NOTE: See UPDATE at the bottom of this post.
Southwest Florida is starting to see all Lamar Advertising’s Billboards getting solar panel upgrades. My frustration level with this project is quite high already, first because I believe it was ill-conceived greenwashing, but also because it was poorly implemented. Here is a picture of a billboard in Fort Myers (which thankfully does not host Fafco Solar’s advertisement). Can you spot anything wrong?
Lamar Advertising Solar Billboard in Fort Myers on US41
Lamar used cookie-cutter prefabricated steel racks on their billboards. It would have been far more efficient to install all of these 12 solar panels on a single rack system, purpose-built for the billboard. But that is not the main problem here.
This system was installed by an electrician, whose name I will not mention. Electricians are authorized by Florida Statute to install solar electric systems. That does not make them experts, and here is a prime example. Still looking for the reason that this was done wrong?
A rack mounted solar array at optimal tilt and orientation has all solar panels facing the same direction.
There is only one ideal tilt angle and compass orientation for grid-connected solar photovoltaic systems in Southwest Florida. This tilt angle and orientation will harness the maximum amount of solar energy over the course of a year. Unless there are other cost, aesthetic, or technical reasons for an alternate orientation, solar panels should always be installed in manner that maximizes solar output. All six of the solar arrays are installed with different tilt angles and different compass directions. Although they are generally pointing south, and at a reasonable tilt angle, there is no physical constraint that would cause someone to design the system this way. Plus, it looks terrible.
The optimum tilt and orientation for solar modules can be found using publicly available resources that use a long history of local weather and solar radiation. It’s no secret where to find this information. The National Renewable Energy Labs is the preeminent source used in the U.S. to help solar installers maximize performance under given circumstances.
I would love to give Lamar and the installer the benefit of the doubt, thinking that this would be a test system to see what orientation works out best. After all, each of the six arrays features it’s own microinverter (the now obsolete Enphase D380). It would be easy to monitor each array to determine which produces the most energy over time. However, I can’t imagine this was the intention. I believe it is just a sloppy installation, bordering on complete incompetence.
The lesson: hire a solar professional, preferably someone local.
UPDATE February 29, 2012:
I have been having a lively discussion with Lamar’s Director of Sustainability and Product Research both in the comments below and by email. I am happy to report that the solar panels were askew in the picture above at the time of an upgrade to a digital billboard. It certainly makes sense that more solar capacity is present on this billboard than others, as the electrical draw will by significantly greater. I’m not sure how “sustainable” it is to use an electronic billboard, but it does look great and at least it is powered in part by solar energy.
It’s clear to me now that Lamar does take this project very seriously. After all, just having a Director of Sustainability shows significant commitment. We have a legitimate and passionate disagreement about how the money was spent on this project, and that’s fine with me. My position is borne out of financial reason. His position is that I am being short-sighted.
To be clear, I acknowledge that Lamar is vigorously and sincerely trying to encourage people to use solar energy, and that they are dedicated to a prominent sustainability program. I also appreciate the Director of Sustainability’s passion in defending the program.
There’s no perfect way to spend money to encourage people to “go solar.” Case in point is FPL’s $15.5M per year funding of its solar rebate program. Of this money, $5.6M was allocated to residential solar electric projects in the first round of financing for 2011, resulting in 2.8 megawatts of solar electric capacity (estimated based on the $2/w rebate amount). That’s a much better bang-for-the-buck than Lamar got with it’s spending to encourage solar energy. By the way – the funds for the rebate were exhausted in about 15 minutes after the rebate windows was opened. But, there have been negative consequences of the program. Primarily, the funding strategy limits the number of ”lucky winners” in a very short window and discourages adoption of solar energy by those that cannot access a rebate because of the perception that solar energy needs rebates to be viable.
I have to ask – how much solar capacity has been installed in Florida as a result of the $2.5M of Federal grant money and $10.0M investment made by Lamar? Unfortunately, unlike the FPL rebate program, Lamar’s advertising campaign does not have people banging down the doors of solar dealers in Florida. I should probably be saying “thank you” for the free advertising, but I still contend that it’s solar done wrong.