Installing Solar Panels on your House

In 2017, we decided to add roof-top solar panels to our house to supplement our years-long subscription to Xcel's Windsource program. We had 17 solar panels (system size 4.93 kw) installed on our roof in June of 2017 for $14,889.  Here is the process we followed:

1. Understand electricity usage from Xcel reports. You can create a free online account with Xcel and download reports on your usage. This is interesting in itself, and you should be doing everything you can to reduce your usage, including LED lights. Our 12- month usage as of Jan 2016 was 12,818 kWh, or a 17,150 lb carbon footprint. While we could have installed more panels than the 17 we elected to do, we'd decided that we wanted to spend about $15K on this project, so that limited the number of panels we would buy.

2. Learn about any rebates you can qualify for. We qualified for both Solar Rewards through Xcel ($0.08/kWh paid for our production for 10 years), and for a first-year 30% federal tax write-off on a portion of the cost of the panels. The tax write-off essentially decreased the cost of the panels to $10.4 K. Our expected payback was about 10-12 years or so.

3. Assess your roof. Our roof was about 18 years old, and given the life of panels (up to 25 years), you want to install them on a newer roof, or else there is an expense to having the panels removed and reinstalled with future roofing jobs. We elected to install a new roof, including converting from a number of roof vent boxes to a single ridge-line roof vent to allow uninterrupted roof area to place the panels.

4. Obtain bids and select your solar installer. We obtained bids from three different solar installers:

• Innovative Power Systems
• All Energy
• Applied Energy Innovation

We went with Innovative Power Systems. It's pretty common that the panels they quote you won't be the same ones they install, since panel models, like computers, are frequently changing, so we had a small reduction in price when they ordered our panels. The installation was easy, and only took a few days. We have a monitoring system that we can easily check with our computer, and that can generate easy production reports for us:

Report on solar production by month and year

Our per-panel production reporting- the panels on the left are more shaded by trees than on the right

In 2018, our panels produced 3,722 kWh of the 9,416 we used, or about 40% of our usage and we earned a Solar Rewards rebate of $298, in addition to the much lower electricity bills through the year. We have remained on WindSource for the energy we purchase.

Solar Panels Installed

2020 Addendum: The current percentage of US homes with solar panels is estimated at 1.5% but is expected to grow to 2.5% by 2024. In reviewing our production and expense numbers through year-end 2020, we're on track for full payback in the anticipated 10-12 years.