Sun The earth can absorb nearly half of the sun s energy. The ground stays a relatively constant temperature through the seasons, able to absorb the rejected heat in summer and release this heat stored back in the winter. Geothermal Best Practices and Ownership Brought to You by: Dan Walsdorf of Advanced Custom Geothermal and The Wisconsin Geothermal Association. Learning Objectives for this session Understand how geothermal works. Proper applications, components, design and energy analysis challenges of every geothermal system. Types of geothermal systems. System performance vs alternatives. Understand the values of each component and the useful life. Examples of installation with Geothermal. Where is the future of geothermal. 1
Key Components to Achieve a Successful Geothermal System Geothermal Heat Pump Energy Delivery System Geothermal Earth Loop Liquid Loop Heat-Exchange Medium Qualified Installing Professional Qualified Designing Professional Consumer Research 2015 Department of Energy Goal 2
Interesting Facts According to the Environmental Protection Agency (EPA), GeoExchange technology is the most energy-efficient, environmentallyclean and cost-effective space conditioning system available. Federal Tax Credits (residential) currently in place allows for a 30% tax credit through December 2016. What Is Geothermal Energy? Geothermal -- Heat from the earth Normal earth temperatures Earth absorbs 47% of the sun s energy that reaches it Available everywhere Not associated with geysers Earth Temperatures A few feet below the surface, earth temperatures remain relatively constant and moderate. Ground temperatures are much milder than average monthly air temperatures. 3
Energy Source During the heating season, the earth serves as a heat. (HE - Heat of extraction) During the cooling season, the earth serves as a heat. (HR - Heat of rejection) Energy Source During the heating season, the earth serves as a heat Source. (HE - Heat of extraction) During the cooling season, the earth serves as a heat Sink. (HR - Heat of rejection) 4
Ground Source Heat Pumps Heat pumps move energy from one location to another, instead of creating heat by burning fossil fuels, such as a gas furnace does. -- (like your refrigerator). Geothermal Heat Pumps use the earth to provide heating, cooling and hot water for your home. The Second Law of Thermodynamics Energy (heat) flows spontaneously from an area of high concentration (hot body) to an area of low concentration (cold body). Always hot to cold, never cold to hot Cooling is actually the removal of heat Ground Source Heat Pumps The heat moves through a liquid medium inside a loop system (Closed Loop) or through well-water (Open Loop) 5
Average Installed cost and future value of the earth loop Typical Pond Loop ~$700 $1000 /ton Typical Horizontal Loop ~$1100 - $1500 /ton Typical Bohr Loop ~ $1800-2200 /ton Typical Vertical Loop ~ $2200 2800 /ton (Prices may vary by soil, location and geography.) Open Loop Depends on many variables. What is the future value? Average Installed cost and the value of the Geothermal Heat Pump and system design. Machine ASHRE rated life 24.7 years (almost twice the rated life of any combustions system) Average Machine cost ~$8,000 however??? Design delivers lifelong comfort and is a one time investment. 6
HEATING Heating Operation COOLING 7
Geothermal has come a long way from the days of ignition and combustion. With Geothermal both comfort and efficiency are built directly in. Loop System Materials High Density Polyethylene Flexible Heat Fusion Capable Socket Butt Horizontal and Vertical 8
Horizontal Racetrack Design Individual Channel Loop Installation Vertical Bohr Installation 9
U-BEND at Bottom of Bohr Grout inserted from bottom to the top of Bohr. Directional Bohr Loop Installation 10
Pond Loop Requires minimum of ½ acre private land 9 feet deep at most shallow season of the year Flat Plate Heat Exchanger 11
HDPE Loop Pipe Benefits High density polyethylene pipe (life expectancy of over 200 years) Does not rust, rot, or corrode All connections are made by heat fusion 50 Year No Leak Pipe warranty 12
Equipment Performance Ratings ARI has designated the efficiency ratings for water-to-air heat pumps as: Energy Efficiency Ratio (EER) EER = BTU output divided by power watt input For cooling operation under steady state test conditions Coefficient of Performance (COP) COP = BTU output divided by BTU input For heating operation under steady state test conditions Cooling Performance Ratings Geothermal Air Source Heat Pump Air Conditioner 17-41 EER 10-15 EER 10-15 EER Heating Performance Ratings Geothermal (ground source) 3.5-6.0 COP Air Source Heat Pump 1.8-2.0 COP Fossil Fuel Furnace 0.80-0.95 COP Electric Furnace/Baseboard/Ceiling Cable 1.00 COP 13
Geothermal Water to Air 5 ton system - 3 thermostat 2011 control SCWBA zoning Parade of Homes - Domestic hot water desuperheater Total Sq. Feet = 4,949 -Heating load = 63,663Btuh -Cooling load = 41,306 Btuh Case Study #1 Cost to retrofit existing home with forced air geo system $17,685 Cost to replace conventional system with hybrid Gas $8,600 Difference between the two systems $9,085 Total Federal Tax Credit $5,305.50 Net Investment for Geothermal system after credits $3,779.50 For this home annual energy savings $900 The projected Break Even point in years 4.1 years 14
Case Study #2 Cost to retrofit existing home with radiant and forced air geo system $31,000 Cost to replace conventional system $15,000 Difference between the two systems $16,000 Total Federal Tax Credit $9,300 Net Investment for Geothermal system after credits $6,700 If your loan is at 6% it would add this amount to your payment ($56.94) This home has a monthly savings of $189.17 Created positive cash flow $132.23 The projected Break Even point in years 3.2 This home has projected Return on investment 6.5% This home has an annual projected HVAC bill of $1,355 What about the rated useful life of the equipment? Residual Value of the energy field? 15
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Geothermal Done Right! Requirements of HVAC Designer / Contractors: 1. ACCA Manual J (or Automated) Load Calculations Appliance Heat Gains Solar Heat Gain / Loss Occupancy Heat Gain Infiltration Rates and Building Envelope 2. ACCA Manual S (or Automated) Duct Calculations Duct gain or Loss Energy Flow and Distribution Questions? THANK YOU!!!!!!! 19