Nth Degree Solar Energy, a Grand Junction, Colorado based solar design and installation firm recently finished a commercial solar installation in Monte Vista, CO. Find it here.

Nth Degree Energy uses the Acme camera kit and PV Watts to do a custom designed solution that fits the customers needs.  Here is what an array shot looks like to determine the amount of sun hours a day:

Solar Analysis Chart

The solar array was installed on an empty field across a ditch from the house:

Grid-tied Solar PV electric system installation site

Here is a picture of the completed solar installation:

Installed Solar Electric Power Plant - 15KW

The system required two Sunny Boy 7000 inverters:

Grid-tied solar array inveter cross-connect

You can view the power plant here.

Description of location:
1: Latitude: 37.653 N Longitude: 106.660 W Elevation: 7750’
2: Declination: 9.8 deg E
3: Lowest Temperature -34deg F: Highest ambient Temperature 78 deg F
4: Total Electricity used/Year: 44,863 KHW Total Cost/Year $ 4,640.17
5: Panel Pitch: 35 Deg
6: Hours of Solar Radiation: 6.33 Hours /day fixed for summer

Picture of sunlight hours for House site: The site has 98% of sunlight hours. Sunlight 6.33Hrs / Available 6.20 Hrs

Calculate amount of solar needed to meet Electrical needs:

1: Average solar per Month: 44,863 KHW/12 =3,738.6 KWH/Mth
2. Average solar per day 3,738.6Kwh/30 = 124.612 KWH
3: Amount solar per hour: 124.612 / KWH/6.20hrs*1000watts/1KWH= 20,099 Watts/Hr
4. Inverter efficiency: (20,099 watts/hr)/.96 = 20,936 Watts/Hr
5: # of Sharp 235W panels: 20,936W/235W= 89.089 or 90 panels
6. # Inverters: 3 Sunny Boy 7000US (240V) Inverters
7.  System Size 21.15 KW
8. Actual Size:  15.51 kW

Most grid-connected solar energy systems work the same way:

1. Solar Energy is converted to electricity via photo-voltaic modules
2. An inverter converts the DC (think battery) electricity into AC (what our home use)
3. Some sort of cut-off switch or breaker is used to isolate the system from the grid
4. Your meter measures the solar energy created by your PV array.