Case Study – Home Solar Panel Installation Leads to 115% Savings!


Project Summary

The Brown family bought a brand new home in late 2010. After living in the home with their 2 young children for a year, the Brown’s recognized they had a large south-facing roof, the preferred orientation for a solar panel installation, and were curious to hear about cost and tax credits for a solar home upgrade. They were able to research online and then set up an appointment with a Solar Energy USA Energy Consultant who analyzed their power bill data and recommended a system based on individual need.


Normally a combination of energy reduction + energy production is needed to eliminate a power bill. However, the Brown family’s power bills were lower than national averages, so one main challenge was which home energy solution(s) to recommend. Another challenge was what size solar panel system to recommend in order to maximize available tax credits. One final challenge was suggesting a solar panel and solar array design that would blend seamlessly into the dark asphalt shingle roof.


After analyzing the Brown’s power bills and talking about different home energy improvement packages, a 22 panel solar array was determined to be the best solution to both maximize solar tax credits and cover a majority of energy costs. A 5.17kW solar array was designed using 22 235 watt Sharp solar panels with black frames, installed in 2 rows of 11 for a clean and symmetric look. The panels were positioned on the roof so that 1 final row of 11 solar panels could be added at a later date should the home owners desire to expand their home solar panel system.


The photovoltaic home solar panel array was installed in October of 2011. The system was designed to offset approximately 77% of the annual home power bill with an average savings of around $200 dollars per month over the 40 year expected life of the system. In November of 2011 the Browns paid for just 106 kWh, and in many months since they have received a credit on excess power production including an $8 dollar credit on their May 2012 power bill. The Brown’s were able to take advantage of a 30% federal tax credit, a 35% state of Georgia tax credit, and an extra utility rebate from local power provider Sawnee EMC which covered another $1,500 dollars!

Home Solar Panel Installation Specifics

22 235W Sharp Solar Panels
Enphase M215 Microinverters
5.17kW Total Solar Array
Net Zero Home
To see a video of this 22 panel installation visit
April 2011 – 2012 Power Bills
Above: Panels were installed in October 2011. Note the dramatic decline beginning in September 2011. This bill also shows the home owners were credited for 117 kWh in April 2012 compared to being billed for 743 kWh in April 2011, a 115% reduction!
September 2011 – 2012 Power Bills
Above: This bill shows 1 year worth of power usage following solar panel installation October 2011. Note that in September 2012 406 kWh were used compared to 1,441 kWh in September 2011, a 71% reduction.
April 2012 – 2013 Power Bills
Above: The Detailed Energy Usage table on the right shows that in 5 months out of the past 12 there was an excess solar energy production credit given to the home owners thanks to the rooftop solar panel system. In August of 2012, the hottest month of the year, the home owners used just 615 kWh compared to 1,405 kWh in August of 2011 (before solar), a 56% reduction.