Track: Commercial Natural Gas I Unit #4: Commercial Water Heating An overview of Water Heating Technologies Mr. Eric Burgis, Energy Solutions Center Copyright 2016 Energy Energy Solutions Solutions Center Center Inc. All Inc. All Rights Rights Reserved Reserved 1 Presentation Outline Market Overview Tank Style Water Heaters Tankless Water Heaters Booster Water Heaters Direct Contact Water Heater Small Boilers Heat Pump Water Heaters Commercial Opportunities 2 Market Overview 3 1
Commercial Buildings Water Heating Fuel Type Used COMMERCIAL WATER HEATING ENERGY SOURCES More than 80% of the 5.5M Commercial Buildings in the U.S. have some type of water heating capability. Natural Gas 38% Conversion Opportunities Electric 57% Propane 3% District heat Oil 0.5% 2% EIA, CBECS, Table B13. Selected principal building activity, revised May 2016 4 System Use Centralized Water Heating System: A type of water heating equipment that heats and stores water (for purposes other than space heating) in tanks and then distributes this heated water throughout the building. A residential type tank water heater is an example of a centralized water heater. Distributed Water Heating System: A type of system for heating water (for purposes other than space heating) that heats water as needed for immediate use near the location where this water is used. It is often called a point of use water heating system, and is usually located in more than one place within a building. Because water is not heated until it is required, this equipment is more energy efficient. 3500 3000 2500 2000 1500 1000 500 0 Water Heating Equipment (# buildings in 1,000 s) Centralized System Distributed Systems Combination of Centralized and Distributed Systems EIA, CBECS, Table B13. Selected principal building activity, revised May 2016 5 Natural Gas Consumption for Water Heating by Business Activity Warehouse and storage 2% Public assembly 1% Service 5% Other 1% Food sales 1% Education 13% Public order and safety 4% Lodging 27% Mercantile 14% Office 7% Food service 10% Health care 15% Source: EIA CBECS Table 7, Release date 3/18/16 6 2
Tankless Growth Rates In 2009 tankless represented 7% of the market In 2018 it is expected to be 9% of the water heating market for North America A large % of tankless are electric Source: BRG Study March 2014 7 Commercial Water Heating Types of Water Heaters Tank Style Tankless Booster Water Heaters Direct Contact Boilers Gas Heat Pump Water Heater Applications 8 Commercial Water Heater Efficiency Minimum efficiency standards for Commercial Water Heaters (> 199,000 Btu/hr) Commercial Type Title 10 Code of Federal Regulations, Part 431 Oct 29, 2003 Electric Storage Thermal Efficiency NA Gas fired Storage Thermal Efficiency 0.80 Oil fired Storage Thermal Efficiency 0.78 Gas fired Instantaneous Thermal Efficiency 0.80 Packaged Boiler 2.5+ MMBtu/Hr Thermal Efficiency 0.82 Units <= 199,000 BTU/Hr are typically use Energy Factor, while larger inputs use Thermal Efficiency. 9 3
Future Water Heater Efficiency U.S. 2015 Standards (Residential): GAS Common Sizes <= 55 Gallons > 55 Gallons Calculation EF = 0.675 (0.0015 x V) DF = 0.8012 (0.00078 x V) Rated Storage Volume Current Standard 2015 Standard Tankless 30 40 50 60 65 75.62.61.59.58.56.55.53.82.63.62.60.75.75.74 2015 DOE (Department of Energy) Final Rule Effective April 16th, 2015 Applies to residential water heaters, but these are used in small commercial applications as well. 10 Water Heating Technologies 11 Commercial Water Heaters Tank Water Heater Tankless Water Heaters Booster Water Heaters Direct Contact Water Heaters Boilers Heat Pump Water Heater 12 4
Tank Style Water Heaters Most common Least expensive Flexible 13 Tank Style Water Heater Hot water outlet Pressure / temperature relief valve Thermostat and gas valve Vent pipe Cold water inlet Flue tube / heat exchanger Flue baffle Anode rod Insulation Gas burner Combustion air openings 14 Tank Water Heater Offerings Atmospheric Direct Vent Power Vent 15 5
Tank Style Water Heater Sizing Commercial 35 gallons up to 300 gallons (132 1,135 liters) Efficiency DOE minimum standard: 67% residential, 80% commercial (apply derate of residential efficiency based on storage volume) Best available technology: 98% residential, 99% commercial Considerations Standby loss & Recovery Rate First hour rating 16 High Efficiency Storage Water Heater 399,000 2,000,000 BTU Input 125, 250, and 300 (473, 946, and 1,135 liters) Gallon Tanks Up To 99% Efficiency (low fire) Full Modulation with 10:1 Turndown Programmable Electronic Control with Digital Temperature Control Category IV Venting with CPVC Vent Material 10 Year Tank Warranty 3 Year Scale Warranty 17 Intelligence for Tank Water Heaters Microprocessor controls Tank maintain consistent temperatures Integrated mixing devices Allows for storage of hotter water increasing amount of usable hot water available Set back controllers Similar to programmable thermostat Leak detection devices Shuts off water if tank leak is detected Atmospheric flue dampers Reduces standby losses 18 6
Microprocessor Controls Advanced Temperature Controls Microprocessor constantly monitors and controls burner operation to maintain consistent and accurate water temperature levels Intelligent Diagnostics Provides diagnostic codes to assist in troubleshooting CONTINUED 19 Microprocessor Controls Self powered Thermopile converts heat energy from the pilot flame into electrical energy to operate the gas valve and electronics Retrofit replacement Service kits are available for direct replacement on certain units 20 Integrated Mixing Device Allows water in the tank to be stored at higher temperatures Increases usable hot water by as much as 50%, while controlling the hot outlet at a lower temperature CONTINUED 21 7
Integrated Mixing Device Mixed Hot Water Outlet Stainless Steel Flexible Connector ½ NPT Un Mixed Hot Water Outlet ½ NPT Recirculation Inlet Push to Turn Hand Wheel ¼ NPT Cold Water Outlet Cold Water Inlet *ASSE and UPC (IAPMO) Certified 22 Set Back Controller Similar user interface as heating/air conditioning thermostats 7 day/4 period programmable display Battery backup in case of power failure Can be remotely wired Hot water capacity indicator; provides an estimate of available hot water in the tank Energy savings of between 7% to 36% 23 Set Back Controller 24 8
Leak Detection Electronic sensor designed to detect leaks Triggers an alarm to alert business when a water heater leak is detected Installs in water heater drain pan Components are re usable can be removed and installed on a new water heater CONTINUED 25 Leak Detection Inlet Shut Off Valve Mounts on water heater inlet Shuts off the inlet water after a leak is detected and confirmed Requires electrical power to actuate valve Easily installed with provided bushings 26 Atmospheric Flue Damper Reduces stand by loss resulting in less gas consumption and higher EF Ratings Damper blade opens and closes automatically during operation and stand by mode Requires power to control damper 27 9
Commercial Fire Tube Condensing Removable dual heat exchangers Four passes of combustion gases through the water PVC venting Low NOx burners available Combustion Chamber 28 Tankless Water Heaters Standard Models Condensing Models 29 (Internal View) HOT WATER WATER OUTLET INLET Filter GAS How it Works Temperature is set via the controller Water tap opens & water begins to flow Turbine spins & sends signal to PC Board PCB determines water flow, firing rate & temperature Combustion fan motor starts Burner is ignited by direct electronic ignition and unit fires then modulates to match input with hot water flow When hot water tap is turned off The unit returns to standby mode 30 10
What is a Delta T ( T)? The difference of the incoming ground water and the tankless water heater s set point temperature is known as Delta T ( T) Delta T determines the flow rate of the tankless water heater EXAMPLE: The Tankless temperature is set at = 120 Subtract the incoming temperature from the water heater s set temperature for T: 120 57 = 63 T 31 Understanding Flow Rate The tankless water heater s first priority is to provide the set point temperature to the user. Based on the T, the tankless product may regulate flow to ensure it can provide the selected temperature. If incoming water is 57 and requested temperature is 120, T is 63 and gpm flow rate is 5.1 gpm Colder Inlet Water 63 EXAMPLE (from previous page) Subtract the incoming ground water temperature from the water heater s set temp. for T 120 57 = 63 The maximum GPM flow rate for any given T can be found at the intersecting points along each model s specific flow curve 32 Tankless Water Heaters Sizing Up to 380,000 Btu/hr Efficiency DOE minimum standard: ~82% Best available technology: 98% Benefits Higher flow rates than electric Compact size Long life 20 years or more Easy to service and repair Gas Piping Requirements ¾ gas line 5.0 inches wc minimum (12.7 centemeters) 33 11
Typical Manifold Installation Options Remote Control 140 140 To Hot Water Supply Gas Supply Expansion Tank Cold Water Supply 34 Recirculation Pumps Controlled by an Aquastat, Timer and/or both Sized to maintain circulation loop temperature Sized to overcome pressure loss through water heater supply and return plumbing Hot Water Supply 140 Check Valve (Required) RECIRCULATION LOOP Pump Cold Water Supply LOADS Expansion Tank 35 Manifold Controller Typical Commercial Manifold with Direct Recirculation Heavy Duty Heaters 140 140 140 Remote Control Gas Supply To Hot Water Supply Return Circulation Line Pump Expansion Tank Cold Water Supply 36 12
Good applications for Tankless Water Heaters in the Commercial Market Tankless models fit in a variety of commercial applications such as: Restaurants Hotels Multi family housing Government buildings such as schools Car washes Coin laundries Gyms Others 37 Booster Water Heaters 38 Booster Water Heaters Designed to heat rinse water for better cleaning with fewer spots especially on glassware Heats hot water from 120 140 F (48.8 60 C) up to 180 F (82.2 C) water Improves cleaning and sanitizing of dishes Shortens drying time Less wear & tear on dishwashing equipment and dishware Eliminates need for chemical rinse aids Environmentally friendly 39 13
Low Temp Dishwashing Does not effectively remove food and soil, resulting in a dish that is not visibly clean and may need rewashing 140 F (60 C) water temperature does not melt fats or proteins such as lipstick If water hardness is over 6 7 grains, spotting of dishware occurs Chemical effect on metals & etching of glasses and china Longer drying times due to low rinse temperatures 40 Other Booster Water Heater Advantages High temperature cleans better, especially on lipstick and grease residues. Dishes flash dry with high temperature giving you quicker turnaround and less water on the floor. High temperature units reduce chemical, water and sewer usage. Labor reduction & increased production (Reduce rewashing dishes) Safety in the workplace (Less water on floor means less slip and fall injuries) 41 Direct Contact Water Heaters 42 14
City water pressure through an engineered nozzle creates a specific spray pattern Stainless steel rings promote 99% efficient heat transfer Cold water inlet Hot water outlet Market Opportunities Laundries Foodservice Facilities Not intended for installations where water is recirculated 43 Direct Contact Water Heaters City water pressure feeds cold water into avertical tower The cold water falls by gravity through an area filled with stainless steel packing rings The burner provides hot combustion gases to the vertical tower of the heater where the hot gases come into direct contact with the falling water Rings increase the available surface area inside the tower to transfer heat and also keeps the water broken into smaller droplets CONTINUED 44 Direct Contact Water Heaters Droplets have a smaller diameter, enabling them to take on heat with nearly 100% efficient heat transfer As the combustion gases rise through the unit they transfer heat to the water falling in the opposite direction and are cooled until they exit through the stack Exhaust gases are close to the same temperature as the temperature of the water spraying through the top nozzle and are at near 100% relative humidity CONTINUED 45 15
Direct Contact Water Heaters The heated water falls down into the reservoir or storage area at the bottom A distribution pump, will deliver the hot water, on demand or continuously at the needed discharge pressure and desired temperature 46 Direct Contact Heater Thermal Efficiency 100 90 Thermal Efficiency 80 70 60 50 Typically, direct contact water heaters have an exhaust temperature about 10 20 F ( 12 to 6.6 C) above the incoming water temperature 40 60 70 80 90 100 110 120 130 140 150 160 170 180 Deg. F 15.5 21.1 26.6 32.2 37.7 43.3 48.8 54.4 60.0 65.5 71.1 76.6 82.2 Deg. C Exhaust Gas Exit Temperature Quikwater presentation, June 2011 47 Large Commercial Use Savings Example Annual Gas Costs for For Water Heating Systems Based on 60 to Based 140 F (60 C); on to 250,000 140 F; 250,000 Gallons gallons/day (946,352 use Liters) / Day Use $350,000 $300,000 $236,503 $265,051 $303,683 $250,000 $200,000 $150,000 $100,000 $50,000 $0 Direct Contact Direct Steam Indirect Steam Quikwater presentation, June 2011 48 16
Boilers for Larger Hot Water Needs 49 Sectional Boilers Contains multiple cast sections Unit sizing up to 150 hp New Condensing Boilers available Efficiencies approaching 97% 50 Small Fire Tube Boilers The furnace/burner section is a single largediameter tube with many small diameter tubes connected to it The small diameter tubes are arranged above the burner section to provide a larger heating surface area to heat the water Burner and tubes are contained entirely within an outer boiler shell that contains the water being heated Sizes ranges from 100 to 1200 horsepower 51 17
Small Water Tube Boilers Water circulates inside tubes heated externally by the burner Fuel is burned inside the furnace, creating hot gas which passes over the water tubes, heating the water in the tubes Typically larger than Fire Tube boilers 52 Finned Tube Boilers Water passes through boiler tubes while combustion gases remain on the shell side passing over the boiler tube surfaces Unlike conventional water tube boilers, the tubes are fitted with fins that increase the area available to transfer heat to the water 53 Condensing Wall Mounted Boiler Ultra High Efficiency Condensing Technology up to 98% Thermal Efficient (95%+ AFUE) Stainless Steel Heat Exchanger Ultra Low NOx emissions SCAQMD approved Designed for low maintenance and easy serviceability Fully adjustable outdoor reset technology with the sensors available Domestic Hot Water has Priority over hot water used to provide space heat 54 18
Commercial Heat Pump Water Heater 55 Natural Gas Engine Driven Heat Pump Water Heater Heat is extracted from the environment A Natural Gas engine replaces the electric motor to drive the system compressor The Engine also produces waste heat that is recovered to supplement the heat supplied by the heat pump The Engine drives a small electrical generator to provide electricity for fan motors, pump and controls Efficiencies up to twice that of a gas fired boilers 56 Commercial Heat Pump Water Heater Ambient Outdoor Temperature: 75 F (23.8 C) Hot Water Delivery Temperature: 120 F (48.8 C) COP = 586,000 / 292,000 = 2.0 57 19
Gas Heat Pump Water Heater Specifications 400,000 600,000 BTU/Hour (4 6 Therms) Ford 2.3 L 4 Cylinder Engine (<50 bhp) Ultra Low Emissions Small 5 kw generator for parasitic load Next generation control system Internet Based Touch screen display Advanced communications (CAN) Efficient, low pressure, HFC 134a refrigerant Open drive reciprocating compressor Custom evaporator coil design Compact brazed plate condenser 58 Electric Heat Pump Water Heater Fan Hot water outlet Pressure / temperature relief valve Upper Thermostat Resistance Elements Lower Thermostat Cold water inlet Drain Compressor Evaporator Anode rod Insulation Condenser 59 Electric Heat Pump Water Heating Systems Requires installation in locations that remain in the 40 90 F (4.4 32.2 C) range year round Install them in a space with excess heat such as a furnace room Generally cost 2X that of a Gas tank water heater ($1660 versus $850 for gas unit installed) Only save about $30/Year over a gas tank unit, or about 50% over electric tank unit 60 20
Gas Heat Pump Water Heater 1.6 Average Cycle COP EF: 1.3 First Hour: 60 80 gallons Heating Output: 10,000 ±Btu/hr(3 kw) Emissions: SCAQMD Compliant GHPWH Simple Savings Consumer Installation Installed Payback Market $/yr Cost Cost Cost [yrs] Size Capacity EF $/yr 50 gal 2.00 $271 $129 $1,100 $600 $1,700 6.2 Electric Heat Pump Electric Resistance 50 gal 0.95 $570 $428 $375 $400 $775 4.0 Gas Heat Pump 65 gal 1.30 $142 $1,800 $700 $2,500 Base Case Condensing Gas Storage 50 gal 0.82 $225 $83 $1,600 $800 $2,400 1.2 Opportunity Condensing Gas Tankless 199 kbth 0.90 $205 $63 $1,200 $1,000 $2,200 4.76 700,000 Non Condensing Tankless 199 kbth 0.82 $225 $83 $900 $1,200 $2,100 4.8 Power Vent Gas Storage 50 gal 0.67 $276 $134 $1,000 $600 $1,600 6.7 Standard Gas Storage 50 gal 0.62 $298 $156 $550 $500 $1,050 9.3 4+ million * Data from June 2015 TMAF presentation 61 Gas vs Electric Water Heater Comparisons Tank Style Water Heaters First Hour Rating Recovery rate Water Heater Cost Comparisons Energy Installed Costs Life Cycle Costs Emissions 62 Gas vs. Electric Tank Water Heater Whirlpool 40 Gallon Gas,.67 EF First Hour Rating Gas 67 gallons Electric 50 gallons Gas unit provides 34% more hot water in the first hour. Whirlpool 40 Gallon Electric,.92 EF GPH Recovery at 90 Deg F = 40.5 GPH Recovery at 90 Deg F = 20.7 Gas unit recovers twice as fast as the electric unit once cold. Source: Lowes.com 63 21
Canadian EnerGuide System Canadian EnerGuide Labeling System Gas Label Electric Label 64 Life Cycle Cost Analysis 22 21 20 19 18 17 16 23 15 New System 24 14 1 2 3 Years 13 4 10 11 12 Tank Replacement 5 9 6 8 7 Water Heating System installed year 1 Annual Costs include: Capital Cost Energy Cost Tank replacement in year 12 for all tank models Assume 24 year Life for tankless model 65 Life Cycle Costing Life Cycle Costs Electric Tank Water Heater Gas Water Heater (Power Vent) Standard Gas Tankless Water Heater Condensing Gas Tankless Water Heater Installed Cost Yr 1 $750 $1,200 $1,800 $2,500 Tank Replacement Yr 12 $750 $1,200 $0 $0 Year 1 Operating Costs $574 $238 $195 $166 12 Year Life Cycle Cost $8,030 $4,056 $4,140 $4,492 24 Year Life Cycle Cost $16,983 $8,112 $6,480 $6,484 * Assumes that electric pricing increases 1% a year, and that gas prices will hold stable for the foreseeable future. The payback on the initial tankless investment alone does not do justice for this technology. Simple paybacks do not account for the longer lifespan of the tankless water heater or the comparison to larger gas tank models for larger usage 66 22
Benefits of Natural Gas Water Heating Uses less energy costing about ½ as much to operate versus electric Rapid recovery 3 times faster than electric tank units Style and sizes to fit most installations Tank style Tankless Never run out of hot water Long life 20 years or more with tankless 67 Commercial Opportunities Water Heater Applications 68 Ice Rink Zamboni Filler 15 GPM (56.7 LPM) at 165 F (73.8 C) to fill Zamboni storage tank at ½ 1 hour intervals Prior system was gas fired tanks lasting 1.5 2 years Monthly fuel savings realized by tankless is $3,000 69 23
Eat In Restaurant Application New Installation Multi temp system meeting all kitchen & public washroom requirements 70 70 Hotel Tankless Application Hotel tankless system Providing over 100 GPM (378.5 LPM) / 4,400 GPH (16,655.8 LPH) Retrofitted to old boiler room location 71 Residential Condo Application 33 Story 387 Unit Condominium 3 condensing boilers for domestic hot water and base load heating 3 Boilers for retail hot water 3 condensing boilers for domestic hot water in recreation facility 72 24
Elementary School LEED Building LEED building 75,000 ft 2 (6,967.7 m 2 ) facility Two A.O. Smith Cyclone XHE gas water heaters rated at 94% thermal efficiency 73 Fitness Center Conversion 10 tankless water heaters replaced (2) 2,000,000 BTU boilers and 1,800 gallons (6,813.7 liters) of storage This system runs 42 showers and 10 lavatories 74 Drive In Restaurant Installing tankless water heaters in all new construction restaurants Restaurant 75 25
Thank you 76 26