Subterranean Success: Geothermal Energy Powering Schools
Presented by:Jason Hukill, AIA, LEED AP
Today’s Learning Goal:
Geothermal Terminology / Systems
Benefits of Geothermal Power
Limitations of Geothermal Power
Common Misconceptions
Sample Projects
Questions / Answers / Discussion Forum
Subterranean Success: Geothermal in Schools
Geothermal: what is it?
Subterranean Success: Geothermal in Schools
Geothermal Terminology / Systems
A central heating and/or cooling system that pumps heat to or from the ground. It uses the earth as a heat source (in cold season) or a heat sink (in the warm season.)
Known by variety of names: Earth Energy, Geo-exchange, earth-coupled, or water source heat pumps.
Different System Types: Water loop, Deep Well, Earth Loop Systems
“Ground Source Heat Pump” is most common type in this region.
Subterranean Success: Geothermal in Schools
Ground Source Heat Pumps Take advantage of the moderate temperatures
in the ground to boost energy efficiency.
Should not be confused with traditional forms of geothermal power that use high temperatures.
Tempered water from ground well source is pumped to a heat pump unit (usually inside the building) and then forced through a vacuum refrigeration cycle to transfer the heat.
“Ground Source Heat Pump” is most common type in this region.
Subterranean Success: Geothermal in Schools
Implementing into your project Contact Geo-exchange surveyor to drill a test well / consult on findings for geo-
exchange potential of site.
Establish through master planning of site where geothermal fields will be located.
Establish a building connection point for loop system.
Ensure project team has adequate engineering experience on designing and specifying geothermal systems.
Calculate energy savings through modeling to assist in asset potential.
Give adequate mechanical space inside structure for equipment.
Monitor process and progress.
Subterranean Success: Geothermal in Schools
Typical Components
Bentonite Clay
Sand
Loop tubing
Routing Vault
Pump Unit
Well Field
Subterranean Success: Geothermal in Schools
Typical Components
Bentonite Clay
Sand
Loop tubing
Routing Vault
Drilling Rig/Crew
Well Field
Subterranean Success: Geothermal in Schools
Typical Components
Entry point for supply / return
Internal Water Piping
Water Source Heat Pumps
Ductwork Structures
Building
Benefits of Geothermal
Subterranean Success: Geothermal in Schools
Take advantage of the moderate temperatures in the ground to boost energy efficiency. Free energy from mother earth.
50+ year lifespan on ground loop exchange system.
25-30+ year lifespan on equipment (inside)
Can be installed under parking lots, sports fields/tracks, etc.
Lower operational costs of system. (life cycle cost advantages)
Typically can be staged along side other construction.
Subterranean Success: Geothermal in Schools
Lifecycle Cost Advantages
Resulting in:•Power savings•Energy savings•Pocketbook savings
Return of Investment (ROI)Typically between 6-8 years depending on design and geo-exchange capacity.
20%-60% more efficient than traditional systems used.
Mechanical Screening
Architectural screening not needed
Subterranean Success: Geothermal in Schools
Equipment Security
Exterior security of equipment not needed
After thought….
Subterranean Success: Geothermal in Schools
Limitations of Geothermal
Subterranean Success: Geothermal in Schools
Well field requires open space or land for installation.
Extremely limited to impossible for urban sites.
Initial staff shock. (you must train your maintenance staff)
Careful environmental conditions must prevail. Messy operation
Typical drilling rig operating
Common Misconceptions
Subterranean Success: Geothermal in Schools
Too expensive….
Project needs to be near steam or fault areas….
Complexity of systems….
Added mechanical controls too much…..
Environmental Concerns with drilling operations…..
Too “out there” for my building…..
Sample Projects
Subterranean Success: Geothermal in Schools
Blanchard High School
55,000 SFCompleted 2010’$15.2 mil
Geothermal systems costs:905k = 5.9% of budgetROI = est. 8 years
Subterranean Success: Geothermal in Schools
Shawnee Early Childhood Center
55,000 SFCompleted 2008’$6.5 mil
Geothermal systems costs:400k = 6% of budgetROI = est. 7 years
Subterranean Success: Geothermal in Schools
Shawnee Early Childhood Center
Geothermal systems costs:400k = 6% of budgetROI = est. 7 years
Subterranean Success: Geothermal in Schools
Geothermal well field installed under playground
Sapulpa Midtown Elementary
90,000 SFCompletion in 08-2011’$12.8 mil LEED for Schools (certification pending)
Geothermal systems costs:800k = 6.3% of budgetROI = est. 5 years
Well field installation under sports fields.
NorthwestLibrary35,000 SFComp. 09-2011’$8.4 mil
Subterranean Success: Geothermal in Schools
Educating the OccupantsEducation boards/displays can highlight a buildings sustainable features
Subterranean Success: Geothermal in Schools
Educating the Occupants
Other board examples:
Subterranean Success: Geothermal in Schools
Summary points to take with you….
Affordable
EFFICIENT 20%-60% more than base
Life cycle cost effective
System security / protection
Sustainable
Subterranean Success: Geothermal in Schools
Discussion
Questions
Comments
Thoughts / Aspirations
Subterranean Success: Geothermal in Schools
Thank you.
Subterranean Success: Geothermal in Schools