Transcript Bradford White Solar Thermal Training Program

Bradford White Solar Thermal
Training Program
A Fundamental Review of Solar Thermal Systems
Installation, Sizing and Benefits of a Bradford
White Solar Thermal Water Heater
How Does Solar Thermal Work?
• The sun’s rays hits a solar collector, heating the fluid
inside.
• The heated fluid in the collector passes through a heat
exchanger, which transfers its heat energy to the
surrounding potable water.
• If an internal or external heat exchanger is not available,
the heated collector fluid goes directly into the potable
water in the tank.
Solar Fraction (SF)
– One way of expressing the thermal performance of a solar
system is by stating the percentage of the load met by solar
energy on a month-by-month basis.
– Monthly totals can be combined to yield the annual solar
fraction, expressed as a decimal percentage (e.g. 0.15 = 15%)
– If a solar system has a SF of 0 then there is no solar energy
utilized. If it has a SF of 1.0 then all energy provided is from
solar.
– Dependent on many factors such as load, collector size,
climate, etc.
– Example, the same solar equipment installed in a home in
Arizona may have a SF of 75%, but if installed in
Connecticut, it may only have a SF of 30%.
System Types
•
Active is when a circulator pushes the fluid.
•
Passive is when water temperature difference moves
the water. Hot water rises/cold water falls.
•
Open loop is when the potable water goes through the
collector to be heated.
•
Closed loop is when the heating fluid is closed off
from the potable water and is contained in a loop.
Open Loop System
Closed Loop System
Solar Rating
• The Solar Rating and Certification Corporation (SRCC) was
provides independent testing, rating and certification of active
solar collectors and solar domestic water heating systems.
• Standard OG-100 “Operating guidelines for certifying solar
collectors”
• Standard OG-300 “Operating guidelines and minimum
standards for certifying solar water heating systems”
OG-300 Certification
• Standard OG-300 combines the physical testing of collectors
and all major components in a solar water-heating system
proposed for sale by manufacturer.
•The standard also provides simulated performance estimates
for that system in specific geographical locations.
• Once a water heater is OG-300 certified, it then becomes
ENERGY STAR® certified.
Solar Thermal System Components
•
Storage Tank
– Stores and delivers heated potable water.
•
Collectors
– Flat Panel; more efficient in warmer climates
– Evacuated Tube; more efficient in colder climates
•
Circulation
– Circulators
•
Controls
– Thermistors
•
Fluid - the more glycol in the system, the harder the circulator works and
lower the heat transfer capability.
Heat Exchange Coil
•Vitraglas® lined, 1 ½” O.D. carbon steel coil.
•Single Wall provides greater heat transfer.
•Double Wall provides additional protection from heating
fluid and surrounding water.
•Because of the large diameter, a smaller and lower cost
pump can be installed.
•Smooth internal surface area limits the amount of mineral
deposit, which could decrease heat transfer capabilities.
•Glycol and toxicity rating of 1 (practically non-toxic) fluid
can be introduced into coil.
Heat Exchange Coil
• 1” NPT female fittings on single wall
• ¾” NPT female fitting on double wall
• The coil has a heat transfer area of 14.2 sq ft
• Stored water volume of 2.7 gallons
• Because of the material and thickness of the coil,
maximum supply temperature from a heating
source can be upwards of 240°F
•Maximum supply temperature from a heating
source must not exceed 250 F
Heat Exchange Coil
Double Wall
Single Wall
Double Wall Heat Exchange Coil
Head Loss
• Head
loss due to friction of water flowing in a pipe is determined in feet of
head. As water moves through pipe and fittings, it loses energy to friction.
Pumps or circulators provide the energy to make up for this loss “head loss”
through the system.
• The more water you push through the pipes, or the smaller the pipes are, the
higher the head loss will be.
• Higher head loss means larger more expensive pumps.
Sizing a Circulator
Heat Exchanger Pressure Drop
Heat Exchanger Pressure Drop Curve
7.00
16.00
Single-wall
14.00
Double-wall
12.00
5.00
10.00
4.00
8.00
3.00
6.00
2.00
4.00
1.00
2.00
0.00
0.00
0
1
2
3
4
5
6
7
8
Flowrate (GPM)
9
10
11
12
13
14
Total Head Loss(Feet)
Total Pressure Drop
(PSID)
6.00
Integrated Mixing Device Package
Integrated Mixing Device Features:
• Push to turn hand wheel prevents accidental temperature change.
• Included thermo-strip to approximate outlet water temperature.
• Allows water in the tank to be stored at higher temperatures, increasing usable hot water
by as much as 50%, while controlling the hot water outlet at lower temperatures.
• Additional outlet piping connection to draw off unmixed tank temperature water.
• Additional intlet piping connection for recirculation water into the mixing device.
• Additional outlet piping connection to draw off cold water without installing a saddle valve.
• Teflon® coated internal components to extend product life.
Integrated Mixing Device*
Stainless Steel
Flexible Connector
Mixed Hot Water
Outlet
Cold Water Inlet
½” NPT UnMixed Hot
Water Outlet
½” NPT Recirculation
Inlet
Push to Turn
Hand Wheel
¼” NPT Cold Water
Outlet
*ASSE and UPC (IAPMO) Certified
Push to Turn Hand Wheel
100°F to 145ºF
Temperature Range
Graduation marks to allow
easy adjustment. Each increment is 5ºF.
Arrow is approximately 120°F
Solar Saver®
Electric Backup (Open Loop)
Solar Saver® Models
• Models available
– No heat exchanger; potable water is circulated
through the solar collector. Suitable for frost free
locations.
• Single (upper) heating element
• Supplied thermistor wires
• Connections
– Potable -- Inlet dip tube; Anodic outlet device
– Solar – Dip tubes in top of water heater
• Alternate side connects in 80 & 120 gallon
models.
• Solar sensor can be mounted by means of threaded stud.
Solar Saver® Specification Data
Open Loop
Model Number
MS65R6SS
MS80R6SS
MS120R6SS
First Hour
US
Delivery Single
Gal
Elements
65
80
119
46 gl.
53 gl.
83 gl.
Floor to
Heater Top
59"
59"
62 1/2"
Jacket Shipping
Dia.
Weight
22"
24"
28"
168 lbs.
210 lbs.
310 lbs.
EcoStor™ Electric Backup
EcoStor™ Solar Indirect Models
• Models available
– Single Wall Heat Exchanger for increased
performance
– Double Wall Heat Exchanger for additional
protection between the heating fluid and potable
water.
• Single (upper) or Dual Incoloy elements
– 4.5 or 5.5 kW elements.
• Integrated Mixing Device for piping flexibility
• Supplied thermistor wires
• Two Anodes
EcoStor™ Specification Data
Single Wall Heat Exchanger
Model Number
First Hour
First Hour
US
Delivery Single Delivery Dual
Gal
Elements
Elements
S-SW2-60R6DS
60
S-SW2-75R6DS
75
S-SW2-115R6DS 115
46 gl.
53 gl.
83 gl.
84 gl.
97 gl.
124 gl.
Floor to
Heater Top
Jacket Shipping
Dia.
Weight
59 1/4"
59 1/4"
62 3/4"
22"
210 lbs.
24"
236 lbs.
28 1/4" 340 lbs.
EcoStor2™ Specification Data
Double Wall Heat Exchanger
Model Number
First Hour
First Hour
US
Delivery Single Delivery Dual
Gal
Elements
Elements
S-DW2-60R6DS
60
S-DW2-75R6DS
75
S-DW2-115R6DS 115
46 gl.
53 gl.
83 gl.
84 gl.
97 gl.
124 gl.
Floor to
Heater Top
Jacket Shipping
Dia.
Weight
59 1/4"
59 1/4"
62 3/4"
22"
217 lbs.
24"
241 lbs.
28 1/4" 345 lbs.
EcoStor™ Heat Exchanger Backup
Heat Exchanger Backup
• Models available
– Single Wall Upper Heat Exchanger
– Double Wall Lower Heat Exchanger
• Dual Heat Exchanger Design
– Can be connected to a variety of different heating
systems.
– Solar, space heating, geothermal heating, boiler
heating
• Integrated Mixing Device
• Supplied thermistor wires
• Two Anodes
Solar Thermal
EcoStor™ Specification Data
Dual Heat Exchanger
US
Gal
S-DC-DW2-55R6SW
55
S-DC-DW2-70R6SW
70
S-DC-DW2-110R6SW 110
Model Number
Floor to
Heater Top
62 3/4"
62 3/4"
66"
Jacket
Dia.
22"
24"
28 1/4"
Shipping
Weight
282 lbs.
313 lbs.
442 lbs.
Dual Heat Exchanger Connections
EcoStor2™ Gas Backup
Atmospheric Vent
EcoStor2™ Gas Backup
• Models Available
– Natural Gas or Propane Gas
– Atmospheric Vent
– Double Wall Heat Exchanger
– 61,000 – 76,000 BTU/hr. input range
• Honeywell Self Diagnostic Gas Control
– Advanced temperature control system
– Intelligent diagnostics
• Integrated Mixing Device
• Supplied thermistor wires
• Two Anodes
EcoStor2™ Specification Data
US
Gal
S-DW2-504T6FBN 45
S-DW2-65T6FBN
60
S-DW2-75S6BN
70
Model Number
Nat & LP
Floor to Vent Jacket
Shipping
Vent
BTU/hr Input
Conn.
Dia.
Weight
65,000/61,000
59 1/4"
22"
4"
223 lbs.
65,000/63,000
63"
24"
4"
264 lbs.
76,000/76,000
62 3/8"
26"
4"
306 lbs.
Propane models feature a Titanium Stainless Steel Propane Burner.
For propane (LP) models, change suffix “BN” to “SX”.
EcoStor2™ Gas Backup
Power Vent
EcoStor2™ Gas Backup
•
Models Available
– Natural Gas or Propane Gas
– Power Vent (3” or 4” PVC, CPVC, ABS)
– Double Wall Heat Exchanger
– 60,000 – 76,000 BTU/hr. input range
•
Honeywell Self Diagnostic Electronic Gas Control
– Advanced temperature control system
– Intelligent diagnostics
– Optional Programmable Setback Control
•
Integrated Mixing Device
•
Supplied thermistor wires
•
Two Anodes
EcoStor2™ Specification Data
US
Gal
S-DW2-TW-50T6FBN 45
S-DW2-TW-65T6FBN 60
S-DW2-TW-75S6BN 70
Model Number
Nat & LP
Floor to Vent Jacket
Vent
BTU/hr Input
Conn.
Dia.
67,000/60,000
59 1/4"
22" 3" or 4"
70,000/63,000
63"
24" 3" or 4"
76,000/75,500
62 3/8"
26" 3" or 4"
Propane models feature a Titanium Stainless Steel Propane Burner.
For propane (LP) models, change suffix “BN” to “SX”.
Shipping
Weight
247 lbs.
281 lbs.
336 lbs.
EcoStor2™ Gas Backup
Atmospheric Vent Ultra Low NOx
EcoStor2™ Gas Backup
•
•
•
•
•
Models Available
– Natural Gas Only
– Atmospheric Vent
– Double Wall Heat Exchanger
– 40,000 – 55,000 BTU/hr. input range
– Ultra Low NOx radiant burner
– Meets the most stringent air quality requirements for
allowable NOx emissions in the country
Honeywell Self Diagnostic Gas Control
– Advanced temperature control system
– Intelligent diagnostics
Integrated Mixing Device
Supplied thermistor wires
Two Anodes
EcoStor2™ Specification Data
US
Gal
S-DW4-U5036FRN 45
S-DW2-U65T6FRN 60
Model Number
Nat BTU/hr
Input
40,000
55,000
Floor to Vent Jacket
Shipping
Vent
Conn.
Dia.
Weight
59 1/4"
22"
3"
233 lbs.
63"
24"
4"
272 lbs.
How Do I Size a System?
Water Demand
•
Determine the Daily Hot Water Demand (Gal.)
– If unknown, estimate 30 gallons per person per day.
– Determine typical inlet water temperature (°F) and desired outlet temperature
(°F).
– Calculate the amount of Btu’s needed per day.
• BTU = Gallons x 8.25 x (Outlet – Inlet)
• Example: 4 people with 58°F inlet with a 125°F tank
• 4 people x 30 gallons/day = 120 gallons per day
• BTU = 120 x 8.25 x (125-58) = 66,330 Btu/day
How Do I Size a System?
Collector Demand
•
Flat panel – (Btu/day/1,000) x 1.1 = ft.2 of area.
– More efficient in warmer climate/summer.
•
Evacuated Tube – (Btu/day/1,000) x 1.3 = ft.2 of area.
– More efficient in cooler climate/winter.
– Collector temperature - outside temperature is larger.
•
Calculate the amount of collector surface area.
– Flat Panel: (66,330 Btu/day/1,000) x 1.1 = 73.0 ft2.
– Evacuated Tube: (66,330 Btu/day/1,000) x 1.3 = 86.2 ft2.
•
Other variables exist such as climate and panel location
Questions?