Attachment D-Preliminary Life-Cycle Cost Analysis LCCA rev 1.pdf

HVAC Life Cycle Cost Analysis Report

Base Elizabeth City Child Development Center Elizabeth City Coast Guard Base, North Carolina

CONTRACT NO 70Z05018DTRANSY01

ORDER NO. 70Z05025F43000001

CLIENT PROJECT NO. 12993422

SUBMITTED BY:

BCE Engineers

A Division of GFT

SUBMITTED TO:

US Coast Guard

DATE:

27 October 2025

Table of Contents

1 Introduction

2 Life Cycle Cost Analysis Inputs

2.1 General Site Description

2.2 Envelope Description

2.3 HVAC Description

2.4 Utility Rates ....................................................................................................................... Error! Bookmark not defined.

2.5 Economic Assumptions

2.6 Installation Cost and Service Life

2.7 Maintenance Cost

2.8 Domestic Hot Water Analysis

2.8 Energy Consumption and Energy Cost

3 Life Cycle Cost Analysis Results

Appendix A .................................................................................................................... A1

BLCC5 LCC Analysis Results ...................................................................................................................................................... A1

NIST BLCC 5.3-20: Summary LCC ............................................................................................................................................. A2

Alternative: Proposed HP Chiller with VAV Reheat ....................................................................... AError! Bookmark not defined.

Alternative: Ground Coupled Water Source Heat Pump .............................................................................................................. A4

Alternative: Ground Couple Heat Pump VAV with Reheat ........................................................................................................... A3

Appendix B .................................................................................................................... B1

Escalation Rates ......................................................................................................................................................................... B1

List of Tables

Table 1 – Proposed, Alternate, And Baseline Building Components

Table 2 – Alternatives And Proposed HVAC Components

Table 3 – Installation Costs And Service Life

Table 4 – Maintenance Costs

Table 5 – Energy Consumption And Cost Summary

Table 6 – Proposed, Alternative 1, And Alternative 2 LCC Results

Table 7 – Performance Cost Index Compliance Path ....................................................................................................................... B2

Table 8 – "Real" Electrical Escalation .............................................................................................................................................. B2

E-CITY CHILD DEVELOPMENT CENTER

HVAC LCCA

1 Introduction

This Life Cycle Cost (LCC) Analysis is an effort to document, plan, and decide this building's energy-related components. The energy analyst and architectural team have listed, discussed, and analyzed the envelope for this building. They have made decisions and assumptions about the roof, walls, floor, glazing, and doors and how these interact with the heating, ventilation, and air conditioning (HVAC) system and lighting systems. Decisions were made about the practicality, budget, and function of all these items, and the components analyzed best fit this facility and its constraints.

The proposed building's estimated energy consumption is less than the ASHRAE 90.1-2022 baseline energy consumption by 19.88% with no process loads included. The proposed building energy model energy cost is less than the ASHRAE 90.1-2022 baseline model energy cost by 46.98% with process loads. Alternate 1's building's energy model cost is less than the ASHRAE 90.1-2022 baseline model energy cost by 41.94% with process loads. Alternate 2’s building's energy model cost is less than the ASHRAE 90.1-2022 baseline model energy cost by 51.86% with process loads. The energy tool used to estimate building energy consumption was Trace700. The Proposed systems and both Alternate 1 and 2 building designs meet the EPACT requirement of 30% or more energy savings above the ASHRAE 90.1-2022 baseline energy model for a new project.

The proposed building design and its alternative building designs were analyzed for a 40-year life cycle using

BLCC5. The BLCC5 outputs were compared to ensure that a cost-efficient building design was selected.

2 Life Cycle Cost Analysis Inputs

2.1 General Site Description

CDC E-City is a single-story building. The child development center is a 24,629 ft2 building comprising mostly of early-childhood classrooms as well as office space, reception areas, a faculty break area, storage spaces, a comms room, a kitchen, a laundry room, and building utility rooms. The building is occupied during the day, 8 hours per day, five days a week. The minimum outside air requirement has been calculated per ASHRAE

62.1-2022. The building has a heating setpoint of 65 °F, with a cooling setpoint of 75 °F. During unoccupied hours, the HVAC systems revert to a "setback" mode wherein the heating and cooling setpoints are reset to conserve energy when that portion of the building is not being used.

2.2 Envelope Description

The child development center proposed building envelope consists of the following: Roof R-49 continuous insulation with a calculated U value of 0.02. Walls R-13 batt with R-10 continuous insulation with a calculated

U value of 0.076. Vertical glazing was modeled as fixed, nonmetal framed, double pane with a U value of 0.4 and an SHGC value of 0.32. Standard opaque swinging doors were modeled with a U-value of 0.352.

Alternative 1's and Alternative 2's envelopes are the same as the proposed envelope. Table 1 compares the

Proposed, Alternative 1 and Alternative 2 building envelope components and their overall U values. ASHRAE

90.1-2022 Baseline envelope values are also listed in the table below for comparison.

E-City Child Development Center

Table 1 – Proposed, Alternate, and Baseline Building Components

Component Proposed: Ground

Coupled WSHP

Alternative 1: HP Chiller

VAV w/Reheat

Alternative 2: GCHP

VAV w/Reheat

ASHRAE 90.1 -

2022 Baseline

Walls U=0.076 U=0.076 U=0.076 U=0.071

Roof U=0.02 U=0.02 U=0.02 U= 0.028

Vertical Glazing

(Windows)

U=0.4 fixed

SHGC=0.32

U=0.4 fixed

SHGC=0.32

U-0.4 fixed

SHGC=0.32

U=0.29 fixed

SHGC=0.4

Doors

(Swinging) U=0.352 U=0.352 U=0.352 U=0.370

Concrete Floor F=0.48 F=0.48 F=0.48 F=0.51

2.3 HVAC Description

The proposed HVAC system consists of a ground coupled heat pump (GCHP) and a dedicated outdoor air system (DOAS). Each space will have a ground-coupled water source heat pump located in the ceiling or closet space. These GCHP’s will recirculate zone air to provide heating and cooling for the space. The GCHP will allow for unoccupied, after hours heating and cooling without the need of the DOAS. The DOAS will provide ventilation air and collect return and exhaust air from the building. The return air will be pulled across an air-to-air heat exchanger to temper the ventilation air before being provided to the building. An electric hydronic boiler will be provided to back up the ground coupled heat pump during extremely cold weather.

An under floor radiant heating system will be provided in infant and pre-toddler care rooms and coupled with the GCHP and hydronic boiler.

Alternate 1’s HVAC system consists of a variable air volume (VAV) system with a full air-side economizer.

Each space or zone will have a VAV terminal recirculating the air to heat or cool the space. The VAV terminal will have a hot water reheat coil on the discharge to provide heating and will provide unoccupied, after hours heating without the use of the main air handler. The main air handler provides ventilation air that is heated/cooled/dehumidified and delivered to each space through the VAV terminals. Supply air temperature will continually be reset based on VAV terminal air volume feedback. Heating water will be generated by a high-efficiency, air to water heat pump. Heating water will be circulated to each VAV terminal, the under-floor radiant heat system, and the main air handler. Chilled water will be generated by the same high-efficiency, air to water heat pump and circulated to the main air handler for the purpose of cooling and dehumidification of the ventilation air.

Alternative 2’s HVAC system consists of a variable air volume (VAV) system with a full air-side economizer.

Each space or zone will have a VAV terminal recirculating the air to heat or cool the space. The VAV terminal will have a hot water reheat coil on the discharge to provide heating and will provide unoccupied, after hours heating without the use of the main air handler. The main air handler provides ventilation air that is heated/cooled/dehumidified and delivered to each space through the VAV terminals. Supply air temperature will continually be reset based on VAV terminal air volume feedback. Heating water will be generated from a high-efficiency ground-coupled water to water heat pump (GCHP). Heating water will be circulated to each

VAV terminal, the main air handler, and the under-floor radiant heat system. Chilled water will be generated by the same GCHP and circulated to the main air handler for the purpose of cooling and dehumidification of the ventilation air. Chilled water will also be circulated to the VAV terminals for the purpose of cooling the space.

Per ASHRAE 90.1-2022 G.1.2.2, "Neither the proposed building performance nor the baseline building performance are predictions of actual energy consumption or costs for the proposed design after construction. Actual experience will differ from these calculations due to variations such as occupancy, building operation and maintenance, weather, energy use not covered by this procedure, changes in energy rates between the design of the building and occupancy, and the precision of the calculation tool."

The proposed system, alternative 1, and alternative 2 HVAC definitions and efficiencies are listed below in

Table 2. ASHRAE 90.1-2022 baseline HVAC definitions and efficiencies are also listed for comparison.

Table 2 – Alternatives and Proposed HVAC Components

Component

Proposed: Ground

Coupled WSHP

Alternative 1: Chiller

VAV w/Reheat

Alternative 2: GCHP

VAV w/Reheat

ASHRAE 90.1 -

2022 Baseline –

System 5

Heating

Water Source Heat Pump –

3.7 COP

Air Source Heat Pump – 2.52

COP

Water Source Heat Pump – 3.7

COP

Gas Fired Furnace – 75%

EFF

Cooling WSHP – 18 EER ASHP – 9.3 EER WSHP – 18 EER PSZ – 10.57 EER

Economizer No No No Yes, @75ºF

Heat

Recovery* 0.76 sensible/0.74 latent 0.76 sensible/0.74 latent 0.76 sensible/0.74 latent None

Supply Fan

(kw/cfm) WSHP=0.0008 ASHP SF=0.0008 WSHP=0.0008

Packaged Rooftop VAV

SF=0.00113988

Safety Factor

1.0 Heating

1.0 Cooling

1.0 Heating

1.0 Cooling

1.0 Heating

1.0 Cooling

1.25 Heating

1.15 Cooling

Equipment

Schedule 8 Hrs/day, 5 days/week 8 Hrs/day, 5 days/week 8 Hrs/day, 5 days/week 8 Hrs/day, 5 days/week

2.4 Utility Rates

The electric energy rate used for the economic analysis is $0.0933 per kWh. The natural gas rate used for the economic analysis is $1.20 per therm. Utility rates for both electricity and natural gas were current rates received from the US Coast Guard and US Government for the area of Elizabeth City, North Carolina in 2025.

2.5 Economic Assumptions

The economic assumptions made in this analysis are based on the values in the current version of BLCC5_3-

24. The current BLCC5 economic assumptions extend to 2065. Years beyond 2065 included in this analysis are assigned the "Remaining" Escalation Rate. "Real" escalation rates are as noted in Appendix B.

2.6 Installation Cost and Service Life

The HVAC equipment costs shown below were provided by “CostWorks 2021”. The equipment service life data was estimated from the "Energy Life-Cycle Cost Analysis, Guidelines for Public Agencies." A summary of the installation costs and service life for the proposed building system and the alternative building systems is listed below in Table 3.

Table 3 – Installation Costs and Service Life

Category Service Life Proposed: Ground

Coupled WSHP

Alternative 1: Chiller VAV w/Reheat

Alternative 2: GCHP VAV w/Reheat

Ductwork 50 $184,718 $184,718 $184,718

WSHP 19 $254,150 $0 $0

Hydronic Piping 50 $73,887 $147,774 $147,774

Hydronic Circ. Pump 25 $41,950 $49,900 $41,950

Electric Hydronic Boiler 15 $35,000 $44,000 $35,000

4-Pipe VAV AHU 20 $96,600 $285,000 $285,000

Controls 15 $67,730 $67,730 $67,730

Enthalpy Wheel Heat

Exchanger 20 $29,700 $0 $0

Ground Loop Heat

Exchanger 50 $394,064 $0 $394,064

VRF Condensing Unit –

1.5 Ton 20 $2,475 $2,475 $2,475

VRF Indoor Unit – 1 Ton 20 $8,025 $8,025 $8,025

Radiant Floor Piping 50 $69,563 $69,563 $69,563

Fan Powered VAV

Terminal 20 $0 $155,670 $166,790

Air Cooled Chiller 20 $0 $245,000 $0

Water Cooled Chiller 20 $0 $0 $210,000

Totals $1,257,862 $1,259,855 $1,603,089

2.7 Maintenance Cost

A summary of the proposed and two alternate system's maintenance costs are listed below in Table 4. The maintenance costs for each system alternate are estimated from "RS Means Facilities Maintenance and

Repair 2021".

Table 4 – Maintenance Costs

Category Proposed: Ground

Coupled WSHP

Alternative 1: Chiller

VAV w/Reheat

Alternative 2: GCHP VAV w/Reheat

WSHP $9,775 $0 $0

Hydronic Circ. Pump $246 $246 $246

Electric Hydronic Boiler $435 $435 $435

4-Pipe VAV AHU $645 $1,290 $1,290

Controls $290 $290 $290

VRF Condensing Unit – 1.5 Ton $370 $370 $370

VRF Indoor Unit – 1 Ton $880 $880 $880

Fan Powered VAV Terminal $0 $7,056 $7,560

Air Cooled Chiller $0 $1,475 $0

Water Cooled Chiller $0 $0 $1,175

Annual Totals $12,641 $12,042 $12,246

2.8 Domestic Hot Water Analysis

The design team evaluated two electric water heating systems and compared them to the ASHRAE 90.1 2022

Appendix G Baseline. The proposed system utilizes an air source heat pump water heater that would operate in a single pass lift to meet the storage temperature of 140F, with a back-up electric boiler for usage in extreme cold weather. Alternative 2 is an air source heat pump system that operates in the same manner as the proposed system to meet the 140F storage temperature. A PV array is supplied to work as a supplemental renewable energy for the air source heat pump and an electric boiler is provided to aid in heating water in extreme cold weather. Each alternative was run under the assumption that the child development center uses 1980.6 gallons of water per day, calculated at 2.4 gallons/meal for 352 people a day, plus an additional

264 gallons/day for lavatory water usage and an additional 27 gallons/day for sink water usage. Details and costs for each system are shown in Table 5 below.

Table 5 – Domestic Hot Water Generation Alternatives

Since the proposed system showed the lowest life cycle cost, this system was paired with all of the HVAC alternatives in the full LCC analysis. The Appendix G baseline case included the gas-fired DHW system.

Alternative 1:

ASHP Alternative 2: ASHP w/30% PV

ASHRAE 90.1 2022 Appendix

G Baseline (Gas-Fired Water

Heater)

Daily Hot Water Use (gal/day) 1980.6 1980.6 1980.6

Incoming Cold-Water Temp 50 50 50

Hot Water Storage Temp 140 140 140

Building HW Energy

Requirement (kWh/year) 52,451.6 36,716.1 6,713 therms

Thermal Efficiency of DHW

System 3.0 COP (47F) 3.0 COP (47F) .8 Et

Cost of Fuel $0.0933/kWh $0.0933/kWh $1.20 / therm

Annual Energy Cost $4,894 $3,425 $8,056

Equipment Spec

400 MBH ASHP

60 kW Electric Swing

Tank

500-gallon storage

400 MBH ASHP

60 kW Electric Swing Tank

11 kW PV Array

500-gallon storage

(1) 500 Gallon 750MBH Gas-Fired

Water Heaters

Equipment First Cost $90,300 $117,800 $47,800

Annual O&M Cost $1,910 $2,100 $1,925

40 Year LCC $315,781 $328,368 $246,505

2.9 Energy Consumption and Energy Cost

Table 6 below summarizes the baseline, proposed, and alternative building designs' energy consumption and costs. The electric and natural gas utility rates were provided by the US Coast Guard for the area of Elizabeth

City. This analysis's electric utility rate is $0.0933 per kWh, while the natural gas was taken from an average commercial rate of $1.20 per therm. These energy model results and costs are used in the BLCC5 40-year life cycle cost analysis.

Table 6 – Energy Consumption and Cost Summary

Component Proposed: Ground

Coupled WSHP

Alternative 1: HP

Chiller VAV w/Reheat

Alternative 2:

GCHP VAV

w/Reheat

ASHRAE 90.1 -

2022 Baseline

Fan energy 100.9 26.6 22.5 33.7

Heating Energy 120.3 132.9 124.6 536.5

Cooling Energy 26.2 113.3 66.9 71.4

Interior Lighting Energy 83.9 83.9 83.9 143.8

Pump & Aux Energy 4.8 2.4 13.3 5.5

Exterior Lighting 19.6 19.6 19.6 19.6

Total Energy Consumption (MBTU) 355.7 389.6 322.9 820.3

Electrical Energy Cost $9,724 $10,649 $8,828 $8,680

Natural Gas Energy Cost $0 $0 $0 $6,033

Total Energy Cost $9,724 $10,649 $8,828 $14,713

Energy Consumption

Average (kbtu/sqft-yr)

14.44 15.82 13.11 33.29

Maximum Unmet Hours 0 heating

0 cooling

0 heating

0 cooling

0 heating

0 cooling

0 heating, 0 cooling

* All energy values shown in Table 5 are in MBTU (millions of BTU).

3 Life Cycle Cost Analysis Results

The BLCC5 40-year life cycle detailed LCC report for the proposed building design and the alternative building designs is provided in Appendix A. The 40-year life cycle costs are summarized in Table 7 below.

Table 7 – Proposed, Alternative 1 and Alternative 2 LCC Results

System LCCA 40-year Costs

Proposed: Ground Coupled WSHP $2,081,568

Alternative 1: HP Chiller VAV w/Reheat $2,307,853

Alternative 2: GCHP VAV w/Reheat $2,597,810

Table 8 – Performance Cost Index Compliance Path

Components

Proposed: Ground

Coupled WSHP

Alt 1: HP

Chiller VAV w/Reheat

Alt 2: GCHP

VAV w/Reheat

ASHRAE 90.1-2022

Appendix G System 5

BBP (Baseline Building

Performance) - - - $14,713

BBUEC (Baseline Building

Unregulated Energy Cost) - - - $22,430

BBREC (Baseline Building

Regulated Energy Cost) - - - $7,717

BPF (Building Performance

Factor) - - - 0.53 (Other)

PBP (Proposed Building

Performance) $9,724 $10,649 $8,828 -

PCI (Performance Cost Index) 0.66 0.72 0.60 -

PCIt (Performance Cost Index target) - - - 1.25

PI (Percentage Improvement

+30% = EPAct Compliance) 46.98% 41.94% 51.86% -

Page A1

Appendix A

BLCC5 LCC Analysis Results

Page A2

NIST BLCC 5.3-24: Summary LCC

Consistent with Federal Life Cycle Cost Methodology and Procedures, 10 CFR, Part 436, Subpart A

Page A3

Alternative: Proposed Ground Coupled WSHP

LCC Summary

Page A4

Alternative: HP Chiller VAV w/Reheat

Page A5

Alternative: GCHP VAV w/Reheat

Page B1

Appendix B

Escalation Rates

TABLE 9 – "REAL" ELECTRICAL ESCALATION

RATES

*"Real" Analysis does not include inflation.

From Date Duration Escalation

April 1, 2024 1 year 0 months -1.96%

April 1, 2025 1 year 0 months -2.06%

April 1, 2026 1 year 0 months -2.13%

April 1, 2027 1 year 0 months -1.70%

April 1, 2028 1 year 0 months -0.85%

April 1, 2029 1 year 0 months -0.40%

April 1, 2030 1 year 0 months 0.40%

April 1, 2031 1 year 0 months 0.20%

April 1, 2032 1 year 0 months 2.17%

April 1, 2033 1 year 0 months 1.37%

April 1, 2034 1 year 0 months -0.14%

April 1, 2035 1 year 0 months 0.47%

April 1, 2036 1 year 0 months 1.34%

April 1, 2037 1 year 0 months 1.65%

April 1, 2038 1 year 0 months 0.61%

April 1, 2039 1 year 0 months 0.53%

April 1, 2040 1 year 0 months -0.21%

April 1, 2041 1 year 0 months -0.26%

April 1, 2042 1 year 0 months -0.29%

April 1, 2043 1 year 0 months 0.11%

April 1, 2044 1 year 0 months 0.53%

April 1, 2045 1 year 0 months 0.08%

April 1, 2046 1 year 0 months -0.05%

April 1, 2047 1 year 0 months -0.45%

April 1, 2048 1 year 0 months -0.50%

April 1, 2049 1 year 0 months -0.90%

April 1, 2050 1 year 0 months -0.48%

April 1, 2051 1 year 0 months -0.49%

April 1, 2052 1 year 0 months -0.49%

April 1, 2053 1 year 0 months -0.46%

April 1, 2054 Remaining -0.57%