HomeMy WebLinkAbout017SPECIFYING GEOTHERMAL ENERGY in COLLABORATION WI
Pleasant Harbor Marina and Golf Resort & Spa
D
CC IEOVE
FEB 2 9 2012
JLP__ JEFFERSON COUNTY 1;0
DEPT OF COMMUNITY DEVELOPMENT
The intent of this report is to provide data to support a "low-temperature geothermal system" for
exchanging heat and cooling primarily through a horizontal closed loop GROUND TO WATER
source.
Geothermal systems use the earth's energy storage capability to heat and cool buildings and to
provide hot water. The earth is a huge energy storage device that absorbs 47% of the sun's
energy — more than 500 times the energy that mankind needs every year — in the form of clean,
renewable energy. Geothermal systems take this heat during the heating season at an efficiency
approaching or exceeding 400% and return it during the cooling season.
Today there are now more than 1,000,000 geothermal installations in the United States. The
current use of geothermal heat pump technology has resulted in the elimination of more than 5.8
million metric tons of CO2 annually.
Although Washington may not have wide utilization of geothermal, for the past 35 years there
have been strong efforts to advance geothermal use and development. This includes the State of
Washington's Geothermal Policy, RCW 43.140.010. Washington has a growing ground source
heat pump (GSHP) activity for low temperature geothermal energy. As shown in Table 1,
utilization of geothermal heat pumps grew by 35% from 2006 to 2007 (rated by capacity in tons).
Table 1. Geothermal Heat Pump Shipments to Washington State*
Year Rated capacity in tons
2006 2,203
2007 2,980
*From Geothermal Heat Pump Manufacturing Activities 2007, Energy Information Administration's
annual report14
Guidance in permitting ground source heat pumps is provided in the report A Regulatory Guide to
Low Temperature Geothermal Development in Washington 15 (WSU Extension Energy Program,
April 2009).
The U.S. Environmental Protection Agency has identified geothermal heat pumps as a
technology that significantly reduces greenhouse gas and other air emissions associated with
heating, cooling and water heating residential buildings, while saving consumers money.
Both vertical and horizontal closed loop systems are well accepted in the State of Washington
and follow a well defined regulatory process. The Pleasant Harbor development is well suited for
this technology and represents an excellent opportunity for the implementation of these systems.
GROUND and WATER SOURCE HEAT PUMP EXCHANGE:
The annual temperatures for south-central Jefferson County area of Brinnon and Quilcene,
Washington are generally quite moderate and vary from November through April from an evening
low of 28 degrees Fahrenheit to daylight high of 58 degrees Fahrenheit. From May through
October, an evening low of 38 degrees Fahrenheit to a daylight high of 80 degrees
Fahrenheit; however, the mean -average year round temperatures are most often a low of 40
degrees Fahrenheit and a high of 68 degrees Fahrenheit. Annual rainfalls are measured in the
area to vary from 48 to 51 inches per annum. This moderate wet climate is an ideal application
for a closed loop geothermal system.
Ambient temperature geothermal has been planned for the larger and smaller structures at
Pleasant Harbor Resort for both commercial as well as residential applications. A typical school
such as Lake Washington School saves in the order of +/- $66,000 per year by using GSHP.
Mechanical Engineers are motivated with these cost savings, as well as the elimination of
Chlorofluorocarbons (CFC's) found in most air-conditioning compressors. The sequestering of
the release of GHG emissions while providing for healthier cooling has been encouraged through
WSU Extension Energy Program.
The following diagrams illustrate both geothermal options:
The PRIME SOURCE OF EXCHANGE (68% of structures
The Design Criteria for the geothermal Systems proposed at the Pleasant Harbor Resort
development are based on combination of vertical, horizontal and surface water applications.
The goal is to provide the majority of the capacity through the large Kettle forming a surface water
heat exchanger. Geothermal water, that includes an environmentally friendly anti -freeze, is
pumped through a series of horizontal piping trenches that are 3 to 9 feet deep. The piping is
positioned in parallel lengths as determined by the number of pipes installed. The plastic pipes
connect to headers as they access to a SLINKY placed at the bottom of the polyethylene
lined 120 million gallon water Reservoir (known as Kettle B), before re -looping back to the
mechanical room Heat Pumps. Water is an excellent conductor for the exchange of heat and
cooling where heat is rejected to the water in the warm periods. Heat exchangers in this pond
may also be interfaced with a vertical borefield to increase the capacity of the ground heat
exchanger serving the Golf Terrace and Conference Center.
The SECONDARY SOURCE OF EXCHANGE (19% of structures).-
The
tructures):The Design Criteria for the second closed loop piping system services the 19% including the
Sea -View Villas along the south-east quadrant of the property that parallels Fairway 10. Again,
the horizontal piping follows the cercinate route leading to the 13 million gallons of contained
(lined) surface run-off water at the lowest point of the development. This pond is
approximately 18 feet in depth, and therefore, not subject to freezing beyond the surface.
The THIRD SOURCE OF EXCHANGE (13% of structures):
The Design Criteria for the third closed loop ground source system services the remaining
13% including the rehabilitated structures by the Marina as well as the Pleasant Harbor House,
The Reunion House, and the Harbor View House. The vertical closed loop system consists of
bores with 1" diameter high density polyethylene piping. As per regulatory requirements, all
bores are completely grouted form the bottom up using low permeability grout. The piping is then
tied together in a reverse return header configuration, ending within the mechanical room where
the heat pups are located. The borefield would be located adjacent to the buildings it serves.
COMBINED HEAT AND POWER (CHP).-
The
CHP):The Cogeneration produced energy of approximately 365 Kw also provides an auxiliary benefit to
enhance the British Thermal Units (BTU's) in collaboration with the geothermal production at
Pleasant Harbor Resort.
The prime location for Cogeneration (365Kw) is adjacent to the Waste Water Treatment Plant.
This Power Plant provides secondary energy on the occasion of a Black -Out of Mason County
PUD, and also provides primary energy for the pools, spas, and support for domestic hot water.
Because the waste heat is not thrown off to the atmosphere, the sequestering of tons of Green
House Gas benefits the environment.
SUMMARY: Proposed Geothermal Systems at Pleasant Harbor Marina and Golf Resort
Two geothermal technologies are proposed for the Pleasant Harbor development.
• District geothermal energy system using the recycled water storage ponds as a heat
exchanger
• Closed loop vertical borehole systems
Distributed geothermal heat pumps located in each unit will provide forced air heating and
cooling. Domestic hot water will be provided by de -superheaters on the heat pumps and
supplemented by electric hot water tanks.
Geothermal systems represent a savings to the Resort of 30 to 70% in the heating mode and 20
to 50% in the cooling mode compared to conventional systems as a result of "Geothermal Heat
Pump Systems being the most energy-efficient, environmentally clean, and cost effective space
conditioning systems available, according to the EPA."
G EoTI LITY
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