Earth Energy & Ice

Earth Energy & IceEarth Energy & Ice

CNE.Sweet B/D 6th floor, 36-4, Geoyeo-dong, Songpa-gu, Seoul (Tel) 822-430-3728, 822-430-3729 (Fax) 822-430-2630 E-Mail : [email protected]

Port Hawkesbury Civic Centre, Port Hawkesbury, NSPort Hawkesbury Civic Centre, Port Hawkesbury, NS

• Project description• System description

• Conventional approach• Integrated geothermal approach

• Energy Use• Conventional system• Integrated geothermal system

• Environmental benefits• LEED™ certification benefits

• Other benefits

Port Hawkesbury Civic CenterPort Hawkesbury Civic Center

Port Hawkesbury Civic Centre, Port Hawkesbury, NS

Building includes: 1. 1,200 seat hockey arena, 48,900 square feet (4,545 m2)2. Town offices, 2,600 square feet (241 m2)3. YMCA fitness centre, 10,000 square feet (930 m2)4. Retail space, 5,200 square feet (483 m2)5. Conference centre, 19,200 square feet (1,785 m2)6. Theatre, 2,900 square feet (270 m2)7. Miscellaneous space, 3,300 square feet (307 m2)

SAERC Building Eligible for LEED SILVER CertificationEarth Energy system contributes

15 of 36 points

The BuildingThe Building

Main level Second level

Fitness10,000 sq. ft.

Offices2,600 sq. ft.

RetailTheatre2,900 sq. ft.

Change rooms

Conference

Ice rink

Concession

Fitness

Offices

TheatreRetailConference

Ice rink

Total building area: 92,100 sq. ft. (8,560 m2)

The BuildingThe Building

1,200 seat hockey rink

fitness centre

conference centre& town offices

Televised curling events

A Traditional Approach to an Ice ArenaA Traditional Approach to an Ice Arena

• Traditional approach made up of several independentindependent systems• Refrigeration plant to make ice• HVAC system• Dehumidification system in ice area• Service hot water for showers & resurfacing

Conventional Ice Rink System are Energy IntensiveConventional Ice Rink System are Energy Intensive

Electric heat

Gas boilers – space heat, pool heat & DHW

Arena heaters

Refrigeration

Gas heaters

Dehumidification

Hot water

Waste heat

Pool

Ice

Green house gases

Fossil FuelsFossil Fuels

1 unit of purchased fossil fuel

80-90% of heat to the building

10-20% of heat up the

chimney

C.O.P. = 0.9C.O.P. = 0.9

Electric HeatElectric Heat

1 unit of purchased electricity

1 unit of heat to the building

C.O.P. = 1.0C.O.P. = 1.0

Conventional Refrigeration Plant Conventional Refrigeration Plant

Refrigeration plant in a conventional ice rink typically consists of 1-3 industrial compressors. In Canada over 60% of the ice rinks use R717 (ammonia) refrigerant

A typical system contains 800-1,200 pounds (360-550 kg) of refrigerant, usually in a single refrigerant circuit

Screw compressor

Reciprocating compressor

30-hp brine pump

Fluid flow rates range from 800-1,500 gpm (50-95 l/s) Typically a 20-40 hp brine pump is needed

Conventional Refrigeration Plant MaintenanceConventional Refrigeration Plant Maintenance

Manufacturers recommend overhaul every 8,000 hours for reciprocating compressor (estimated $5,000 - $8,000)

…every 25,000 hours for screw compressor (estimated $12,000 - $18,000)

Reciprocating compressor overhaul

Cooling Tower Cooling Tower

Cooling tower sized for complete heat of rejection from refrigeration plant.

Maintenance problems, especially in colder climates.

High water consumption

Conventional HVAC System Conventional HVAC System

Rooftop units commonly used to provide heating and air conditioning

Exhaust fans and makeup air units provide fresh air for the building

Gas fired infrared heaters supply heat to the spectator stands at low capital cost

Rooftop HVAC system

Gas infrared heaters

Conventional Ice Rink Piping Conventional Ice Rink Piping

PVC headers in a header trench with mechanical connections

Steel header buried in center of floor with mechanical connections

Curved steel header buried in end of rink with mechanical connections

U-bends buried in concrete with mechanical connections

Integrated Approach to the Ice ArenaIntegrated Approach to the Ice Arena

• Integrated system is a single system that:• Refrigerates ice• Conditions the spaces in the building• Dehumidifies the ice area• Provides service hot water for showers & resurfacing

A single system can simultaneously provide simultaneously provide chilled and hot waterchilled and hot water. One or the other is free.

An earth loop stores energy and facilitates the opportunities for simultaneous heating and cooling

Integrated Geothermal HVAC & RefrigerationIntegrated Geothermal HVAC & Refrigeration

Heat taken from ice is stored in

earth loop

Heat pumps heat water to heat pool,

space & DHW

Pool

Ice

Heat pumps heat, cool & dehumidify area

Heat pumps transfer heat to and from

building to earth loop

Earth Loop absorbs excess heat & stores

it till needed

Innovation in Design(Simultaneous heating / cooling)

ID Credit 1.2: 1 point1 point

Optimize Energy Efficiency(45-55% energy cost reduction)

EA Credit 1: 8 points8 points

Innovation in Design(Snow melt reduce condense temp)


CFC ReductionEA Prerequisite 1

Integrated GeoExchange System $114,000/yrIntegrated GeoExchange System $114,000/yrOther Nearby Buildings Can be Connected to Loop Other Nearby Buildings Can be Connected to Loop

Heat from ice warms the building, or stored in earth loop. Nearby buildings take advantage of

warm earth loop

PoolIce

Earth Loop absorbs excess heat & stores it till needed

Earth EnergyEarth Energy


Plus 2.5 units of free energy from the earth

3.5 units of heat to the building

C.O.P. = 3.5C.O.P. = 3.5

Integrated Heating, Cooling & RefrigerationIntegrated Heating, Cooling & Refrigeration

3 units of heat from

the ice

4 units of heat to the building

C.O.P. = 7.0C.O.P. = 7.0


Low Temperature Fluid-to-Fluid Heat PumpsLow Temperature Fluid-to-Fluid Heat Pumps

8 water-water heat pumps provide refrigeration to make ice.

Heat is rejected either directly into building via radiant floor heat system, or into horizontal earth loop.

Heat is also drawn from horizontal earth loop when ice temperature is satisfied and heat is required.

Total refrigeration capacity at ice making temperatures: 88 tons

Refrigerant: 12 pounds (5.5 kg) R404A per unit

CFC ReductionEA Prerequisite 1

Eliminate HCFC & Halon(R404A refrigerant – 36 kg)

EA Credit 4: 1 point1 point

Rink Pipe Headers in Mechanical RoomRink Pipe Headers in Mechanical Room

Fusion welded headers for rink surface and thermal storage buffer located in mechanical room enhances serviceability.

Compression fitting valves on each circuit simplifies installation of pipe as well as flushing and purging system.

Rink piping can conform to rink shape since header is located in mechanical room.

Radiant Heat Directly from Refrigeration PlantRadiant Heat Directly from Refrigeration Plant

Floor heat in change rooms & lobby

Heated spectator seats

Snow melt pit for snow taken from ice

when resurfacing

Domestic Hot Water & Flood WaterDomestic Hot Water & Flood Water

Make up water is preheated directly by refrigeration heat pumps using a double wall vented heat exchanger

2 electric hot water tanks (12 kW ea) boost final water temperature to >120°F (50°C)

4 hot water storage tanks (120 US gallons or 450 l)

Water-to-water heat pump produces 120°F (50°C) water for showers & resurfacing ice

Forced Air Heat Pumps Provide Heating & CoolingForced Air Heat Pumps Provide Heating & Cooling

Water-to-air heat pumps provide heating and air conditioning as required in lobby, offices, conference centre, fitness centre and theatre

Ground Loop Reduces Use of Cooling Tower Ground Loop Reduces Use of Cooling Tower

Ground loop eliminates need to operate cooling tower for much of the year, even when heat is not needed in facility.

Fluid coolers run dry much of the time to reduce water consumption. Heat from loop is rejected at night taking advantage of cooler temperatures

Water Use Reduction – 20%

WE Credit 3.1: 1 point1 point

Water Use Reduction – 30%

WE Credit 3.2: 1 point1 point

* Source: Massachusetts Water Resources Authority

http://www.mwra.state.ma.us/04water/html/bullet4.htm



System SchematicSystem Schematic

Ice surface

Buffer

Floor heat

Future connection to SAERC Building

Forced air heat pumps throughout building

Make up water preheat

Hot water preheat

Evaporative fluid cooler

4 pairs low-temperature water-to-water heat pumps

Horizontal earth loop

System Schematic – Ice Surface is Heat SourceSystem Schematic – Ice Surface is Heat Source

Ice surface

Buffer

Floor heat




Heat pump boosts water temperature




Ice surface is primary heat source. Control of ice temperature is critical

System Schematic – Buffer is Heat SourceSystem Schematic – Buffer is Heat Source

4 pairs low-temperature water-to-water heat pumpsBuffer is secondary heat

source. Buffer is chilled at off-peak hours for refrigeration next day

Ice surface

Buffer

Floor heat







System Schematic – Earth Loop is Heat SourceSystem Schematic – Earth Loop is Heat Source

4 pairs low-temperature water-to-water heat pumpsWhen ice temperature is

satisfied & buffer temp. is low, earth loop is heat source if needed

Ice surface

Buffer

Floor heat







System Schematic – Rest of Building is Heat SourceSystem Schematic – Rest of Building is Heat Source


Forced air heat pumps act independently to heat and cool parts of building as needed

Ice surface

Buffer

Floor heat







System Schematic – Floor Heat is Heat SinkSystem Schematic – Floor Heat is Heat Sink


Floor heat is primary heat sink when ice surface or buffer are being chilled. Earth loop is alternate heat source when needed.

Ice surface

Buffer

Floor heat







System Schematic – Building is Heat SinkSystem Schematic – Building is Heat Sink


Forced air heat pumps act independently to heat and cool parts of building as needed

Ice surface

Buffer

Floor heat







System Schematic – SHW is Heat SinkSystem Schematic – SHW is Heat Sink


SHW is preheated by refrigeration heat pumps and temperature is increased by water-water heat pump

Ice surface

Buffer

Floor heat







System Schematic – Earth Loop is Heat SinkSystem Schematic – Earth Loop is Heat Sink


Earth loop is secondary heat sink when building is satisfied

Ice surface

Buffer

Floor heat







System Schematic – Fluid Cooler is Heat SinkSystem Schematic – Fluid Cooler is Heat Sink


Evaporative fluid cooler is “back-up” heat sink when earth loop temperature increases

Ice surface

Buffer

Floor heat







System Schematic – Other Building is Heat SinkSystem Schematic – Other Building is Heat Sink


Adjacent SAERC Building provides additional useful heat sink when connected to system

Ice surface

Buffer

Floor heat







Site Plan With Horizontal LoopSite Plan With Horizontal Loop

Civic Centre & ice rink

SAERC Building

165’ (50 m)

500’ (150 m)

Future connection to pool mechanical room in SAERC building

Horizontal Loop Location Beneath Parking AreaHorizontal Loop Location Beneath Parking Area

SAERC Building

Civic Centre

Horizontal Earth Loop ExcavationHorizontal Earth Loop Excavation

SAERC Building

Horizontal Earth Loop – Leveling BaseHorizontal Earth Loop – Leveling Base

SAERC Building

Horizontal Earth Loop – Connection to BuildingHorizontal Earth Loop – Connection to Building

Loop “sleeve” into Civic Centre mechanical room

Weeping Tiles Under Horizontal Earth LoopWeeping Tiles Under Horizontal Earth Loop

Roof water drained through weeping tile to keep loopfield moist, increase loop capacity

Stormwater Management

SS Credit 6.1: 1 point1 point

Horizontal Earth Loop – Under Paved ParkingHorizontal Earth Loop – Under Paved Parking

SAERC Building

Loop Connection to BuildingLoop Connection to Building

80 1” (25mm) circuits of HDPE pipe enter sleeve into building below grade and connect to fusion welded HDPE header with compression fitting valves

Earth Loop BenefitsEarth Loop Benefits

• Provide short term & seasonal energy storage• Heat that can’t be used is stored in loop• Heat source for system when ice satisfied

• Reduces or eliminates use of evaporative fluid cooler• Lowers electrical demand and consumption• Reduces water consumption• Fluid cooler is used when outdoor air is cooler

Evaporative Fluid CoolerEvaporative Fluid Cooler

Evaporative fluid coolers prevent loop temperature from climbing too high during peak summer use from ice making and air conditioning load.

The Rink Floor – Primary Heat SourceThe Rink Floor – Primary Heat Source

The piping in the rink floor serves as the primary heat source for the heat pumps.

Eliminating header at end of ice surface eliminates frozen corners outside the rink boards

Thermal Storage Buffer – Secondary Heat SourceThermal Storage Buffer – Secondary Heat Source

Ice & thermal storage buffer are heat source for building and domestic hot water. Buffer provides additional refrigeration during peak and provides a heat source for heat pumps at night when ice is not being used.

Thermal storage buffer

Innovation in Design(Thermal storage buffer)


Thermal Storage Buffer PipingThermal Storage Buffer Piping

The “thermal storage buffer” is sub-cooled during off-peak hours. This provides a significant portion of the refrigeration required when the ice is heavily used. Heat taken from the “buffer” is used for space heating and producing hot water.

Thermal Storage Buffer BenefitsThermal Storage Buffer Benefits

• Stores up to several hundred ton-hours of refrigeration• Reduces peak refrigeration demand• Holds ice during power outage

• Mass maintains constant ice temperature

• Reduces pumping power (60-70%)• Reduces refrigeration load

• Simultaneous cooling & heating doubles system COP (chill buffer at off-peak times & transfer heat to building)

Energy Consumption ComparisonEnergy Consumption Comparison

*Source: Natural Resources Canada (average energy use of 40 typical hockey arenas)

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

3,500,000

4,000,000

4,500,000

Conventional Integrated Geothermal

kWh

/ e

kWh

Co

nsu

mp

tio

n

Compressors Pump Condenser Heating SHW Lights Misc

20%

85%85%

85%

85%

Monthly Energy Balance from Typical Ice RinkMonthly Energy Balance from Typical Ice Rink

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

180,000

200,000

Sep Oct Nov Dec Jan Feb Mar Apr May

kWh

eq

uiv

alen

t / y

ear

Heating & SHW Heat Rejected from Refrigeration


Excess heat

Heat rejected by refrigeration plant

Heat needed in building

Typical Rink Monthly Energy Use – Conv. vs GeoTypical Rink Monthly Energy Use – Conv. vs Geo

0

50,000

100,000

150,000

200,000

250,000

Nov Dec Jan Feb Mar Apr

Eq

uiv

alen

t kW

h

Conventional Geothermal


Monthly Energy Balance from Typical Ice RinkMonthly Energy Balance from Typical Ice Rink

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep

ekW

h E

ner

gy

Co

nsu

mp

tio

n

Electrical Propane ekWh


Energy consumption of typical hockey arena* compared to Port Hawkesbury Civic Centre

Propane used mainly for desiccant dehumidification

PHCC Building Compared to Typical Hockey ArenaPHCC Building Compared to Typical Hockey Arena

Port Hawkesbury Civic CentreIce arena: 48,900 sq. ftAssociated building: 43,200 sq. ft.

Total Building: 92,100 sq. ft.

Fitness10,000 sq. ft.

Offices2,600 sq. ft.

Retail5,200 sq. ft.

Theatre2,900 sq. ft.

Change rooms

Conference19,200 sq. ft

Ice rink

Typical Hockey ArenaIce arena: 25,200 sq. ftAssociated building: 10,050 sq. ft.

Total Building: 35,250 sq. ft.

Ice rink

Change rooms

Lobby/viewing area

Ice rink

Energy Consumption Comparison – First YearEnergy Consumption Comparison – First Year

Source: Natural Resources Canada (average energy use of 40 typical hockey arenas)

Fine Tuning the SystemFine Tuning the System

• After first year of operation the system is being fine tuned.• The temperature sensors in the floor heat

system was found to be off by ≈ 10°F (5.5°C)• By calibrating the temperature the fluid

temperature was dropped from 85°F (29.5°C) to 75°F (24°C)

• This increased both efficiency and capacity of the low-temperature water-water heat pumps

• The base refrigeration / floor heat load was met with 2 pairs of heat pumps instead of 3

The Effect of The Effect of ΔΔTT

Chilling Capacity > 7.7%Chilling Capacity > 7.7%

Heating Capacity > 3.2%Heating Capacity > 3.2%

Efficiency > 16.1%Efficiency > 16.1%

kW demand < 11.3%kW demand < 11.3%

Daily Average kWh Consumption Drops in Jan. ‘06Daily Average kWh Consumption Drops in Jan. ‘06

5,880

5,043

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

Daily Avg kWh Use - '05 Daily Avg kWh Use - Jan '06

Over 14% reduction in electricity use

Energy Consumption Comparison – After 1Energy Consumption Comparison – After 1stst Year Year

Source: Natural Resources Canada (average energy use of 40 typical hockey arenas)

Lesson LearnedLesson Learned

• Design & operation of integrated system is critical for efficient operation• Floor heat layout and circuiting must be

designed to operate at low temperature• Building / system operator must be trained to

understand the implications of changing system setpoints

Port Hawkesbury CC – GHG Emissions ReductionPort Hawkesbury CC – GHG Emissions Reduction

0

50

100

150

200

250

300

350

Old Hockey Rink New Civic Centre

kg C

O2 /

m2

73% reduction in GHG emissions

Installation Cost Comparison & PaybackInstallation Cost Comparison & Payback

Conventional

Refrigeration & HVACIntegrated

Geothermal System

Refrigeration heat pumps $290,000 $330,000

Rink floor $160,000 $185,000

Radiant floor heat $75,000 $65,000

Domestic hot water $25,000 $35,000

HVAC $260,000 $260,000

Electrical to building $150,000 $150,000

Earth loop --- $220,000

Controls $90,000 $90,000

TotalTotal $1,050,000$1,050,000 $1,335,000$1,335,000

Energy CostEnergy Cost $380,240$380,240 $191,090$191,090

Simple payback:Simple payback: ($1,335,000 - $1,050,000) / ($380,240 - $191,090) = 1.5 yrs1.5 yrs

Installation Cost Comparison & Payback - RevisedInstallation Cost Comparison & Payback - Revised

Conventional

Refrigeration & HVACIntegrated

Geothermal System

Refrigeration heat pumps $290,000 $330,000

Rink floor $160,000 $185,000

Radiant floor heat $75,000 $65,000

Domestic hot water $25,000 $35,000

HVAC $260,000 $260,000

Electrical to building $150,000 $150,000

Earth loop --- $220,000

Controls $90,000 $90,000

TotalTotal $1,050,000$1,050,000 $1,335,000$1,335,000

Energy CostEnergy Cost $380,240$380,240 $171,590$171,590

Simple payback:Simple payback: ($1,335,000 - $1,050,000) / ($380,240 - $171,590) = 1.4 yrs1.4 yrs

More Effective Use of Renewable Energy More Effective Use of Renewable Energy

Renewable Energy, 5%

EA Credit 2.1: 1 point1 point





Geothermal systems reduce building energy consumption by 40-60% compared to conventional HVAC systems.

Renewable energy produced on site becomes a greater percentage of energy used.

More Effective Use of Green PowerMore Effective Use of Green Power

Geothermal systems reduce building energy consumption by 40-60% compared to conventional HVAC systems.

Green power used in the building becomes a greater percentage of energy used.

Green Power

EA Credit 6: 1 point1 point

LEED Credits – Up to 23 Points Using Earth Energy!LEED Credits – Up to 23 Points Using Earth Energy!CreditCredit DescriptionDescription PointsPoints

SS: 5.2 Reduced site disturbance, footprint 11

SS: 6.1 Stormwater management 11

WE: 3.1 Water use reduction, 20% 11

WE: 3.2 Water use reduction, 30% 11

EA: Prerequisite 1 Minimum energy performance RequiredRequired

EA: Prerequisite 2 CFC reduction in HVAC&R Equip RequiredRequired

EA: 1 Optimize energy performance 1-101-10

EA: 2.1 Renewable energy, 5% 11



EA: 4 Elimination of HCFC’s & Halons 11

EA: 6 Green power 11

ID: 1.1 Innovation in design 11




Up to 23 pointsUp to 23 pointsCertified 26-32 points Silver 33-38 points Gold 39-51 points Platinum 52-69 points

Benefits of Integrated Geothermal SystemBenefits of Integrated Geothermal System

• Energy consumption reduced 40-60%• Elimination of fossil fuels• Reduced refrigeration charge• Reduced pumping horsepower• Reduced service and maintenance• Maintenance done by local technicians• System redundancy reduces service• Thermal storage buffer enhances ice

quality• System can be retrofit without buffer

Date post:	13-Jan-2016
Category:	Documents
Upload:	teo
View:	33 times
Download:	1 times

Earth Energy & Ice

Documents