Solar “Farm” and the Airport

Our local utility, OPALCO, is seeking comments on a proposed Solar Array site where Douglas Road turns westward into Bailer Hill Road. Past President and CFI Dan Schwartz sent out a message - using the older “discussions@SJPA” group email - about possible impacts of this array on operations in the pattern of KFHR. A number of you have responded with good comments across the spectrum of supporting or opposed to the proposed solar panel site. Unfortunately, several of these comments came addressed only to Dan’s email address or even as texts to his telephone. Several responses included results of studies on the issue and FAA documents…all of which are worth sharing with our membership and other interested parties. So, we are going to migrate the discussion to this venue since Dan doesn’t have the time or bandwidth to curate and re-post multiple comments via the SJPA email. That’s what this site is for! We will get a group email out to re-direct the discussion here. Thanks for your interest and concerns.

For those of you that missed it, here is my original message:

The proposed solar panel farm is problematic for several reasons, but as a pilot I have an additional concern: this array location will be directly under the entry for the right downwind leg of the Friday Harbor Airport traffic pattern for runway 16 (during south operations) — and it sits slightly to the right of the extended straight out takeoff direction for aircraft departures on runway 16. Solar panel arrays project blinding glare on bright sunny days, largely unnoticed by people on the ground, but a well known hazard to aircraft maneuvering at low altitude nearby, as they arrive at, or depart from, our busy airport. The proposed location is a poor choice, with potential safety implications for aviation operations. Please join in letting OPALCO know about this issue and our concerns.

Thank you,


Capt. Daniel Schwartz, USMM Ret.


Member and Past President,

San Juan Pilots Association

One of our pilots, who is also an experienced architect for major civic engineering and infrastructure projects wrote:

This issue has been discussed many times. It’s interesting to not see the concerns that were raised earlier. Oh well….

Solar farms are possible sources of objectionable glare. The FAA has many studies on this. The company I worked with (twenty+ years ago – getting older :frowning:) did one of the first studies for the FAA. I believe Todd has this information.

I-84 in Pendleton has this glare issue. Google I-84 Pendelton solar glare problem. They now have a warning sign on the freeway alerting drivers to glare. The problem is real if not carefully considered.

In my opinion, a solar farm is OK if……

  1. Solar panels placed such that they produce no objectionable glare. Interesting that new studies on PV panel efficiency suggest panels placed vertically aligned in NS rows are most efficient. What I like about this is no upward glare is possible and better PV performance is achieved at the latitude that is FHR. This is not the ‘common’ installation of placing solar panels at right angles to noon sun. The combination of early and late sun on vertical panels promotes longer solar exposure and a more even output. Anyway……it’s important that current thinking be used and not the status quo of a few years ago as this might preclude aircraft safety concerns. Dare I say win-win?
  2. Any proposal must be carefully vetted by modeling reflection done by and with credible engineering.

Solar panels are, by design, non-reflective. The problem is two-fold. (1) Solar panel grids and frames are often clear anodized aluminum which, with a large field of panels, can produce significant objectionable reflective glare. It may be that black anodized frames with ‘all black’ panels help eliminate this concern. (2) the big concern is surface glare, or sheen, from the glass surface of the panel. This second item is big – the gorilla in the China shop – the I-84 reality. Surface sheen, or glare, is the bad in the good, bad, and ugly nature of a solar farm.

Another member who has extensive flying time in the sunny Southwest sent the following observations:

I’ve got to put forth an “on the other hand” note here. Otherwise stated, I respectfully disagree. Over the last ten years, I have flown extensively over Nevada, Utah, and Arizona. The desert southwest has several massive solar farms that I have flown over. I have never noticed any blinding glare from any of these solar farms. By contrast, the San Juan Island solar farm is tiny by comparison. I can imagine a circumstance where at the perfect time of day, there might be a glare. But it would only be momentary. Also the critical phases of the pattern for rwy 16, base to final and final, would be a long way from the Bailor Hill project. As a Friday Harbor pilot, this solar farm doesn’t worry me too much.

Another member notes the minimal effect at cruising altitudes that might be different at pattern-altitude:

Thanks Dan, I have frequently flown over a large solar array about 15 miles to the west of the SUA airport here in Florida, attached is a photo of that in full reflection mode. Not so bad from higher altitude in the CJ2, but not so good in a low altitude pattern.

Here is an FAA document on the subject:

I just registered for tomorrow’s OPALCO Zoom at 4:00 PM. We’ll see how many of us are permitted to give input. I am going to try to speak to the inputs shared by our island aviation interests - regarding operations in the San Juan Airport traffic pattern. The link below takes you to the page where you need to register for the Zoom meeting.



I missed the meeting. How’d it go?