Review for Cosmo Solaris

01/15/2026
Osprey Oakton, VA

In late October, after a delay beyond my control, I obtained 3 bids for a solar system in an attempt to meet the Dec 31 tax credit deadline. I'm an engineer with professional registration in 11 states, and have led many major projects around the world; I did not really believe it could be done. Sierra, the lead contact with CosmoSolaris, provided the most complete bid with high-quality equipment at a reasonable cost. Sierra was very pleasant to work with, and extremely prompt in replying to my requests and possible options. She was very knowledgeable and cognizant of the need for an efficient time schedule. She scheduled the site inspector for the next day, a Saturday. After a couple of discussions regarding less than optimum roof angles and winter tree shading with Martin, the lead designer and Project Manager, the revised model design was completed. I agreed with Sierra on the Final Agreement (she gave, and kept her word on a key final term that I was concerned with), and the install race was on. Cosmo submitted the final designs and obtained County permit approval extremely quickly (from experience, I know that is not always easy), and scheduled installation. I quickly replaced the marginal roof section, and their team installed the entire system on one mid December day, dodging snow and freezing temperatures elsewhere in the East. I can just imagine the challenges the Cosmo teams had with numerous system installs in progress simultaneously, all with the same deadline, the two major holidays, and the lousy polar vortex weather occurring across the country. The final County electrical inspection took literally one minute, since the high-quality install was evident, and the County's "Final Passed" document and the verification from Martin were both in my inbox in less than a half hour. The deadline was easily met! A couple days later (not the anticipated month), the utility granted approval to activate the system. I threw the switch on the morning of Dec 31! It has been interesting and exciting watching the blue graph of the Enphase app showing power generation, even on cloudy days! I don't know all the players on the Cosmo team, but the behind the scenes organization and efficiency was obvious, as the County, Utility, Enphase software, PJM, GATS, accounting, and tax form paperwork and approvals seem to just appear in my inbox - almost completely filled out with minimal for me to do. There are only a couple remaining minor tasks to complete. I am very happy to have become my own little home power plant, with top-of-the-line panels and microinverters, all designed and installed in record time. CosmoSolaris was up for the challenge and met the tax deadline. Thank you all !