Application of Geothermal Energy at UNH Organic Dairy

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Application of Geothermal Energy at UNH Organic
Dairy
By Paul Pellissier and Makenzie Benander


Cost and Efficiency
Goals and Needs
Technology
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Costs
Goals

• Well Drilling 5,000.00
• Heat exchanger 3,789.00
• New Milk Chilling Technology 5,000 00
• Radiant floor heating 7,000.00
• Installation 7,500.00
• Total 28,289.00

• To take the UNH Organic Dairy off-grid
• To cut costs for the farm
• Be more sustainable and efficient
• Create an example for other small New England
  farms
• Geothermal does not generate electricity, but
  uses the earths thermal energy for applications
  in heating and cooling

Needs That Can Be Met by Geothermal

• Expected pay back period of 4.03 years
• Requires very little maintenance when installed
  properly

Cost Effective
Cooled Water
Need (current) Annual Energy Input
(Million BTU) Farm Offices Heating
99.41 Residence Heating/Hot Water (oil)
112.34 Milk Chilling 42.84
Total 254.59 Annual
Dollars Spent 8,258.50
Hot Water
Need (W/ Geothermal) Annual Energy Input
(Million BTU) Farm Offices Heating
3.82 Residence Heating/Hot Water 13.41
Milk Chilling 7.79 Radiant Floor Cow
Lane 3.06 Total
28.08 Annual Dollars Spent 1,233.69
Wells

• Open Loop Systems
• Allows for water exchange with groundwater or a
  body of water
• Utilizes preexisting resources
• Traditionally used for bigger applications

How it Works
Applications

• Geothermal is based on the fact that at a certain
  depth, the earths temperature is constant all
  year
• In summer this temp. is cooler than the air temp.
• And in winter it is warmer
• Wells Water is drawn through underground piping
  (loops) to absorbs the earths heat
• Heat Pump located at the surface converts this
  hot water into useful energy

http//img2.timeinc.net/toh/i/a/green/geothermal-p
ump.jpg
Efficiency

• Radiant Floor
• Warm water from ground is pumped directly through
  tubing in concrete slab

• Once heated concrete slab can retain heat even
  without actively flowing water via circulation
  pumps
• Application in cow lane in winter will prevent
  icing and cow injury
• Heat Exchanger
• Can be used for heating or cooling
• Heating Warm water flows through coils, heating
  air which can be blown through traditional
  ductwork
• Cooling Reverse, takes heat and puts it into the
  water
• Milk Cooling
• Plate Heat Exchanger Pre cools milk
• Water Source Condenser water provides a more
  efficient heat sink than air.

• Coefficient of Performance ratio of heat
  provided per BTU of energy input
• Heat pumps can be purchased with COPs of 2.8 or
  greater
• Heat pump used in calculations had COP of 4.9
• In a period of ten years the geothermal system
  will save over 41,000.00

System Best Suited

• Open Loop wells
• Pre-cooling milk with plate heat exchanger
• Heat exchanger for residence
• Radiant floor heat for Farm Office and cow lane
  (to prevent icing)