January 5, 2016

In the solar industry, we often hear about the benefits of solar for building and property owners. But as we enter what is expected to be the solar industry’s biggest year ever, it’s a good time to talk about the actual process of solar installations, specifically how long it takes from “Yes, I’m interested!” to flipping on the switch and generating renewable solar energy.

If going solar is something you are thinking about doing in the next year, you need to start the process sooner than you think. Here’s why: solar arrays need to go through four major phases in order to be “turned on,” and those steps can sometimes take longer than anticipated. A big part of one of those steps—interconnection—is literally out of your hands.

Let’s quickly look at the steps, and the time they generally take:

Solar Timeline-Blog-Image


  • Assessment/Prescreen (~10 days). An initial site assessment can be done in a single day but the utility prescreening, which provides up-front visibility to available solar capacity for the site, takes at least 10 business days.
  • Design/Engineering & Utility Interconnection Application (6-8 weeks). This process includes structural engineering, solar design, electrical design, and an interconnect application that is submitted to the utility. The majority of time in this step is the interconnection application (IA), which can take up to 60 days (or sometimes longer for larger projects) to complete. Systems larger than 500 kW could be subject to an impact study by the utility, which requires additional time and costs.
  • Procurement and Construction (~6-8 weeks). This process includes contract signing, equipment ordering, permitting, equipment delivery planning, site safety preparation, equipment installation, electrical installation, inspection and testing.
  • Utility Commissioning (~2-4 weeks). This process includes electrical inspector sign-off, certificate of completion, site inspection and clean-up, statement of qualification to receive Solar Renewable Energy Certificates (SREC), witness test and final commissioning.

As you can see, the solar timeline can be a lengthy process from assessment to commissioning, and the longest part can be waiting for the interconnection application to receive approval from the utility!

If there ever was a time to get started, it’s now. With the momentum the solar industry is currently experiencing, more and more projects are seeking this request to connect from the utilities- who are not always eager to speed the process along.  Once you make the decision to go solar, you don’t want to wait for weeks on something that is out of your – or our – control. An experienced solar project developer understands the end-to-end process and can help ensure your project moves through each step in an appropriate timeframe. Do yourself a favor, and keep timeline in mind when considering a solar installation.