1. Abbas Shirian, PE Certified GeoExchange Designer
Life Cycle Cost
Abbas Shirian, PE
Certified GeoExchange Designer

2. Life Cycle Cost Analysis
“to evaluate all cost factors including first cost, operation, maintenance, replacement, and estimated energy use over a period of years for alternatives that equally satisfy functional requirements”.

3. Initial Cost & Design Variables
Equipment – Standard Efficiency or High Efficiency
Drilling cost - Borehole Depth, Pipe Size & Site Conditions
Piping Accessories
Outside Air & Ventilation System
Distribution & Pumping System
System Design
Controls System
Value of Floor Square Footage For Mechanical Rooms
Additional Cost for Structural Reinforcement
Additional Cost for Roof Access and Repairs
Additional Cost for Sound Proofing

4. Service Life & Replacement
Life Expectancy of HVAC Equipment
Life of Ground Loop Heat Exchanger
Life of Water Distribution/Equipment
Life of Air Distribution System
Life of Control System

5. Energy Costs Utility Structure of Electric Rates
Natural Gas and Fuel Cost
Inflation Rate
Equipment Efficiencies
Pumping Efficiency

6. GSHP & Gas/Elec HVAC Heating Energy Cost

7. Ground Source Heat Pump Electricity at $0.08/kWh & cop at 3.7
$0.08/kW x kW/3412 Btu x 100,000 Btu/therm x 1/cop =
$0.63/therm or $6.30/MMBtu
Gas/Electric HVAC System
Natural gas at $0.90/therm & 80% efficiency
$0.90/therm x 1/efficiency =
$1.13/therm or $11.30/MMBtu

8. Operating, Maintenance and Replacement Costs
ASHRAE
Mean’s Handbook
Equipment Manufacturers
Contractors
Owner’s O&M

9. Salvage Value Zero out at end of life for all alternatives
Ground Heat Exchanger Salvage Value

10. Cost of Money Depreciation Method Energy Cost Inflation Rate
Interest Rate
Percent Financed
Income Tax Rate
Study Life
Depreciation Life

11. Typical Financial Cost
Life of Analysis yrs
Cost of Borrowing Money 5-10%
Inflation %
Electric Energy Escalation 2-3%
Natural Gas Energy Escalation 3-5%
Tax Rate %
Cost of Insurance %

12. HVAC First Cost ($/sq. ft. ) Based on 77,000 sq. ft
HVAC First Cost ($/sq.ft.) Based on 77,000 sq.ft. school & 220 ton cooling
Geothermal Heat Pump ($2000/borehole) $25.22
Geothermal Heat Pump ($3000/borehole) $28.08
Water Source Heat Pump $22.81
VAV, AHU & TU/HW (Water Cooled Chiller) $30.04
VAV, AHU & TU/HW (Air Cooled Chiller) $27.85
Packaged Rooftop DX/Gas $20.39
Indoor Air Washer &HW Heating $28.85
Fan Coil (4- Pipe) (Water Cooled Chiller) $28.68
Fan Coil (4- Pipe) (Air Cooled Chiller) $26.49

13. Real Estate/Structural Savings
No mechanical rooms to house boilers or chillers with geothermal and air-cooled unitary
No fan rooms or penthouses with geothermal heat pump (horizontal) and 4-pipe fan coil unit systems

14. Annual Maintenance Cost ($/Ton)
Geothermal Heat Pump $67.24
Water Source Heat Pump $70.45
VAV, AHU & TU/HW (Water Cooled Chiller) $43.23
VAV, AHU & TU/HW (Air Cooled Chiller) $40.85
Packaged Rooftop DX/Gas $59.24
Indoor Air Washer & HW Heating $70.45
Fan Coil (4- Pipe) (Water Cooled Chiller) $56.04
Fan Coil (4- Pipe) (Air Cooled Chiller) $53.23

15. Life Cycle Cost Geothermal Heat Pump Water Source Heat Pump
VAV, AHU & TU/HW (Water Cooled Chiller)
VAV, AHU & TU/HW (Air Cooled Chiller)
Packaged Rooftop DX/Gas
Indoor Air Washer & HW Heating
Fan Coil (4- Pipe) (Water Cooled Chiller)
Fan Coil (4- Pipe) (Air Cooled Chiller)

16. QUESTIONS & DISCUSSIONS