5/19/2009
Green Building Expo & Get Green Business Conference

Geoff Greenfield, President, Third Sun, Solar & Wind  www.third-sun.com
Eric Cole, GeoSource  www.geosourceone.com

Installing Renewable Energy in your Project – Do’s & Don’ts of installing PVs and Geothermal

Solar Electricsolarhand

  1. Goals
    1. Visibility for recognition
    2. Designed around
      1. Amount energy need
      2. Roof #1 driver
      3. Amount on money
      4. 10 watts per sqfoot
      5. Gross cost 9,000.00 per kw
        1. Net cost 2,500 per kw
        2. Incentives are going down
        3. 1,200 kwh/year
        4. Web site:  http://pvwatts.org/
        5. Solar pathfinder software to determine the amount of shade.
        6. Roof loading, uplift
        7. 5 lbs / sf weight
        8. Federal tax credit is 70% of  cost, need to look at
        9. Write off the first year, plus in taxes: accelerated cost deprecation
        10. State of Ohio grants for areas in AEP areas.
        11. Commercial $150,000 dollars state credit.
        12. SB 221 would be possible change to increase grants and pay back, know in June
        13. PPA – Power Purchase Agreements (sell of power by a board).
        14. Pitch 26 degrees ideal, (flat to lateral possible)
        15. Axis: south 15 deg +/- (true solar south)
        16. Crystalline is typical type of panel, best for roof mounted
        17. Specify fully flash for pitched roof.
        18. Flat roofs are typically 10-13 degrees, 13 best in ohio do to the balance between shading and sun exposure.
        19. Must remove panels when replacing the roof  based on roof life
        20. More panels is a better investment than a tracking panel
        21. DC output of the solar must be converted to AC power.
        22. Monitoring on I phone or web base.

Solar Thermal

  1. Need a napsap installer to achieve Grants
  2. If you make the system big enough for the winter, you are over sizing for the summer.
  3. Size for the summer, so there is not assessed construction
  4. Glycal is used in Ohio over water in the system.
  5. Provides 60% to 70% of the water heating
  6. Used for preheating
  7. Used for heating in the floor.
  8. Solar Thermal is less expensive install than solar electric
  9. Flat plat collector have 50% efficiency
  10. Evacuated tube collectors higher efficiency
  11. Systems
    1. Closed Loop – used for glycal system
    2. Drain back – for pools
    3. Steam Back – gets rid of hot water in summer
    4. Hot water for preheat or
    5. Pools do not qualify for Federal tax credits
    6. 90% of the cost for commercial projects
    7. Tilt angel at 30 deg to 50 deg.
    8. Curbing added to not void roof warranty.
    9. 30% tax credit, no cap.
    10. 5 year accelerated depreciation, plus additional for this year.
    11. Green Energy Ohio has a residential grant program.
    12. 15 year pay back for a 30 year system.
    13. PPA can be done for Solar Thermal. Helps pay for system.

Geothermal

  1. Geothermal 50% to 70% savings
  2. Qualifies for 10% commercial credit
  3. Qualifies for 17 LEED points
  4. Takes the heat out of the building and ejects it into the ground.
  5. Takes the heat out of the ground and puts it into the building.
  6. Designs
    1. Open loop – ejects water into a pond or well
      1. i.      More maintenance
      2. ii.      Least expensive
      3. iii.      Water in well should be drinkable right out of the well
      4. iv.      Use of a natural spring
  7. Closed loop
    1. i.      Horizontal
    2. ii.      Vertical
    3. iii.      Pond
  8. Sizing the system for the heat and cooling load.
  9. The geology of the site is a must to determine the amount of heat that can be stored in the site.
    1. i.      Earth can be over heated is loops oversized.
    2. ii.      Proper loop sizing
    3. iii.      Loop systems are oversized, but should not be way oversized.
  10. Commercial building are cooling dominant.
  11. Vertical systems need at least a 10’ by 10’ well.
  12. A system can be placed in any ground, but the system type is dependent on the geology of the ground.
  13. Call you’re OOPS company for underground utilities.
  14. There could be caves underground that would need to be filled.
  15. Well information is on the web for Ohio sites.
  16. Open loop need to know the number of gallons per minute, 3 gallons per minute typical.
  17. Need to know draw down of well, needs to be small.
  18. Closed loop
    1. i.      Closed loop systems create a mess on the site.
      1. Not as much an issue on new construction
        1. Need sump
        2. Need erosion protection.
        3. ii.      Damped soil systems are best for heat transfer.
        4. iii.      Depth of bedrock is need to know for vertical systems.
  19. Horizontal systems are 4’ to 5’ to 10’ deep. 10’ typical.
  20. Mud router system is the cheapest and messiest.
  21. Should be brought in on the job before any other trades.
  22. Casing is needed to prevent holes from caving in.
  23. Sonic drilling is most expensive but less messy.
  24. Horizontal
    1. i.      Horizontal direction drilling little damage to land.
  25. Ponds
    1. i.      300 feet max from building
    2. ii.      Pond 8’ deep or greater
    3. iii.      Nice to have the pond there for a year first
    4. iv.      ½ or larger for the pond
    5. v.      Should/must own the pond
    6. vi.      Can fish on pond
    7. vii.      Loops suspended above the bottom of the pond at all times.
      1. Higher than 20 to 30 years of sediment.
      2. viii.      Plate heat exchangers
        1. More expensive
        2. Can hang of a dock
        3. Good for smaller ponds
  26. For commercial rejected heat can be used to melt snow on sidewalks.
  27. Antifreeze
    1. i.      Menthol is highly corrosive, do not use.
    2. ii.      Poly propylene is best, can eat it.
  28. You can get all the hot water needs for summer use. Makes 5% to 10% in winter.
  29. Do not use PVC piping.
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