner to 20% excess air Leaves margin to guard against dangerous incomplete combustion NEVER try for 0% excess air 148

149 Example >Readjust burner to 20% excess air Chart shows - adjust burner until O 2 in exhaust is at ~4% 149

150 Example >Readjust burner to 20% excess air If exhaust stays at 400 F New Combustion Efficiency =81% 150

151 Savings >Before tuning: Boiler burned 100,000 = $600,000/yr Heat available/yr: 100,000 MMBtu/yr x 75% =75,000 MMBtu/yr needed by the steam load >After tuning (same load) 75,000 MMBtu / 81% = 92,592 = $555,555/yr >Savings $44,444/yr just by retuning!!!! 151

152 Reference Note >Efficiency Numbers in Charts are Based on Available Heat Calculator Developed by the CEC by A Thekdi >Now Available on the DOE-EERE Site >Dry Basis - Does Not Handle Condensation 1 Company name ABC Corporation 2 Plant name or designation LA Plant 3 Plant address Main Street, Gabriel, CA Contact name Bob Smith 5 Contact address First Street, North Warren, CA Contact phone number and Phone: Date (format mm/date/year) May 12, Gas composition By volume Adjusted by volume 11 CH % % 12 C 2H % 1.500% 13 N 2 and other inert 2.00% 2.000% 14 H % 0.000% 15 C 3H % 0.500% 16 C 4H 10 + C nh 2n 0.00% 0.000% 17 H 2O 0.00% 0.000% 18 CO 0.00% 0.000% 19 CO % 0.000% 20 SO % 0.000% 21 O % 0.000% 22 Total of fuel components % % 23 Difference 0.00% 0.00% 24 Combustion air temperature ( F) % Oxygen (O 2) in COMBUSTION AIR % Oxygen (O 2) in flue gases 0 27 Calculated percentage excess air used Exhaust (flue) gas temperature ( F) Available Heat: (% of higher heating value of fuel) 79.24% Comment Note: The fuel gas composition is in volume %. The higher hydrocarbons in fuel are treated as same as C 4H 10 and all other inert gases are treated as N 2. Disclaimer: The California Energy Commission (Energy Commission), its contractor, Southern California Gas Company, and its subcontractor, E3M Inc., have made reasonable efforts to ensure that all information in this publication is correct. Neither the Energy Commission, Southern California Gas Company, nor E3M Inc. shall be responsible for errors or omissions in this publication or for claims or damages relating to its use. No publications or verbal representations of the Energy Commission, Southern California Gas Company, or E3M Inc. constitute any statement, recommendation, endorsement, approval, or guaranty (either express or implied) of any product or service. Developed by: Arvind Thekdi, E3M Inc. Click here for detailed Results Calculate Available Heat Heating equipment description (where the energy saving measure is applied) Equipment type (e.g. furnace, oven, kiln, heater, boiler) Equipment use (e.g., textile drying, aluminum melting) 10 Other comments if any The furnace was rebuilt recently. Fuel Gas Analysis (See note below) Furnace Metal heating b.smith@abccorp.com 152

153 Reference Note >Manual: ys/description/calculate%20available%20heat.pdf >Program: ys/calculatorlist.php >Hit: Calculate available heat Row and Download Software >Remember Non-Condensing Systems Only 153

154 Non-Condensing Chart 154

155 New - Full Chart 155

156 Other Useful Issues >What else is flue gas measurement good for? Significant presence of CO indicates dangerously insufficient air High flue gas temperature (even after tuning) indicated dilapidated boiler Chart will indicate actual operating efficiency of the existing old boiler - allow calculation of savings possible with boiler replacement 156

157 3. Boilers Retuning and Controls

158 Burner Retuning >Should be done by a bonded professional only >Poorly retuned burner can be dangerous 158

159 Burner Retuning Boiler burner air control mechanical pin type Each notch is a burner power level (20%,30%, etc.) Pin rack controls fuel and air flow at each power setting 159 Picture Courtesy GTI

160 Burner Retuning Lever Controlling Gas Flow Lever Controlling Air Flow 160 Picture Courtesy GTI

161 Burner Retuning Controller Motor Lever Controlling Air Flow 161 Picture Courtesy GTI

162 Flue Gas / Burner Control >Newer Burners Electronic burner controls variable speed blowers Using electronics to control gas flow Eliminates old mechanical systems with elaborate linkages set by installer Retuning is still required to re-calibration the air flow preset points 162

163 What s New? Electronics Replace the Mechanical Racks Variable Speed Blower Motor Electronically Controlled Gas Valve Still needs technician to set up and later retune air fuel mix at each power level 163 Picture Courtesy Baltur Burners

164 What s New? Electronics Replace the Mechanical Racks 164 Picture Courtesy of LAMTEC

165 Flue Gas / Burner Control >Latest Technology Continuous flue gas monitoring The Flue Gas Analyzer is permanently mounted on the boiler Excess air is constantly measured Continuous burner adjustment on flue gas data 165

166 What s Even Newer? Continuous Flue Gas Monitoring- O 2 Trim Control Permanently Mounted Excess Air Monitor Control Microprocessor Continuously Retuned Burner With Variable Speed Air Blower 166 Picture Courtesy of LAMTEC

167 Actual Integrated Controls Often Includes Oxygen Trim Control 167 Picture Courtesy of Hurst Boiler

168 4. High Eff. Small Boilers

169 Learning Objective >Understand new options for improving the efficiency of large scale industrial steam and commercial space heating hot water boilers 169

170 Overview >Smaller condensing boilers >High efficiency systems for large boilers >Heat recovery heat exchanger 170

171 Smaller Condensing Boilers 171

172 Smaller Boilers >Smaller / commercial boilers >Used for hot water and low pressure steam generation >Commercial building space heating service > MMBH in size 172

173 Smaller Condensing Boilers >Generation 1 condensing boilers Boilers with added heat exchangers >Generation 2 condensing boilers Boilers with air heaters 173

174 Generation 1 Condensing Boilers Generation 1 Condensing Boiler Conventional Boiler 174 Picture Courtesy of Atlantic Boiler

175 Generation 1 Condensing Boilers >Condensing boilers add another separate heat exchanger to lower exhaust gases further in temperature >Heating water runs thru condensing heat exchanger and then thru boiler 175 Picture Courtesy of Atlantic Boiler

176 Generation 1 Condensing Boilers >Added heat exchanger is where ALL the condensing take place >Added heat exchanger is composed of a material that resists corrosion from condensate 176 Picture Courtesy of Atlantic Boiler

177 Generation 1 Condensing Boilers >The lower the exhaust temperature the higher the efficiency >Gen 1 condensing boilers CANNOT lower exhaust temperature below the return water temperature of the heating system >The best application is any system with low return water temperatures 177

178 - Small Boilers New High Efficiency Hot Water Boilers >Internal layout Compact primary heat exchanger Secondary condensing heat exchanger Corrosion resistant stainless Up to 97% efficient Direct venting 178 Picture Courtesy of Lochinvar

179 - Small Boilers New High Efficiency Hot Water Boilers 179 Picture Courtesy of Cleaver Brooks Boiler

180 - Small Boilers Larger Condensing Boilers (to 4 MMBH) 180 Picture Courtesy of Fulton Boiler

181 Large Condensing Boiler Battery 181 Picture Courtesy of Fulton Boiler

182 Return Water Temp Dependency 182 Picture Courtesy of Fulton Boiler

183 Heating System Return Water Temperatures System Supply Water Temperature at Design Heating Load ( F) Return Water Temperature at Design Heating Load ( F) Radiator System Baseboard Radiation In-Floor Heating Fan Coils Supply and return water temperatures are often set down in warmer weather when much lower than design heating loads occur. Temperatures shown are approximate 183

184 Heating System Return Water Temperatures >Unless you can get exhaust down to <50 C (112 F), efficiency <90% >If the return water temp >~110 F, this can t happen 184 Picture Courtesy of Atlantic Boiler

185 Smaller Condensing Boilers >With higher temperature radiant or baseboard systems Temperature setback is needed to achieve efficiency promised in moderate weather Turns down water temps in mild weather Little or no condensing will occur during design (coldest weather) heating operation Result to the gas utility - doesn t reduce peak gas demand 185

186 Smaller Condensing Boilers >With lower temperature radiant floor systems Low return water temperature at all times More continuous condensing operation >WILL reduce peak gas load 186

187 Generation 2 Condensing Boilers Generation 2 Condensing Boiler Generation 1 Condensing Boiler 187 Picture Courtesy of Atlantic Boiler

188 Generation 2 Condensing Boilers >In this case, the condensing heat exchanger does NOT heat water >Condensing heat exchanger preheats combustion air >That heat recycles into the boiler 188

189 Generation 2 Condensing Boilers >With indoor combustion air air will remain in F range Constant consistent condensing >With outdoor combustion air Drops at design conditions Enhanced condensing in cold weather >Provides maximum efficiency in the coldest weather >WILL reduce peak gas load 189

190 Generation 2 Condensing Boilers >Condensing heat exchanger does NOT heat water >Condensing heat exchanger preheats combustion air 190

191 Generation 2 Condensing Boilers >With indoor combustion air air will remain in F range Constant consistent condensing >With outdoor combustion air Drops at design conditions Enhanced condensing in cold weather >Provides maximum efficiency in the coldest weather >WILL reduce peak gas load 191

192 Efficiency Comparison 192 Picture Courtesy of Atlantic Boiler

193 Boilers are Scalable to Commercial 193 Picture Courtesy of Atlantic Boiler

194 Relationship to Heating System >The return temperature of the heating system water only affects the exhaust temperature at the exhaust of water heat exchanger >Air preheater is not affected 194 Picture Courtesy of Atlantic Boiler

195 Venting 195 Picture Courtesy of Atlantic Boiler

196 Required Service Capacity Boiler Design Temp Heating Operation Maximum Output Maximum Gas Input Standard 80% 1.0 MMBH 1.25 MMBH Condensing low temp heating system 95% Low temp in floor heating 1.0 MMBH 1.05 MMBH Condensing 82% Baseboards 1.0 MMBH 1.21 MMBH 2nd Gen Condensing 98% Baseboards 1.0 MMBH 1.02 MMBH In evaluating the required gas supply capacity the efficiency at design (coldest) temperature is the only important point. Efficiencies shown are approximate. 196