Twenty‐eight 327 W SunPower solar panels which should generate ~ 10,000 kWh/year for at least 25 years.
Module type 327 Watt
Derate factor 0.61
Cell type Monocrystalline
Inverter type Line
Power output warranty 95% for first 5 years, -0.4%/year max degradation to year 25
SunPower is an American* company, a leader in the solar field, and makes panels with the highest energy production efficiency. In addition, SunPower panels are unique in providing a 25-year warranty on the product, replacement labor and linear power production. (Other companies offer a 10-year product warranty and 25-year linear power production warranty.) We also like what we see about SunPower's commitment to socially responsible business practices.
We solicited bids from three companies and are continuing negotiations with two of them. Both are local companies with years of experience and a solid reputation. They are members of the NC Sustainable Energy Association and we will have an NABCEP certified installer working on site, both credentials which the NC Clean Energy Technology Center (formerly the NC Solar Center) recommended to us.
Electricity generated will be sold to Duke Energy Progress through net metering which will accrue to the congregation’s electric bill. We estimate that the congregation's annual electric bill will reduce from $2000.00 to $1000.00.
ARCHIVAL NOTE: Our first year of bills show that we did save $1000.
Estimated system cost: $37,000
Cost per kWh over 25 yrs = $0.10 (calculation incorporates NC tax credits)
Roof The roof of the Vaughan Fellowship Hall was last replaced in 1995 and will need to be replaced prior to panel installation. This will add $4,865.00 to the total project cost which will be paid for from reserved funds of the Justice in a Changing Climate Task Force.
Maintenance All providers say there is little maintenance. Rain washes the panels; we can blow off leaves if they clump. We'll do a visual inspection from time to time to see if anything looks odd – for instance, bees nesting in the inverter box. Any sudden declines in energy production which could signal a problem will be noticeable as we track our electricity production.
SunPower arrays are fully warranted for 25 years. Inverter is warranted for 10 years and we can expect to replace it midway through the life of the system. Replacement cost for inverter is $2500. A 2-5 year warranty on installation will cover the initial period. If equipment is going to fail, it is likely to be in the first 2 years.
Insurance We're checking with CUCC's insurance company to determine if there will be additional costs related to the installation of the solar array.
|Solar panels will go on the wing on the left,|
adjacent to the vegetable garden and parking lot.
Roof of the fellowship hall of Community United Church of Christ, which is at 814 Dixie Trail, Raleigh The roof is south-facing and solar access is unobstructed because of the parking lot.
Target operational date
Before Dec. 31, 2015 (the final date the tax credits are available)
ARCHIVAL NOTE: The array began generating electricity October 15, 2015.
SunPower is incorporated in the U.S. with global headquarters in Silicon Valley, CA. They have subsidiaries around the world. The French oil & gas supercompany Total acquired a 66% stake in SunPower Corporation in the same year that SunPower bought Total subsidiary Tenesol.