Other Names for Ground Loop - rockymtnashrae.com...Heat Recovery To OA AHU: 125 F Hot Water Water ‐to ... 3.412 (BTU/Whr) * W(watts) 4 x L(ft of loop) x Slope( F) Thermal Conductivity

Commercial Ground LoopWater Source Heat Pump Systems

Presented byAlan NilesCommercial Regional Sales ManagerWaterFurnace International

Other Names for Ground Loop Systems

GeothermalGround SourceGround CoupledGeoExchange

Why a Ground Loop Heat Pump System

Tax Incentives

Lower Operating Costs

Lower Life Cycle Costs

Lower Maintenance Costs


Tax Incentives

Lower Operating CostsNeed Building Loads and Ground Loop Design Software for Monthly Average Water Temperatures

Lower Life Cycle CostsNeed Ground Loop Installed Cost

Lower Maintenance Costs

Tax Credits: with no limit – until 1/1/2017

Energy Property Tax Credit: 10% of total system cost with no limit10% grant available in lieu of tax creditCombine with solar and wind tax credits

2010 IRS Form 3468 Investment Credit

Part III, LINE 12 r Energy credit: Geothermal heat pump systems

Basis of property placed in service during the tax year that was acquired after October 3, 2008, and the basis attributable to construction, reconstruction, or erection by the taxpayer after October 3, 2008 ..............$____________ × 10% (.10)

Federal Tax Incentives for Commercial GLHP Systems

Tax Deductions:

Energy Efficient Commercial Building Property Tax Deduction: ($1.80 per Sq Ft)Combine with other Qualified Section 179 Real Property Deductions

A software model of 3 installed components:1) the building envelop2) the indoor lighting3) the HVAC and hot water system

compared to the minimum ASHRAE 90.1‐2001 design. Combined, the 3 components must reduce energy by 50%. Or as individual parts, each component must reduce energy by 16.667%.

Tax Deduction:If all 3 components meetor exceed 50% Energy savings $1.80 per square foot of entire structure

If only the HVAC and Hot Water Systemmeets or exceed 16.667% Energy savings $ 0.60 per square foot of entire structure


Tax Deductions:

Energy Efficient Commercial Building Property Tax Deduction:

Energy savings must be calculated using a qualified computer software approved by the IRS.

Some approved software: DOE 2.2, E‐Quest, Energy Plus, Energy Pro, HAP, TRACE 700

Filing:This answer is copied from website: http://www.efficientbuildings.org/about_the_provision.html#01

There is no special form to claim the deduction. The IRS instructions to business forms (e.g., Form 1120 for corporations, Form 1120‐S for S corporations, and Form 1065 for partnerships) indicate that the taxpayer should include the amount of the deduction in the amount in the "Other deductions" line of the tax return. … it is important that a taxpayer obtain and retain the necessary certifications and documentation to claim the deduction (see, IRS Notice 2006‐52 for these requirements).


Tax Deductions:

Accelerated Depreciation:

1/1/2012 until 12/31/2012:50% first year bonus depreciation with the balance on a 5 year MACRS depreciation

2010 IRS Form 4562 Instructions

Part II Special Depreciation Allowance and Other DepreciationLine 14For qualified property placed in service during the tax year, you may be able to take an additional 50% special depreciation allowance.


Example:


New Construction: $2,000,000 to install geothermal heat pump system. Building occupied August 2012 (3rd quarter).

40% tax bracket when state income tax is included.

2012 Tax Credit: $2,000,000 x 10% Credit = $ 200,000Depreciable Basis: $2,000,000 ‐ ($200,000/2) = $1,900,0002012 Bonus Tax Benefit: $1,900,000 x 50% bonus x 40% tax rate = $ 380,0002012 MACRS Tax Benefit: $190,000 x 40% tax rate = $ 76,000Total Tax Benefit for 2012: = $ 656,000

2013 MACRS Tax Benefit: $304,000 x 40% tax rate = $ 121,6002014 MACRS Tax Benefit: $182,400 x 40% tax rate = $ 72,9602015 MACRS Tax Benefit: $109,440 x 40% tax rate = $ 43,7762016 MACRS Tax Benefit: $109,440 x 40% tax rate = $ 43,7762017 MACRS Tax Benefit: $54,720 x 40% tax rate = $ 21,888

Total Tax Savings: $960,000Plus Tax Deductions from theEnergy Efficient Commercial Building Property Tax Deduction

Eligibility:Building located in U.S.Original use begins with taxpayerBuilding design must fall under the guidelines of ASHRAE 90.1 Energy Standard for Buildings Except Low‐Rise Residential Buildings



Lower Operating Costs

Use the ground’s constant temperature as the sourceof heat in winter and as a high efficiency heat sink in summer

85 FSupplyWater

95 FReturn Water

10F Across the Cooling Tower

GLHP Operating Costs Basics

95 F

90 FReturn Water

79 F

85 FSupplyWater

95 F

87 F

Only 5F Across the Cooling Tower

One unit in each zone with individual local temperature control


95 F

86.8 FReturn Water

79 F

85 FSupplyWater

95 F

84 F

Only 1.8F Across the Cooling Tower

Heat Recovery To OA AHUSnow MeltDomestic Hot Water Pre‐Heat130 F or 160 F Hot Water

Water‐to‐Water Unit


95 F

86.8 FReturn Water

79 F

85 FSupplyWater

95 F

84 F


Boiler/Cooling Tower 20% to 25% of Total HVAC Operating Cost


95 F

86.8 FReturn Water

79 F

85 FSupplyWater

95 F

84 F

Heat Recovery To OA AHU:125 F Hot Water


Supply Water approaches Ground Temperature

Only 1.8F to the Ground Loop

Operating Cost Basics


Typical Water Source Heat Pump Cooling Performance


33% Increase


GLHP Basics


33% IncreaseIMPORTANTGround Loops approach ground temperature when the Building is not at Peak Loads

80% ‐ 90% of the time, building loads are at 50% or less of the Peak Load

Installation Costs

GLHP Design Basics

NEED TO KNOW:

From the Ground: Thermal Conductivity and Average Ground Temperature

From the Building: Monthly/Daily Loads

From the Equipment: GLHP Efficiency of Each Specific Heat Pump

GLHP Design Basics

The Ground

GLHP Design Basics

20 10 Tm 10 20

4

8

12

16

20

24

28

Dep

th in

Fee

t

WET SOIL(0.96 sq. ft./day) or

(0.40 sq. ft./hr)

AVERAGE SOIL(0.6 sq. ft./day) or(0.025 sq. ft./hr)

LIGHT DRY SOIL(0.26 sq. ft./day) or

(0.011 sq. ft./hr)

GLHP Design Basics

Thermal ThermalConductivity Diffusivity

Material (Btu/hr-ft-F) (ft2/day)

Dense Rock 2.00 1.2Average Rock 1.40 0.96Heavy Soil, saturated 1.40 0.84Heavy Soil, damp 0.75 0.60Heavy Soil, dry 0.50 0.48Light Soil, damp 0.50 0.48Light Soil, dry 0.20 0.26

GLHP Design Basics

Thermal Conductivity Test

Required Test Duration – A minimum test duration of 36 hours is recommended, with a preference toward 48 hours.

TC Test: $8,000 to $12,000

GLHP Design Basics






Drillers Need to Know to bid competitively



Thermal Conductivity (k) =

3.412 (BTU/Whr) * W(watts)4 x L(ft of loop) x Slope(F)


Ground Loop Site Layouts

Reverse Return Piping for Ground Loop

Each Bore hole has identical pressure dropSo no balancing valves required under ground

GLHP Design

Ground Loop Site Layout

Valve Vault

400 Foot Bore Hole Layout






Mechanical Room



Drilling Holes

&

Installing Pipe

Typical vertical bore detail

Vertical Loop Cross Section


Vertical Loop Pipe with U‐Bend


Vertical Loop Pipe with U‐Bend

PE 3408 HDPE (High Density Polyethylene Pipe)

1” IPS SDR‐111.25” IPS SDR‐112” IPS SDR‐113” IPS SDR‐15.54” IPS SDR‐15.56” IPS SDR‐15.5 8” IPS SDR‐15.5

Standard Dimension Ratio (SDR) is the Side Wall Thickness to the Pipe Diameter Ratio

GLHP Design


PE Pipe Cell Classification PE 355434C

PE: Polyethylene3: Density (0.941 ‐ 0.955 g/cm3)5: Melt Index (ASTM D‐1693, 10.1.4)

Molecular Weight5: Flexural Modulus4: Tensile Strength at Yield3: Environmental Stress Crack Resistance4: Hydrostatic Design Basis at 23CC: Color and UV Stabilizer

GLHP Design

Selecting Pipe Size for the Bore Hole

GLHP Design

Selecting Pipe Size for the Bore Hole

GLHP Design Design Goal: 15 Ft H2O pressure dropfor entire ground loop

Vertical bore without backfill

BentoniteGrout backfill

Geothermal pipe

Grout

Standard Bentonite Grout = 0.43 TC

Select Grout = 0.85 TC

Thermally Enhanced orThermal Select Grout = 1.0 to 1.4 TC

Adding silica sand increases the TC but also increases cost in both material and time

Grout

Grout

49 % Increase in Grout

600 Ton School Application - North Royalton, Ohio

North Royalton Middle School

Middle School, Ohio

Middle School, Ohio

• Built in 1996

• 1600 Students

• 239,000 square feet

• 140 units (average size 3 tons )

• 414 total tons

• 240 bore holes at 330 ft deep

Middle School, Ohio

• Mechanical HVAC System was installed for $ 10 per square ft

($ 2.4 million).

Ground Loop Portion Turn Key Cost: $ 500,000

$ 6.30 per foot of bore hole

• System projected to operate at 25 cents per square ft.

System actually operating at 18 cents per square ft.

Murray High School

New Public School built in 2006

Loop Field Layout

Construction Cost Comparison

1st Year Operating Cost Comparison

316 – 300’ boreholes Under North Parking Lot

High School Ground Loop Field

High School – Row of Vertical Loops

High School – Rows Connected

High School – Back Filling the Trenches

High School – Finished Ground Loop

MECHANICAL SYSTEM SAVINGS

• Conventional System Bid: $19.00 / sq ft

• Ground Source System Bid:

Mechanical/Plumbing bid: $3,065,161

Loop Field bid: $930,784

Total: $3,995,945

Mechanical Cost: $3,995,945 / 267,256 sq ft = $14.95 /sq ft

• Construction Cost Savings: 267,256 sq ft x $4.05 /sq ft = $1,082,387.00

• Total Bore Hole Length: 316 holes x 300 ft deep = 94,800 feet of bore hole

Ground Loop Installed cost: $930,784/94,800 = $9.20 per foot of bore hole

• Annual Geothermal System Utility Costs – Murray High School

Electricity = $156,505.11 (96%)

Natural Gas = $6,521.05 (4%)

Total = $163,026.16

Cost / sq ft = $163,026 / 267256 sq ft = $0.61 / sq ft

• Annual Utility Costs ‐ Comparable School, Salt Lake Valley

Cost / sq ft= $0.86 / sq ft

of which: Electrical = 77%

Gas = 23%

• Yearly Operating Cost Savings

$0.86 ‐ $0.61 = $0.25 /sq ft

$0.25 /sq ft x 267,256 sq ft = $66,814.00 (29%) Annual Savings

UTILITY COST (First Year)

Hybrid GLHP Systems

• Cooling Load is out of balance with the Heating Load

• Property Area is insufficient

• Reduce First Cost of the Ground Loop by taking advantage of the Part Load Operation of the Building

Hybrid GLHP Systems

Cooling Load is out of balance with the Heating Load

• Clark County School District (Las Vegas)

60% ground loop plus fluid cooler allows for winter, spring and fall operation on ground loop but runs a fluid cooler at peak loads.

• Lincoln Public Schools

Boiler hybrid to eliminate anti‐freeze and the 30% pumping penalty from anti‐freeze.

Hybrid GLHP SystemsCooling Load is out of balance with the Heating Load

Property Area is insufficient

Hybrid GLHP Systems

Take Advantage of Part Load Operation

Commercial Building Loads are only 50% or less of the Peak Load

for 80% ‐ 90% of the Year

Hybrid GLHP Systems

Take Advantage of Part Load Operation

50% of the hours In the year

27% Flow

80% of the hoursIn the year

54% Flow

552 GPM System (2.8 GPM/ton) with VFD Pumping

Hybrid GLHP Systems

Hybrid GLHP SystemsTake Advantage of Part Load Operation

Bin Weather Data: 8760 Hours/Year

205 Hours or 2.3%

Hybrid GLHP SystemsTake Advantage of Part Load Operation

Cooling Tower Project

Project name: Las Vegas Motor Speedway

Description: Media Center64,000 Sq. ft.Vertical Loop w/ Cooling Tower

Ground Temperature: 73.5 – 77.5ºF

Cooling load: 4,500,000 BTUH (375 tons)EFLH (cooling): 1325 ‐ 1000

Heating load: 2,640,000 BTUH (220 tons)EFLH (heating): 400

Hybrid GLHP Systems

Hybrid Loop Field W/ Cooling Tower

Loop Details Hybrid Full Geo

Number of bores: 150 563

Depth of bores: 400 feet 400 feet

Bore hole spacing: 25 feet 25 feet

Loop field installed costs: $ 780,000 $ 2.1 million

Building energy consumption/yr: $ 98,000 $ 92,700

Maintenance costs / yr: $ 11,856 $ 8,250

Summary

Hybrid Loop installed costs reduced by $ 1,320,000

Operating costs increased by $ 5,300 / yr.

Maintenance increase $ 3,606 / yr.

Hybrid GLHP Systems

Hybrid Loop Field W/ Cooling Tower

Loop Details Hybrid Full Geo

Number of bores: 150 563

Depth of bores: 400 feet 400 feet

Bore hole spacing: 25 feet 25 feet

Loop field installed costs: $ 780,000 $ 2.1 million

Building energy consumption/yr: $ 98,000 $ 92,700

Maintenance costs / yr: $ 11,856 $ 8,250

Summary

Hybrid Loop installed costs reduced by $ 1,320,000

Operating costs increased by $ 5,300 / yr.

Maintenance increase $ 3,606 / yr.

Hybrid GLHP Systems

Turn Key Cost about $13 per ft of bore hole

Pond Loops

Spacer

Surface Water / Lake Loop

Great River Medical Center – Burlington, Iowa2002 ASHRAE Technology Award1500 Tons in a 15 Acre Man‐made Lake

Pond Loop

Ground Loop Software

SOFTWARE VENDOR

GLD2010 Gaia Geothermal

GLHEPRO 4.0 IGSHPA

ECA ELITE SOFTWARE, INC. BRYAN, TX

Geo CALC FERRIS STATE UNIVERSITY, BIG RAPIDS, MI

GchpCalc ENERGY INFORMATION SERVICES, Tuscaloosa, AL

GL‐SOURCE KANSAS ELECTRIC UTILITY, TOPEKA, KS

G L Design GBT, Inc., Maple Plain, MN

GS2000 Buildings Group, Natural Resources Canada

LUND Programs University of Lund, Sweden

Wright‐Loop Wrightsoft, Lexington, MA

75.5 Connected Tons of GLHP’s97/77 F Summer; 28 F Winter




1.19 Thermal Conductivity

74.6 F Ground Temperature



Alt # 1

Alt # 2

Alt # 3

Basis of Design

Loop Cost Impact

Basis of Design:60 bore holes x 305 ft per hole x $10/ftTotal: $ 183,000.00

Add for Alt #1:60 bore holes X 5 ft per hole = 300 bore ftPlus 8 holes X 310 ft = 2,480 bore ftTotal: 2,780 bore ft X $10/ft = $ 27,800.00

Add for Alt # 2:16 holes X 305 ft = 4,880 bore ftTotal: 4,880 bore ft X $10/ft = $ 48,800.00

Add for Alt # 3:60 holes X 10 ft per hole = 600 bore ftPlus 16 holes X 315 ft = 5,040 bore ftTotal: 5,640 bore ft X $10/ft = $ 56,400.00

Efficiency Effect on Ground Loop

Alt # 1

Alt # 2

Alt # 3

Basis of Design

Building and Heat PumpInformation

Ground and LoopInformation





Ground Loop Peak Water Temperature Design


Building and Heat PumpInformation

Ground and LoopInformation







Ground Loop Peak Water Temperature Design


If Guessing at 1.0 Thermal ConductivityGround Loop Software

Using correct 1.44 Thermal ConductivitySaved 9,708 feet of bore hole drilling


Hybrid with 20% BoilerReduces bore hole drilling by another 10,384 feet


Ground Loop Peak Water TemperaturesAre only for brief periods of time



Maximum Peak Loop Temperature in 30 years during the cooling mode


Loop Design Using Original Peak Loop Temperatures and the resulting WSHP Efficiencies


Modify the Peak Loop Temperatures resulting in new WSHP Efficiencies (19.4 EER versus 16.9 EER) at the system’s maximum peak. Now model the energy savings properly

GLD 2009

Maximum Average Loop temperature during the cooling mode is even lower than 80F

WSHP Basics – System Schematic

WSHP Basics – System Schematic

I told you this is

IMPORTANT

LEED‐NC Version 3.0

Energy and Atmosphere Credit 1: Optimize Energy Performance

Points are awarded for exceeding the prerequisite energy performance for the entire building

LEED‐NC Version 3.0

Energy and Atmosphere Credit 1: Optimize Energy Performance

Baseline ASHRAE 90.1 for GLHP: 13.4 EER

Most GLHP’s at AHRI Rating (77 F EWT):

17.0 EER to 30.0 EER

20 EER = 49% Increase

Life Cycle Costs

Life Cycle Costs

Life Cycle Costs

Life Cycle Costs

Installed Las Vegas Schools

Sep 09 - Aug 10 School Year

Usage (kWh) Area (SqFt)

Total Use

(kWh/SqFt)

NWCTA 548 2,105,712.83 217,000.00 9.7

Information Needed To Price the Ground Loop:


Building Loads

GLHP Efficiency

IMPORTANT

Model the Building Operating Efficiency Properly

Take Advantage of Tax Incentives

Commercial Ground LoopWater Source Heat Pump Systems

Documents

Other Names for Ground Loop - rockymtnashrae.com...Heat Recovery To OA AHU: 125 F Hot Water Water ‐to ... 3.412 (BTU/Whr) * W(watts) 4 x L(ft of loop) x Slope( F) Thermal Conductivity