|Ralph Liebing, RA, CSI|
Post Number: 641
|Posted on Wednesday, June 27, 2007 - 10:09 am: |
Our client wants us to investigate using LEED construction for a GMP project-- industrial processing plant.
Any one know of any LEED consultants in the Cincinnati, OH area, who could be used as a resource for us [this is our first venture with LEED}? Any other consultants that might be used?
Also any good resources for available products, techniques, selection of points, etc.
|Richard A. Rosen, CSI, CCS, AIA|
Post Number: 11
|Posted on Wednesday, June 27, 2007 - 11:32 am: |
Contact the local USGBC chapter for a membership list and call the chapter director. They should know who the consultant members are. This is how I found an excellent consultant here in Philadelphia.
|Ralph Liebing, RA, CSI|
Post Number: 642
|Posted on Wednesday, June 27, 2007 - 12:44 pm: |
Thanks, Mr. Rosen, latched onto the Cincinnati Chapter web site.
|Posted on Thursday, September 13, 2007 - 12:45 pm: |
I am an Oregon Licensed Professional Engineer and the principal engineer for Eager & Associates. I have extensive experience in building design and am currently designing a Solar Demonstration and Test Facility. My primary interest at this time is in minimizing the temperatures of materials that underlie standing seam metal roofing. Unisolar photovoltaic laminate will be bonded to the bottom of the pans. The efficiencies of photovoltaic systems are related inversely to their cell operating temperatures. There appears to be nothing reported on the best type of roofing underlayment material to contribute to this objective. I thought that we could get some experts to present their opinions and possibly applicable research results in this forum to resolve this question.
Walt Eager, PE
|Joel McKellar, Assoc. AIA, LEED AP|
Post Number: 9
|Posted on Thursday, September 13, 2007 - 03:47 pm: |
One of my coworkers and I were wondering why there aren't more combined solar PV and water heat systems. The PV cells are essentially black, and if you run water underneath you are essentially creating a heat sink that is a win win. You pull the heat away from the panels while creating preheated water.
Has this been done already and we simply haven't heard about it, or is there some other reason that would make this fail that I'm not aware of.
Thanks and good luck...
Post Number: 210
|Posted on Friday, September 14, 2007 - 10:05 am: |
That sounds like a good idea, but might involve some technological development to realize. If its time has not yet come, a simpler approach might be to use a structural standing seam roof that is self-supporting between purlins (hence no need for an underlying deck), provide ample eave-to-ridge ventilation under the deck, and specify that the underside of the roof panels be painted black, so as to radiate as much heat as possible to the vented space underneath.
If I remember from physics class, that would make the underside of the roof panels a "black-body radiator"--the opposite of the increasingly popular white or aluminum "radiant barrier" coatings intended to prevent heat buildup in attics.
|Walter James Eager, PE|
Post Number: 2
|Posted on Wednesday, September 19, 2007 - 07:16 pm: |
Joel, yours is a good idea. Others have suggested it. The Solar Test and Demonstration system that I described above will have PV amorphous silicon laminate adhered to the bottom of standing seam panels at the sides of the roof where wind forces are highest and framed polycrystalline modules in the center. The latter will be clamped to the standing seams. This concentrates wind loading on the standing seam roof at the clamp locations. Thus, the reason for locating the framed module in the center where wind uplift pressure is much less.
I plan to run water in plastic tubing over the pans of the standing seam roof immediatel below these framed modules for the very reason you mentioned, to increase the efficiency of this PV system. Here accidental water leakage would have little or no adverse effect. This is not practicable for the roofing panels to which PV laminate is bonded as this will shade the laminates from the sun and reduce, not increase, the efficiency of this PV system. An alternate would be to install water piping inside the attic, below these panels. This would incur a higher risk of damaging leakage. However, with careful quality and operational control, including system drainage during freezing weather when there is insufficient solar input, it could be done. The freezing risk could also be controlled by using propylene glycol in a closed loop and transferring its heat to potable water in a heat exchanger. This is what Solarhart(recently acquired by Rheem) does in some of its solar hot water heaters such as the one that is now installed on the roof of my Solar Test and Demonstration Facility. At some point I might add this dual purpose system to the laminate panels and see if it provides an economic solution. This would make the PV laminate system more efficient by lowering its operating temperature and conserve energy by providing hot water as a by-product. Bob Woodburns ideas for cooling laminate systems that are installed on purlin-supported roofs are also very good.