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Regular City Council Meeting Monday,March 25, 2013 Page 24 referenced additional steps outlined in State Statute for the City Council to take before any actual award of a project, including notice requirements and publishing some of the data. In response to Councilmember Willmus, Ms. Lundberg advised that the typical life expectancy for this solar installation was forty (40) years, with standard mod- ule warranties for 20-30 years. Ms. Lundberg reviewed the laboratory testing for this particular product by the National Renewable Energy Labs under extreme lifestyle and weather conditions, with the silicone modules exceeding expecta- tions through 100 years of extreme conditions without exception. Ms. Lundberg noted the composition of the glass meant to be outside and withstand hail; and all wires protected in channels; with the inverters guaranteed for ten (10) years, with only modest operational expenses. Regarding the condition of the existing roof with this installation, Mr. Schwartz advised that this was the rationale for installation on the newer roof portions of the designated buildings; with approximately 25,000 square feet needed for each system and allowing for other rooftop equipment as well. Ms. Lundberg noted the need for actual roof space of approximately 5,000 square feet for each 40 KW installation. Discussion ensued regarding snow loads and requirements of the installation pro- cess, with oversight and design by both electrical and structural engineers and part of Powerfully Green's due diligence and accomplished through spreading out nominal ballast and adding for dead loads. Further discussion included other possible ground and/or rooftop applications in- cluding the new fire station and future park shelter construction; additional cost for ground mounts based on soil type and other considerations, with the City of Red Wing used as an example of such application; and how snow reacted to the installation and was addressed through angles of the panels with the onus on Powerfully Green to estimate conservatively to address those load based on this type of climate and continued use; and ability to access the roof through this in- stallation procedure, using concrete blocks and not permanently attaching the panels to the roof itself, but through use of ballasts and space between rows al- lowing for access. Additional discussion included staff discussions with the City's roofing contractor and existing warranty on the membrane with no impact to that warranty; the City's current energy use lower than some other public agencies and applications based on the rates of KW hours; ability to move the array— at the City's cost of between $7,000 to $10,000 — to facilitate future roof replacements; and the need to take those costs into consideration for the City's future CIP needs.